1
|
Jiang T, Li X, Yang J, Wang L, Wang W, Zhang L, Wang B. Potential of free nitrous acid (FNA) for sludge treatment and resource recovery from waste activated sludge: A review. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 360:121170. [PMID: 38749134 DOI: 10.1016/j.jenvman.2024.121170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 04/18/2024] [Accepted: 05/11/2024] [Indexed: 06/05/2024]
Abstract
The escalating production of waste activated sludge (WAS) presents significant challenges to wastewater treatment plants (WWTPs). Free nitrous acid (FNA), known for its biocidal effect, has gained a growing focus on sludge dewatering, sludge reduction, and resource recovery from WAS due to its eco-friendly and cost-effective properties. Nevertheless, there have been no attempts made to systematically summarize or critically analyze the application of FNA in enhancing treatment and resource utilization of sludge. In this paper, we provided an overview of the current understanding regarding the application potential and influencing factors of FNA in sludge treatment, with a specific focus on enhancing sludge dewatering efficiency and reducing volume. To foster resource development from sludge, various techniques based on FNA have recently been proposed, which were comprehensively reviewed with the corresponding mechanisms meticulously discussed. The results showed that the chemical oxidation and interaction with microorganisms of FNA played the core role in improving resource utilization. Furthermore, current challenges and future prospects of the FNA-based applications were outlined. It is expected that this review can refine the theoretical framework of FNA-based processes, providing a theoretical foundation and technical guidance for the large-scale demonstration of FNA.
Collapse
Affiliation(s)
- Tan Jiang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Xiaodi Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Jiayi Yang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Lu Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Wen Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Li Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Bo Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
| |
Collapse
|
2
|
Proano CA, Liu R, Xu X, Meisler S, Hassanein A, Lansing S, Tian K, Li G. Impacts of free nitrous acid on stabilizing food waste and sewage sludge for anaerobic digestion. BIORESOURCE TECHNOLOGY 2024; 402:130819. [PMID: 38723728 DOI: 10.1016/j.biortech.2024.130819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 04/29/2024] [Accepted: 05/07/2024] [Indexed: 05/12/2024]
Abstract
This work investigated the effectiveness of free nitrous acid (FNA) in enhancing organic waste solubilization to improve biogas production in anaerobic digestion (AD). The results indicated that FNA pretreatment can enhance soluble organic content and control H2S odor in tested organic wastes, including food waste, sewage sludge, and their combination. However, a significant decrease (>50 %) in FNA concentration was found in the reactors, possibly due to denitrifier-driven NO2- consumption. Biochemical methane potential (BMP) tests showed a 25 ± 8 % enhancement in CH4 production in the reactors fed with mixed substrate pretreated with 2.9 mg FNA-N/L. However, the presence of NO2- (325.6-2368.0 mg N/L) in some BMP reactors, due to carryover from FNA pretreatment, adversely affected CH4 production (>55 %) and prolonged lag time (>4.2 times). These findings are valuable for researchers and practitioners in waste management, offering insights for implementing FNA pretreatment to enhance the biodegradability of organic wastes in AD.
Collapse
Affiliation(s)
- Camila A Proano
- Department of Civil and Environmental Engineering, University of Maryland, 4298 Campus Dr., College Park, MD 20742, USA
| | - Ruizhe Liu
- Department of Civil and Environmental Engineering, University of Maryland, 4298 Campus Dr., College Park, MD 20742, USA
| | - Xueming Xu
- Department of Civil and Environmental Engineering, Virginia Polytechnic Institute and State University, 200 Patton Hall, Blacksburg, VA 24061, USA
| | - Seth Meisler
- Department of Civil and Environmental Engineering, University of Maryland, 4298 Campus Dr., College Park, MD 20742, USA
| | - Amro Hassanein
- Department of Environmental Science & Technology, University of Maryland, 1429 Animal Sciences/Ag. Eng. Bldg, College Park, MD 20742, USA
| | - Stephanie Lansing
- Department of Environmental Science & Technology, University of Maryland, 1429 Animal Sciences/Ag. Eng. Bldg, College Park, MD 20742, USA
| | - Kuo Tian
- Department of Civil, Environmental, and Infrastructure Engineering, George Mason University, 4400 University Drive, Fairfax, VA 22030, USA
| | - Guangbin Li
- Department of Civil and Environmental Engineering, University of Maryland, 4298 Campus Dr., College Park, MD 20742, USA.
| |
Collapse
|
3
|
Zhou P, Li D, Zhang C, Ping Q, Wang L, Li Y. Comparison of different sewage sludge pretreatment technologies for improving sludge solubilization and anaerobic digestion efficiency: A comprehensive review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 921:171175. [PMID: 38402967 DOI: 10.1016/j.scitotenv.2024.171175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 02/20/2024] [Accepted: 02/20/2024] [Indexed: 02/27/2024]
Abstract
Anaerobic digestion (AD) of sewage sludge reduces organic solids and produces methane, but the complex nature of sludge, especially the difficulty in solubilization, limits AD efficiency. Pretreatments, by destroying sludge structure and promoting disintegration and hydrolysis, are valuable strategies to enhance AD performance. There is a plethora of reviews on sludge pretreatments, however, quantitative comparisons from multiple perspectives across different pretreatments remain scarce. This review categorized various pretreatments into three groups: Physical (ultrasonic, microwave, thermal hydrolysis, electric decomposition, and high pressure homogenization), chemical (acid, alkali, Fenton, calcium peroxide, and ozone), and biological (microaeration, exogenous bacteria, and exogenous hydrolase) pretreatments. The optimal conditions of various pretreatments and their impacts on enhancing AD efficiency were summarized; the effects of different pretreatments on microbial community in the AD system were comprehensively compared. The quantitative comparison based on dissolution degree of COD (DDCOD) indicted that the sludge solubilization performance is in the order of physical, chemical, and biological pretreatments, although with each below 40 % DDCOD. Biological pretreatment, particularly microaeration and exogenous bacteria, excel in AD enhancement. Pretreatments alter microbial ecology, favoring Firmicutes and Methanosaeta (acetotrophic methanogens) over Proteobacteria and Methanobacterium (hydrogenotrophic methanogens). Most pretreatments have unfavorable energy and economic outcomes, with electric decomposition and microaeration being exceptions. On the basis of the overview of the above pretreatments, a full energy and economy assessment for sewage sludge treatment was suggested. Finally, challenges associated with sludge pretreatments and AD were analyzed, and future research directions were proposed. This review may broaden comprehension of sludge pretreatments and AD, and provide an objective basis for the selection of sludge pretreatment technologies.
Collapse
Affiliation(s)
- Pan Zhou
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Dunjie Li
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Cong Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Qian Ping
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Lin Wang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Yongmei Li
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
| |
Collapse
|
4
|
Okoye F, Kakar FL, Elbeshbishy E. Novel free nitrous acid and ultrasonication pretreatment enhanced sludge biodegradability. ENVIRONMENTAL TECHNOLOGY 2024; 45:1829-1840. [PMID: 36469644 DOI: 10.1080/09593330.2022.2155252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
The main goal of this study was to investigate the novel combined Ultrasonication and Free Nitrous Acid (FNA) pretreatment on biodegradability and kinetics of thickened waste-activated sludge (TWAS). Partial factorial design with four levels of (0, 600, 1500, and 3000 KJ/Kg) for ultrasonication and 0, 0.7, 1.4, and 2.8 mg HNO2-N/L for FNA dose were examined creating 16 different combinations. Results revealed that combined pretreatment could significantly improve solubilization and solid destruction compared to solo pretreatments. The highest organic matter solubilization of 25.6% and volatile suspended solids destruction of 21.7% were observed when 2.8 mg HNO2-N/L and 1500 KJ/Kg were combined. Moreover, combining the pretreatments further enhanced biodegradability up to the highest percentage of 50.3% when pretreatment of 3000 KJ/Kg and 2.8 mg HNO2-N/L was applied. Also, the experimental data from a biochemical methane potential test was fitted well into First Order Kinetic and Modified Gompertz models, given that the coefficients of determination, R2, for models at all treatment levels were above 99%.
Collapse
Affiliation(s)
- Frances Okoye
- Environmental Research Group for Resource Recovery, Department of Civil Engineering, Faculty of Engineering, Architecture and Science, Ryerson University, Toronto, Canada
| | - Farokh Laqa Kakar
- Environmental Research Group for Resource Recovery, Department of Civil Engineering, Faculty of Engineering, Architecture and Science, Ryerson University, Toronto, Canada
| | - Elsayed Elbeshbishy
- Environmental Research Group for Resource Recovery, Department of Civil Engineering, Faculty of Engineering, Architecture and Science, Ryerson University, Toronto, Canada
| |
Collapse
|
5
|
A new ultrasound-assisted liquid-liquid microextraction method utilizing a switchable hydrophilicity solvent for spectrophotometric determination of nitrite in food samples. J Food Compost Anal 2023. [DOI: 10.1016/j.jfca.2023.105267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2023]
|
6
|
Wang C, Wang Y, Chen Z, Wei W, Chen X, Mannina G, Ni BJ. A novel strategy for efficiently transforming waste activated sludge into medium-chain fatty acid using free nitrous acid. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 862:160826. [PMID: 36502988 DOI: 10.1016/j.scitotenv.2022.160826] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 11/30/2022] [Accepted: 12/06/2022] [Indexed: 06/17/2023]
Abstract
The global energy crisis is approaching due to rapid population growth and overexploitation of fossil fuels. Therefore, the development and use of new and renewable energy sources is already in the extreme urgency. This work developed a novel technology to efficiently produce renewable liquid bioenergy from discarded wastes, by effectively transforming sewage sludge into high-value medium chain fatty acids (MCFA). The maximum MCFA yield in the anaerobic sludge fermentation was revealed to be 10.6 times of control when utilizing sewage sludge with 1.78 mg-N/L free nitrous acid (FNA) pretreatment. The carbon flow from sewage sludge into MCFA in the fermentation system was significantly enhanced with appropriate levels (0.71-1.78 mg-N/L) of FNA pretreatment. Compared to FNA pretreatment, however, its direct addition severely inhibited total products (i.e., carboxylates and complex alcohols) generation because of the toxicity on live cells (decreasing to 8.3 %-13.9 %) in sludge. Kinetic models (one-substrate and two-substrate) were utilized to investigate the mechanism of MCFA promotion by FNA pretreatment on anaerobic sludge fermentation, in which linear relationship analysis between FNA-derived organic release and the fitted parameters were also performed. The results indicated that the conversion of refractory materials into rapidly bioavailable substrates for MCFA production contributed to increasing MCFA production rate and potential. Moreover, the relative abundances of functional microorganisms related to hydrolysis-acidification and chain elongation process increased under FNA pretreatment, further favoring the MCFA production. This study provides a novel and effective technology of sludge energy recovery that can achieve the next-generation sustainable sewage sludge management.
Collapse
Affiliation(s)
- Chen Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Yun Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Zhijie Chen
- School of Civil and Environmental Engineering, Centre for Technology in Water and Wastewater, University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Wei Wei
- School of Civil and Environmental Engineering, Centre for Technology in Water and Wastewater, University of Technology Sydney, Sydney, NSW 2007, Australia.
| | - Xueming Chen
- Fujian Provincial Engineering Research Center of Rural Waste Recycling Technology, College of Environment and Safety Engineering, Fuzhou University, Fujian 350116, China
| | - Giorgio Mannina
- Engineering Department, Palermo University, Ed. 8 Viale delle Scienze, 90128 Palermo, Italy
| | - Bing-Jie Ni
- School of Civil and Environmental Engineering, Centre for Technology in Water and Wastewater, University of Technology Sydney, Sydney, NSW 2007, Australia
| |
Collapse
|
7
|
Li X, Wang B, Ma Y, Jiang T, Peng Y. Enhanced mesophilic fermentation of waste activated sludge by integration with in-situ nitrate reduction. BIORESOURCE TECHNOLOGY 2023; 368:128317. [PMID: 36375702 DOI: 10.1016/j.biortech.2022.128317] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 11/07/2022] [Accepted: 11/08/2022] [Indexed: 06/16/2023]
Abstract
This study investigated the reduction of nitrate in a mesophilic waste activated sludge (WAS) fermentation system and determined the effect of nitrate reduction on the hydrolysis, acidogenesis and acetogenesis. Experimental results showed that the initial nitrate concentrations of 100, 200 and 400 mg/L were completely reduced in 1, 2 and 7 days, respectively. The destruction of volatile suspended solids was 1.2, 1.8 and 2.8 times, respectively, that without nitrate, demonstrating nitrate promoted the release of organic matter in sludge and enhanced the biodegradability of sludge organics. Moreover, batch tests using model substrates illustrated nitrate reduction promoted sludge hydrolysis and acetogenesis, but slightly inhibited acidogenesis. This study offers a feasible method to address two major problems currently faced by biological wastewater treatment plants, i.e. the overabundance of WAS and the lack of carbon sources for the denitrification process.
Collapse
Affiliation(s)
- Xiaodi Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Bo Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
| | - Yuqing Ma
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Tan Jiang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| |
Collapse
|
8
|
Kakar FL, Liss SN, Elbeshbishy E. Differential impact of acidic and alkaline conditions on hydrothermal pretreatment, fermentation and anaerobic digestion of sludge. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2022; 86:3077-3092. [PMID: 36579871 DOI: 10.2166/wst.2022.368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Anaerobic digestion and fermentation processes in wastewater sludge treatment are limited by several factors, including the slow breakdown of complex organic matter and solubilization of solids. In this study, thermochemical pretreatment of thickened waste activated sludge using high temperature (>170 °C) was investigated to understand the impact of the pretreatment on the volatile fatty acids (VFA) production and its fractions during the fermentation process. Furthermore, the influence the thermochemical pretreatment on sludge disintegration and methane recovery was investigated. A range of acidic and alkaline conditions over the pH range of 4.5-10 was examined. Sludge (pH adjusted) was exposed to hydrothermal pretreatment (HTP) at a temperature of 170 °C for 30 min. Pretreated samples were then subjected to batch fermentation and methane potential tests which revealed that acidic and alkaline conditions resulted in increased sludge solubilization during HTP. Acidic conditions were associated with a higher VFA production yield of up to 185 mg chemical oxygen demand/g total chemical oxygen demand. Alkaline conditions led to a higher methane production yield where the maximum yield (276 mL CH4/g total chemical oxygen demandadded) was found to occur at pH 10. Therefore, alkaline sludge used for fermentation has shown technical and economic feasibility for sludge carbon recovery.
Collapse
Affiliation(s)
- Farokh Laqa Kakar
- Environmental Research Group for Resource Recovery, Department of Civil Engineering, Faculty of Engineering, Architecture and Science, Toronto Metropolitan University (formerly Ryerson University), 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada E-mail:
| | - Steven N Liss
- Department of Chemistry and Biology, Faculty of Science, Toronto Metropolitan University (formerly Ryerson University), 350 Victoria Street, Toronto, Ontario M5B 2K3, Canada; Department of Microbiology, Stellenbosch University, Private Bag, XI, Matieland 7602, Stellenbosch, South Africa
| | - Elsayed Elbeshbishy
- Environmental Research Group for Resource Recovery, Department of Civil Engineering, Faculty of Engineering, Architecture and Science, Toronto Metropolitan University (formerly Ryerson University), 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada E-mail:
| |
Collapse
|
9
|
Meng J, Duan H, Yuan Z, Zheng M. Gravity settling and centrifugation increase the acid buffer capacity of activated sludge. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 820:153231. [PMID: 35065124 DOI: 10.1016/j.scitotenv.2022.153231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 01/13/2022] [Accepted: 01/13/2022] [Indexed: 06/14/2023]
Abstract
Buffer capacity is a critical parameter in sludge management of domestic wastewater treatment plants that determines acid/base usage. It is here shown that gravity settling or centrifugation significantly increased the buffer capacity in the supernatant of the sludge. The sludge thickening considerably elevated the total alkalinity of the sludge from 16.0 to 31.5 mgCaCO3 taking pH 5.0 for example with the sludge concentration times increasing from 2 to 20 times, while insignificantly affected the total acidity (initial 335.3 vs 240.2 mgCaCO3 at concentration times of 10 considering pH increased to 11.0). These findings indicate that the inherent buffer in sludge can be released during sludge thickening and the primary component of this buffer is alkalinity. The released buffer may be correlated to a negative surface charge inside sludge flocs, as it consumed base in titration. The increased buffer capacity in supernatant could be due to the buffer released from bound water to free water, and in particular, from the release of interstitial water, an important part of the bound water. Further mechanism analysis suggested that the increased buffer capacity in thickened sludge could relate to extracellular polymeric substances, for which more studies are needed. Overall, this study for the first time reports that sludge thickening can change the buffer capacity of sludge, affecting the efficiency and acid/base usage of sludge treatment.
Collapse
Affiliation(s)
- Jia Meng
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, Brisbane, QLD 4072, Australia; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China
| | - Haoran Duan
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, Brisbane, QLD 4072, Australia
| | - Zhiguo Yuan
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, Brisbane, QLD 4072, Australia
| | - Min Zheng
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, Brisbane, QLD 4072, Australia.
| |
Collapse
|
10
|
Uthirakrishnan U, Godvin Sharmila V, Merrylin J, Adish Kumar S, Dharmadhas JS, Varjani S, Rajesh Banu J. Current advances and future outlook on pretreatment techniques to enhance biosolids disintegration and anaerobic digestion: A critical review. CHEMOSPHERE 2022; 288:132553. [PMID: 34653493 DOI: 10.1016/j.chemosphere.2021.132553] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 09/27/2021] [Accepted: 10/10/2021] [Indexed: 06/13/2023]
Abstract
Waste activated sludge (biosolids) treatment is intensely a major problem around the globe. Anaerobic treatment is indeed a fundamental and most popular approach to convert organic wastes into bioenergy, which could be used as a carbon-neutral renewable and clean energy thus eradicating pathogens and eliminating odor. Due to the sheer intricate biosolid matrix (such as exopolymeric substances) and rigid cell structure, hydrolysis becomes a rate-limiting phase. Numerous different pretreatment strategies were proposed to hasten this rate-limiting hydrolysis and enhance the productivity of anaerobic digestion. This study discusses an overview of previous scientific advances in pretreatment options for enhancing biogas production. In addition, the limitations addressed along with the effects of inhibitors in biosolids towards biogas production and strategies to overcome discussed. This review elaborated the cost analysis of various pretreatment methods towards the scale-up process. This review abridges the existing research on augmenting AD efficacy by recognizing the associated knowledge gaps and suggesting future research.
Collapse
Affiliation(s)
- Ushani Uthirakrishnan
- Department of Biotechnology, Karpaga Vinayaga College of Engineering and Technology, Chinnakolambakkam, Chengalpattu, 603308, Tamil Nadu, India
| | - V Godvin Sharmila
- Department of Civil Engineering, Rohini College of Engineering and Technology, Kanyakumari, Tamil Nadu, India
| | - J Merrylin
- Department of Food Science and Nutrition, Sarah Tucker College, Tirunelveli, 627002, Tamil Nadu, India
| | - S Adish Kumar
- Department of Civil Engineering, University V.O.C College of Engineering, Anna University Thoothukudi Campus, Tamil Nadu, India
| | - Jeba Sweetly Dharmadhas
- Department of Biotechnology, Karpagam Academy of Higher Education, Coimbatore, 641-021, Tamil Nadu, India
| | - Sunita Varjani
- Gujarat Pollution Control Board, Gandhinagar, Gujarat, 382010, India
| | - J Rajesh Banu
- Department of Life Sciences, Central University of Tamil Nadu, Neelakudi, Thiruvarur, Tamil Nadu, 610005, India.
| |
Collapse
|
11
|
Calderon AG, Duan H, Chen X, Wu Z, Yu W, Silva CE, Li Y, Shrestha S, Wang Z, Keller J, Chen Z, Yuan Z, Hu S. Enhancing anaerobic digestion using free nitrous acid: Identifying the optimal pre-treatment condition in continuous operation. WATER RESEARCH 2021; 205:117694. [PMID: 34607085 DOI: 10.1016/j.watres.2021.117694] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 08/17/2021] [Accepted: 09/20/2021] [Indexed: 05/23/2023]
Abstract
Free Nitrous Acid (FNA) pre-treatment is a promising technology demonstrated effective in improving waste activated sludge degradability and anaerobic digestion (AD) performance. Pre-treatment conditions including FNA concentration and treatment duration determine operational and capital cost of full-scale implementation, which have not been studied in long-term experiments. The knowledge of FNA pre-treatment conditions improving the AD performance is urgently required to determine suitable conditions for the technology implementation. In this work, five different FNA concentrations (2.2, 4.4, 7.2, 12 mgN/L and nitrite only without pH adjustment) and three treatment durations (8, 24 and 48 h) were studied in four lab-scale semi-continuous AD reactors for over 300 days. FNA pre-treatment was shown under all tested conditions effective in enhancing AD performances, while its effectiveness and resulted benefits varied substantially amongst different pre-treatment conditions. The long-term experiment demonstrated that the methane production, sludge reduction and digested sludge viscosity of AD are positively correlated with the FNA concentration and durations, until an optimal condition is reached, which was identified in this work to be FNA concentration of 7.2 mgN/L and treatment duration of 24 h. Microbial community changes supported the apparent observation of enhanced sludge degradation at elevating FNA concentrations applied during pre-treatment. The short-term sludge solubilization results were inconsistent with the long-term AD performance, which was potentially caused by inhibitions from stringent FNA pre-treatment conditions applied (FNA = 12 mgN/L with 24-hour treatment & FNA = 7.2 mgN/L with 48-hour treatment). Overall, results suggested FNA pre-treatment at the optimized condition is highly beneficial to WWTPs and competitive with other pre-treatment technologies, e.g., thermal hydrolysis pre-treatment. This work comprehensively evaluated the key design parameters of FNA pre-treatment process, reached a major milestone in the development and applications of FNA technologies.
Collapse
Affiliation(s)
| | - Haoran Duan
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia; School of Chemical Engineering, The University of Queensland, St Lucia, QLD 4072, Australia.
| | - Xiaoguang Chen
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia; State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China
| | - Ziping Wu
- School of Chemical Engineering, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Wenbo Yu
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia; School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Carlos E Silva
- Federal University of Piaui Campus Ministro Petronio Portela Ininga, Teresina, PI 64049550, Brazil
| | - Yijing Li
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Sohan Shrestha
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Zhiyao Wang
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Jurg Keller
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Zhongwei Chen
- School of Mechanical and Mining Engineering, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Zhiguo Yuan
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Shihu Hu
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia.
| |
Collapse
|
12
|
Jin B, Niu J, Wang L, Zhao J, Li Y, Pang L, Zhang M. Effect of sodium dichloroisocyanurate treatment on enhancing the biodegradability of waste-activated sludge anaerobic fermentation. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 287:112353. [PMID: 33735677 DOI: 10.1016/j.jenvman.2021.112353] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Revised: 02/14/2021] [Accepted: 03/07/2021] [Indexed: 06/12/2023]
Abstract
In the present study, a novel oxidant (sodium dichloroisocyanurate, NaCl2(NCO)3; SDIC) combined with microorganisms was employed to achieve a higher performance of waste-activated sludge (WAS) anaerobic fermentation. Four concentrations of SDIC (0, 0.3, 0.6, and 1.0 mg SDIC/mg SS) were studied in WAS fermentation systems. The results showed that the release of proteins and polysaccharides was enhanced by the addition of SDIC with values of 1002.25 mg COD/L and 680.25 mg COD/L, respectively, and these values increased 14.46-18.07 times (proteins) and 3.74-7.40 times (polysaccharides) compared with that of the blank test. Additionally, the short-chain fatty acids also increased 2.24 times. The rate of extraction of organic substances from the sludge increased from 3.03% to 33.33%. Furthermore, the fermented sludge with the SDIC treatment had higher hydrolytic acidification efficiencies for bovine serum albumin and glucose, increasing from 4.558% to 9.91% and 2.976%-6.764%, respectively. However, SDIC treatment of the conventional fermented sludge resulted in lower hydrolytic acidification efficiencies with values of 4.978%-1.781% and 3.334%-0.582%, respectively. Biological enzyme analysis also showed that SDIC enhanced α-glucosidase and protease activity but inhibited dehydrogenase, alkaline phosphatase, and acid phosphatase activity. Proteobacteria and Comamonas were the main microbial communities observed in the WAS anaerobic fermentation.
Collapse
Affiliation(s)
- Baodan Jin
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, 450001, China.
| | - Jintao Niu
- Henan Hengan Environmental Protection Technology Co., Ltd, Zhengzhou, 450001, China
| | - Lan Wang
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, 450001, China
| | - Jianguo Zhao
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, 450001, China
| | - Yu Li
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, 450001, China
| | - Long Pang
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, 450001, China
| | - Miao Zhang
- Yangzhou University, Yangzhou, 225127, China
| |
Collapse
|
13
|
Lu Y, Xu Y, Chen S, Dong B, Dai X. Effect of nitrite addition on the two-phase anaerobic digestion of waste activated sludge: Optimization of the acidogenic phase and influence mechanisms. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 261:114085. [PMID: 32066063 DOI: 10.1016/j.envpol.2020.114085] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 12/24/2019] [Accepted: 01/27/2020] [Indexed: 06/10/2023]
Abstract
To simultaneously achieve biological denitrification and bio-energy recovery from sludge, the effects of nitrite on the two-phase anaerobic digestion (AD) of waste activated sludge were explored. Herein, effects of nitrite on the acidogenic phase are optimized, and the corresponding influence mechanisms are investigated. The experimental results show that the optimal nitrite treatment conditions for improving the acidogenic phase are an initial pH of 8.0, a nitrite addition concentration of 500 mg NO2--N·L-1, and a fermentation time of six days. By comparing the effects of nitrite and nitrate on the acidogenic phase, it was found that it was the nitrite, not the nitrate, that significantly enhanced the sludge organic solubilization, hydrolysis, and acidification, which are primarily attributed to the redox property of nitrite. Based on an analysis of different forms of soluble nitrogen concentrations, there was no obvious accumulation of nitrite or nitrate during the acidogenic phase. An analysis of the methane production and the volatile solid (VS) degradation during the two-phase AD revealed that the nitrite improved the methane production from the methanogenic phase and enhanced the VS degradation of sludge during the entire two-phase AD process. These findings could provide references for simultaneously treating nitrite-rich wastewater and improving anaerobic sludge digestion via two-phase system.
Collapse
Affiliation(s)
- Yiqing Lu
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; Tongji Architectural Design (Group) Co., Ltd., Shanghai, 200092, China
| | - Ying Xu
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Sisi Chen
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Bin Dong
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China.
| | - Xiaohu Dai
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China
| |
Collapse
|
14
|
Niu C, Zhang Z, Pan Y, Tan Y, Lu X, Zhen G. Does the combined free nitrous acid and electrochemical pretreatment increase methane productivity by provoking sludge solubilization and hydrolysis? BIORESOURCE TECHNOLOGY 2020; 304:123006. [PMID: 32078903 DOI: 10.1016/j.biortech.2020.123006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Revised: 02/02/2020] [Accepted: 02/08/2020] [Indexed: 06/10/2023]
Abstract
Free nitrous acid based pretreatments are novel and effective chemical strategies for enhancing waste activated sludge solubilization. In this study, the synergetic effects of the combined free nitrous acid and electrochemical pretreatment on sludge solubilization and subsequent methane productivity were evaluated. The results indicated that pretreatment with 10 V plus 14.17 mg N/L substantially enhanced sludge solubilization, with the highest soluble chemical oxygen demand concentration of 3296.7 mg/L, 25.6-time higher than that without pretreatment (128.9 mg/L). Due to the potential toxicity of NO2- and NO3- to microorganisms and its bioprocesses, the methane production of sludge pretreated by free nitrous acid was significantly deteriorated. The maximum methane yield (152.0 ± 9.6 mL/g-VSadded) was observed at 10 V pretreatment alone, only 1.7% higher than that of the control (149.4 ± 1.6 mL/g-VSadded). Combined pretreatment indeed enhances the sludge solubilization and hydrolysis, but does not always induce an improved anaerobic digestion efficiency.
Collapse
Affiliation(s)
- Chengxin Niu
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China
| | - Zhongyi Zhang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China
| | - Yang Pan
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China
| | - Yujie Tan
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China
| | - Xueqin Lu
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China; Institute of Eco-Chongming (IEC), 3663 N. Zhongshan Rd., Shanghai 200062, PR China
| | - Guangyin Zhen
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China; Shanghai Institute of Pollution Control and Ecological Security, 1515 North Zhongshan Rd. (No. 2), Shanghai 200092, PR China.
| |
Collapse
|
15
|
Karimi R, Hallaji SM, Siami S, Torabian A, Aminzadeh B, Eshtiaghi N, Zahedi S. Synergy of combined free nitrous acid and Fenton technology in enhancing anaerobic digestion of actual sewage waste activated sludge. Sci Rep 2020; 10:5027. [PMID: 32193461 PMCID: PMC7081239 DOI: 10.1038/s41598-020-62008-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Accepted: 02/12/2020] [Indexed: 11/09/2022] Open
Abstract
In this study, actual swage waste activated sludge in batch reactors was employed to assess the synergistic effect of free nitrous acid and Fenton pre-treatments on enhancing methane production in the anaerobic digestion process. In addition to methane enhancement, the mechanisms driving the enhancement were also investigated via measuring enzymes activity and solubilisation of organic matter. This study revealed that the combined pre-treatments solubilised organic matter significantly more than the bioreactors pre-treated with individual FNA and Fenton. For understanding the influence of pre-treatments on solubilisation of organic matter, soluble protein, soluble polysaccharide and soluble chemical oxygen demand (SCOD) were measured before and after the treatments and it was shown that they respectively increased by 973%, 33% and 353% after the treatments. Protease and cellulase activity, as the key constituents of the microbial community in activated sludge, decreased considerably after the combined pre-treatments 42% and 32% respectively, which resulted in considerable methane enhancement. The results corroborate the synergy of the combined FNA and Fenton pre-treatment in degrading the organic and microbial constituents in waste activated sludge, paving the way for the big-scale implementation of these technologies.
Collapse
Affiliation(s)
- Razieh Karimi
- Gorgan University of Agricultural Sciences & Natural Resources, Golestan, Iran
| | - Seyed Mostafa Hallaji
- Faculty of Engineering, Department of Civil Engineering, Monash University, Melbourne, Australia.
- School of Environment, College of Engineering, University of Tehran, Tehran, Iran.
| | - Salar Siami
- School of Environment, College of Engineering, University of Tehran, Tehran, Iran
| | - Ali Torabian
- School of Environment, College of Engineering, University of Tehran, Tehran, Iran
| | - Behnoush Aminzadeh
- School of Environment, College of Engineering, University of Tehran, Tehran, Iran
| | - Nicky Eshtiaghi
- School of Engineering, Chemical and Environmental Engineering, RMIT University, Melbourne, Australia
| | - Soraya Zahedi
- Catalan Institute for Water Research (ICRA), Girona, Spain
| |
Collapse
|
16
|
Ji J, Peng Y, Wang B, Li X, Zhang Q. Synergistic Partial-Denitrification, Anammox, and in-situ Fermentation (SPDAF) Process for Advanced Nitrogen Removal from Domestic and Nitrate-Containing Wastewater. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:3702-3713. [PMID: 32092267 DOI: 10.1021/acs.est.9b07928] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
This study presents a new method for energy-efficient wastewater treatment that synergizes the partial-denitrification, anammox, and in-situ fermentation (SPDAF) processes in an up-flow reactor. Nitrate-containing wastewater and actual domestic sewage were fed into this SPDAF system, which was operated for 180 days without the addition of external carbon sources and aeration. The total inorganic nitrogen (TIN) removal efficiency reached 93.1% with a low C/N ratio of 1.6, a NO3--N/NH4+-N ratio of 1.13 and a TIN concentration of 92.5 mg N/L. The contribution of anammox to nitrogen removal accounted for 95.6%. Batch tests demonstrated that the partial-denitrification process was able to use organics from either the influent or those produced by fermentation, thus providing nitrite for anammox. Significantly, fermentation played a key role in using the slowly biodegradable organics and provided adequate electron donor for partial-denitrification. Metagenomic sequencing analysis showed that the genera related to partial-denitrification, anammox, and fermentation bacteria were coexisted in this SPDAF system. The key functional genes of anammox bacteria (Hzs, 3986 hits; Hdh, 2804 hits) were highly detected in this study. The abundances of cytoplasmic nitrate reductase (58 706 hits) and periplasmic nitrate reductase (70 540 hits) were much higher than copper nitrite reductase (16 436 hits) and cytochrome cd1 nitrite reductase (14 264 hits), potentially contributing to the occurrence of partial-denitrification. Moreover, different abundances of genes involved in fermentation metabolism suggested that fermentation likely generated easily biodegradable organics for partial-denitrification.
Collapse
Affiliation(s)
- Jiantao Ji
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, P. R. China
- College of Ecology and Environment, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, P. R. China
| | - Bo Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, P. R. China
| | - Xiyao Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, P. R. China
| | - Qiong Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, P. R. China
| |
Collapse
|
17
|
Duan H, Gao S, Li X, Ab Hamid NH, Jiang G, Zheng M, Bai X, Bond PL, Lu X, Chislett MM, Hu S, Ye L, Yuan Z. Improving wastewater management using free nitrous acid (FNA). WATER RESEARCH 2020; 171:115382. [PMID: 31855696 DOI: 10.1016/j.watres.2019.115382] [Citation(s) in RCA: 82] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 12/06/2019] [Accepted: 12/07/2019] [Indexed: 05/06/2023]
Abstract
Free nitrous acid (FNA), the protonated form of nitrite, has historically been an unwanted substance in wastewater systems due to its inhibition on a wide range of microorganisms. However, in recent years, advanced understanding of FNA inhibitory and biocidal effects on microorganisms has led to the development of a series of FNA-based applications that improve wastewater management practices. FNA has been used in sewer systems to control sewer corrosion and odor; in wastewater treatment to achieve carbon and energy efficient nitrogen removal; in sludge management to improve the sludge reduction and energy recovery; in membrane systems to address membrane fouling; and in wastewater algae systems to facilitate algae harvesting. This paper aims to comprehensively and critically review the current status of FNA-based applications in improving wastewater management. The underlying mechanisms of FNA inhibitory and biocidal effects are also reviewed and discussed. Knowledge gaps and current limitations of the FNA-based applications are identified; and perspectives on the development of FNA-based applications are discussed. We conclude that the FNA-based technologies have great potential for enhancing the performance of wastewater systems; however, further development and demonstration at larger scales are still required for their wider applications.
Collapse
Affiliation(s)
- Haoran Duan
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD, 4072, Australia; School of Chemical Engineering, The University of Queensland, St. Lucia, QLD, 4072, Australia
| | - Shuhong Gao
- Institute for Environmental Genomics, Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, 73019, United States
| | - Xuan Li
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Nur Hafizah Ab Hamid
- School of Chemical Engineering, The University of Queensland, St. Lucia, QLD, 4072, Australia
| | - Guangming Jiang
- School of Civil, Mining and Environmental Engineering, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Min Zheng
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Xue Bai
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Philip L Bond
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Xuanyu Lu
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD, 4072, Australia; School of Chemical Engineering, The University of Queensland, St. Lucia, QLD, 4072, Australia
| | - Mariella M Chislett
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Shihu Hu
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Liu Ye
- School of Chemical Engineering, The University of Queensland, St. Lucia, QLD, 4072, Australia
| | - Zhiguo Yuan
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD, 4072, Australia.
| |
Collapse
|
18
|
Zhang F, Peng Y, Li B, Wang Z, Jiang H, Zhang Q. Novel insights into integrated fermentation and nitrogen removal by free nitrous acid (FNA) serving as treatment method. JOURNAL OF HAZARDOUS MATERIALS 2020; 381:120835. [PMID: 31352150 DOI: 10.1016/j.jhazmat.2019.120835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 04/11/2019] [Accepted: 06/26/2019] [Indexed: 06/10/2023]
Abstract
Free nitrous acid (FNA) has only been studied as the pretreatment of waste activated sludge (WAS). Integrated fermentation and nitrogen removal using FNA as a primary means of treatment are seldom investigated. WAS fermentation was characterized under various FNA concentration. The production of COD, protein, and carbohydrate increased with FNA concentration (in the range of 0.197-1.97 mg/L) before the denitrification process. Volatile fatty acids (VFA) were only produced after complete denitrification. Potential FNA impact on fermentation step found FNA facilitated both solubilization and hydrolysis but inhibited acidification, acetogenesis, and methanogenesis processes. The types of fermentation were determined using threedimensional excitation-emission matrix (EEM) fluorescence spectroscopy. Protein-like substances and Tyrosine/Tryptophan were the most dominant dissolved organic matters (DOMs). The cell decay rate increased from 0.044 to 0.102/d based on the nonlinear fitting for the FNA concentration of 0.197-1.97 mg/L. The microbial biomass mortality reached 92.7% when the FNA in tight extracellular polymeric substances (T-EPS) exceeded 0.04 mg/L. In addition, the microbial diversity and microbial structure were substantially reduced by FNA during long-term operation, while the bacterial abundance associated with hydrolysis and acidification increased significantly.
Collapse
Affiliation(s)
- Fangzhai Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
| | - Baikun Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Zhong Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Hao Jiang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Qiong Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| |
Collapse
|
19
|
Wang Y, Wang D, Chen F, Yang Q, Ni BJ, Wang Q, Sun J, Li X, Liu Y. Nitrate addition improves hydrogen production from acidic fermentation of waste activated sludge. CHEMOSPHERE 2019; 235:814-824. [PMID: 31280050 DOI: 10.1016/j.chemosphere.2019.06.117] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 05/24/2019] [Accepted: 06/15/2019] [Indexed: 06/09/2023]
Abstract
In this work, a low-cost alternative method (i.e., adding nitrate into WAS) to significantly enhance hydrogen production was reported. Experimental results showed that with an increase of nitrate addition from 0 to 362 mg/L, the maximal hydrogen production from acidic (pH 5.5) fermentation of WAS obviously increased from 12.6 ± 0.5 to 19.3 ± 0.9 mL per gram volatile suspended solids (VSS). The mechanism investigations illustrated more substrates were provided for subsequent hydrogen production. Although the nitrate added inhibited all the biological processes, its inhibition to the hydrogen consumption processes was much severer than that to the hydrogen production processes. The enzyme analyses on the long-term semi-continuous fermenters showed that the nitrate addition slightly inhibited the relative activities of protease, butyrate kinase, acetate kinase, CoA-transferase, and [FeFe] hydrogenase but largely suppressed the relative activities of coenzyme F420, carbon monoxide dehydrogenase, and adenylyl sulfate reductase.
Collapse
Affiliation(s)
- Yali Wang
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China.
| | - Dongbo Wang
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China.
| | - Fei Chen
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science & Technology of China, Hefei, PR China
| | - Qi Yang
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China
| | - Bing-Jie Ni
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia
| | - Qilin Wang
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia
| | - Jian Sun
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China
| | - Xiaoming Li
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China
| | - Yiwen Liu
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia.
| |
Collapse
|
20
|
Jiang C, Xu S, Wang R, Feng S, Zhou S, Wu S, Zeng X, Wu S, Bai Z, Zhuang G, Zhuang X. Achieving efficient nitrogen removal from real sewage via nitrite pathway in a continuous nitrogen removal process by combining free nitrous acid sludge treatment and DO control. WATER RESEARCH 2019; 161:590-600. [PMID: 31238224 DOI: 10.1016/j.watres.2019.06.040] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 06/15/2019] [Accepted: 06/15/2019] [Indexed: 05/03/2023]
Abstract
The incomplete denitrification due to insufficient carbon resource in the wastewater treatment plants (WWTPs) resulted in low nitrogen removal efficiency, which has become a widespread problem in China and all around the world. Reducing the requirement of carbon source by manipulating the nitrogen removal pathway from conventional nitrification-denitrification to partial nitrification-denitrification is considered as an efficient solution. In this article, the feasibility of combining free nitrous acid (FNA) sludge treatment and DO control to achieve partial nitrification-denitrification in a continuous flow system (aerobic-anoxic-oxic process) using real sewage was assessed. The nitrite pathway was rapidly established in the experimental reactor within 23 days by simultaneously lowering DO concentration in aerobic zone to 0.5 mg/L and treating 30% of the activated sludge per day from the reactor in the FNA sludge treatment unit with FNA concentration of 1.2 mg N/L and exposure time of 18 h. The nitrite oxidizing bacteria (NOB) were efficiently washed out and the partial nitrification process could maintain stable in the experimental reactor even after cease of FNA treatment and increase of DO concentrations in the main stream to 1.5 mg/L, with an average nitrite accumulation rate of above 78%. In contrast, the nitrite accumulation rate was just around 58% during low DO concentrations phase and declined quickly to below 1% after the DO concentrations were increased to 1.5 mg/L in the control reactor which only utilized single strategy of DO control to achieve nitrite pathway. Moreover, a better sludge settleability and nitrogen removal performance could also be realized in the experimental reactor. The results of nitrifying bacteria activities and quantities detection demonstrated that although NOB activities in both reactors were effectively inhibited, a certain amount of NOB (6.26 × 106 copies/g MLSS) were remained in the control reactor and multiplied rapidly as the DO concentration increased, which might break down the partial nitrification. Furthermore, the quantity results of nitrogen cycling related functional genes showed that the increment of the ratio of nitrate reduced bacteria to total bacteria was 0.35% larger than that of nitric oxide bacteria in the control reactor, while those two ratios increased similarly by 1.11% and 1.12% in the experimental reactor, respectively, which might be one potential cause of reduction in N2O emission of nitrite pathway achieved by FNA-based technologies.
Collapse
Affiliation(s)
- Cancan Jiang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Shengjun Xu
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Rui Wang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Shugeng Feng
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Sining Zhou
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Shimin Wu
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiangui Zeng
- Shenzhen DiDa Water Engineering Limited Company, Shenzhen, 518116, China
| | - Shanghua Wu
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhihui Bai
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Guoqiang Zhuang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xuliang Zhuang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China.
| |
Collapse
|
21
|
Wang Z, Wang B, Gong X, Qiao X, Peng Y. Free nitrous acid pretreatment of sludge to achieve nitritation: The effect of sludge concentration. BIORESOURCE TECHNOLOGY 2019; 285:121358. [PMID: 31029041 DOI: 10.1016/j.biortech.2019.121358] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 04/13/2019] [Accepted: 04/16/2019] [Indexed: 06/09/2023]
Abstract
This study investigated the effect of sludge concentration (expressed by mixed liquor volatile suspended solids, MLVSS) on free nitrous acid (FNA) pretreatment strategy to achieve nitritation. Results showed when FNA was 0.308 mgHNO2-N/L, nitrite oxidizing bacteria (NOB) activity increased by 70.2% as MLVSS increased from 8.4 to 16.8 g/L. Nitrite accumulation ceased as MLVSS increased to 12.6 g/L, indicating that FNA inhibition of NOB gradually weakened with increasing MLVSS. When FNA was higher than 0.770 mgHNO2-N/L, NOB activity was completely inhibited and the effect of MLVSS on FNA inhibition was negligible, with nitrite accumulation potential (NAP) varying from 88.1% to 90.0%. Mechanism investigation demonstrated flocs sizes distinctly declined, with more extracellular polymeric substances (EPS) released to resist FNA inactivation. Linear fitting showed NAP increased with FNA/MLVSS increment. Therefore, MLVSS affected FNA pretreatment performance, with FNA/MLVSS proposed as a more valuable criterion in FNA pretreatment strategy development, than the solely FNA.
Collapse
Affiliation(s)
- Zenghua Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Bo Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Xiaofei Gong
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Xin Qiao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China.
| |
Collapse
|
22
|
Wu Y, Song K, Sun X, Li L, Wang W, Wang Q, Wang D. Effects of free nitrous acid and freezing co-pretreatment on sludge short-chain fatty acids production and dewaterability. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 669:600-607. [PMID: 30889449 DOI: 10.1016/j.scitotenv.2019.03.175] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 03/12/2019] [Accepted: 03/12/2019] [Indexed: 06/09/2023]
Abstract
Short-chain fatty acids (SCFAs) as recoverable carbon source from waste activated sludge anaerobic fermentation process have aroused wide concern. In this study, free nitrous acid (FNA) and freezing pretreatments were combined to enhance SCFAs yield and fermented sludge dewaterability in the anaerobic fermentation system. The effects of different FNA concentrations and different freezing conditions (with or without curing stages) were analysed and compared. The results indicated that combining 1.07 mg N/L FNA with 48 h continuous freezing at -5 °C, raised SCFAs production from 6.7 mg COD/g volatile suspended solids (VSS) for the blank (no pretreatment) up to 124.0 mg COD/g VSS. In addition, the minimal water content of the treated fermented sludge cake was 78.11%, which was less than that of the blank (81.22%). SCFAs production and dewaterability enhancement could be attributed to sludge disintegration induced by the co-pretreatment, which led to sludge solubilisation, organics release, methanogenesis inhibition and particle size variation. This study implied that FNA and freezing co-pretreatment has the potential to enhance SCFAs production and sludge dewaterability in wastewater treatment plants.
Collapse
Affiliation(s)
- Yuqi Wu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Kang Song
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China.
| | - Xiaoyan Sun
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Lu Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Wenlin Wang
- Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing 210042, PR China
| | - Qilin Wang
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - Dongbo Wang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China
| |
Collapse
|
23
|
Wang X, Zhang L, Peng Y, Zhang Q, Li J, Yang S. Enhancing the digestion of waste activated sludge through nitrite addition: insight on mechanism through profiles of extracellular polymeric substances (EPS) and microbial communities. JOURNAL OF HAZARDOUS MATERIALS 2019; 369:164-170. [PMID: 30776599 DOI: 10.1016/j.jhazmat.2019.02.023] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 01/31/2019] [Accepted: 02/08/2019] [Indexed: 06/09/2023]
Abstract
Extracellular nitrite has been used to improve the digestion of waste activated sludge (WAS). However, the underlying mechanism remains largely unknown. In this study, WAS was treated with 0.2 gNO2--N/gVSS for 7 days and its performance was compared to that of aerobic and anaerobic treatments. The addition of nitrite had a distinct effect on the reduction of VSS/SS and the accumulation of soluble organics compared to the control reactors. As evident by the variations of extracellular polymeric substances (EPS), nitrite addition had a positive effect on decreasing protein. In particular, the decrease of protein mainly occurred in tightly bound EPS (TB-EPS), which caused sludge disintegration and enhanced sludge reduction. Additionally, the decrease of microbial diversity with nitrite addition was significant compared to the control reactors, accompany with a decrease of live/dead cells ratio and an increase of supernatant DNA concentration. This suggests that nitrite could cause cell death and lysis, resulting in sludge degradation. Thus, nitrite addition enhanced sludge treatment through the combined effect of TB-EPS disintegration and cell lysis. These findings will be useful for the optimization of sludge treatment process based on nitrite addition.
Collapse
Affiliation(s)
- Xiaoling Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing, 100124, PR China
| | - Liang Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing, 100124, PR China.
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing, 100124, PR China
| | - Qiong Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing, 100124, PR China
| | - Jialin Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing, 100124, PR China
| | - Shenhua Yang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing, 100124, PR China
| |
Collapse
|
24
|
Lu Y, Xu Y, Dong B, Dai X. Effects of free nitrous acid and nitrite on two-phase anaerobic digestion of waste activated sludge: A preliminary study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 654:1064-1071. [PMID: 30841381 DOI: 10.1016/j.scitotenv.2018.11.033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 11/02/2018] [Accepted: 11/02/2018] [Indexed: 06/09/2023]
Abstract
Nitrite, a product of the nitritation of sewage or digestion liquid, has been used to pretreat waste activated sludge (WAS) before anaerobic digestion. In this study, the effects of free nitrous acid (FNA) and nitrite on two-phase anaerobic sludge bioconversion were investigated. The experimental results indicated that both nitrite and FNA promoted sludge organic solubilization. Notably, nitrite promoted volatile fatty acids (VFAs) accumulation while FNA inhibited VFA accumulation in the first phase (acidogenic phase). In the second phase (methanogenic phase), neither nitrite nor FNA improved the net cumulative methane production from WAS. Although net cumulative methane production was not enhanced by the addition of nitrite or FNA, the volatile solids (VS) degradation rate was improved with nitrite addition in the two-phase anaerobic digestion process, indicating that nitrite is more favorable than FNA for the two-phase anaerobic digestion of WAS. It is expected that these findings can offer useful insights into future design of anaerobic digestion system with the treatment by the nitrite from digestion liquid.
Collapse
Affiliation(s)
- Yiqing Lu
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Ying Xu
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Bin Dong
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China.
| | - Xiaohu Dai
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| |
Collapse
|
25
|
Duan H, Ye L, Lu X, Batstone DJ, Yuan Z. Self-Sustained Nitrite Accumulation at Low pH Greatly Enhances Volatile Solids Destruction and Nitrogen Removal in Aerobic Sludge Digestion. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:1225-1234. [PMID: 30582696 DOI: 10.1021/acs.est.8b04498] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Aerobic sludge digestion of waste activated sludge (WAS) is widely used as a stabilization option in small- and midsized wastewater treatment plants. However, the digestion process is often limited by low volatile solids (VS) destruction and poor pathogen removal efficiency. This study presents a novel operational strategy that achieves enhanced VS destruction and nitrogen removal by inducing sustained nitrite accumulation via a single spike of nitrite to aerobic digester operated at a natively low pH (<5.5). The strategy was demonstrated through the use of three laboratory aerobic sludge digesters, each continuously operated for over 300 days. Compared to control reactors, the strategy enhanced volatile solids destruction by 35.0-38.4%, nitrogen removal by 58.5-70.8%, and pathogen reduction by approximately 1 log. The standard oxygen uptake rate (SOUR) was reduced to 0.49 ± 0.03 mgO2/gVS/h, compared to 0.85 ± 0.01-1.68 ± 0.02 mgO2/gVS/h in the control, indicating enhanced stabilization. Free nitrous acid formed from nitrite at low pH, rather than nitrite itself, was identified to be the cause of improved digestion performance. Since the nitrite production is self-supporting, no additional ongoing costs are incurred.
Collapse
Affiliation(s)
- Haoran Duan
- Advanced Water Management Centre , The University of Queensland , St. Lucia , Queensland 4072 , Australia
| | - Liu Ye
- School of Chemical Engineering , The University of Queensland , St. Lucia , Brisbane , Queensland 4072 , Australia
| | - Xuanyu Lu
- Advanced Water Management Centre , The University of Queensland , St. Lucia , Queensland 4072 , Australia
- School of Chemical Engineering , The University of Queensland , St. Lucia , Brisbane , Queensland 4072 , Australia
| | - Damien J Batstone
- Advanced Water Management Centre , The University of Queensland , St. Lucia , Queensland 4072 , Australia
| | - Zhiguo Yuan
- Advanced Water Management Centre , The University of Queensland , St. Lucia , Queensland 4072 , Australia
| |
Collapse
|
26
|
Chen H, Jin R, Liu G, Tian T, Gu C, Zhou J, Xing D. Effects of sludge lysate for Cr(VI) bioreduction and analysis of bioaugmentation mechanism of sludge humic acid. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:5065-5075. [PMID: 30604364 DOI: 10.1007/s11356-018-3917-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 12/04/2018] [Indexed: 06/09/2023]
Abstract
This study evaluated the effects of sludge lysate (SL) on the anaerobic bioreduction of Cr(VI) and the role of sludge humic acid (SHA) during this process. The results showed that supplement of SL significantly enhanced the efficiency of Cr(VI) bioreduction by 29.61%, in 12 h compared with that of the control without SL. Moreover, SHA exhibited promoting effects on bioreduction of Cr(VI), and the promotion increased with increasing SHA concentrations from 100 to 300 mg/L. In the presence of 300 mg/L SHA, Cr(VI) (98.21 mg/L) was completely reduced after 24 h with a removal rate increased by 34.3% compared with that of the control without SHA. Further investigation on the bioaugmentation mechanism of SHA by studying the nature of SHA and the reaction mechanism between SHA and Cr(VI) revealed that SHA exhibited a strong adsorption ability, which could adsorb and combine with Cr(VI). The adsorption capacity of Cr(VI) by SHA was calculated as 34.4 mg/g with 0.2 g of SHA and 10 mg/L of Cr(VI). It could also act as redox mediators to accelerate the electron transfer between microorganisms and Cr(VI) to promote reduction of Cr(VI). Furthermore, the effects of SL on the microbial community compositions of the anaerobic Cr(VI) bioreduction system were studied. Brachymonas was the primary bacteria at the genus level. The abundance of electroactive bacteria, such as Acinetobacter, Pseudomonas, and Arcobacter, increased in the SL-amended system. These findings expand the versatility of SL and justify wider use of residual activated sludge, which might contribute to the treatment of heavy metal-contaminated wastewater.
Collapse
Affiliation(s)
- Hongling Chen
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
- Drainage Management Office, Tongliao Municipal Commission of Housing Urban-Rural Development, Tongliao, 028000, China
| | - Ruofei Jin
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China.
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China.
| | - Guangfei Liu
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Tian Tian
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Chen Gu
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Jiti Zhou
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Defeng Xing
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China.
| |
Collapse
|
27
|
Chen J, Zhang S, Han X, Zhang L, Peng Y. Nitritation of real sewage: start-up and maintenance by the side-stream heat-shock treatment. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2019; 79:753-758. [PMID: 30975941 DOI: 10.2166/wst.2019.095] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In this study, the side-stream heat-shock treatment was used to start up and maintain the nitritation of real sewage. Complete nitrification was obtained when the real sewage was treated in a sequencing batch reactor (SBR). Then, about 50% of the mixed sludge was collected from the SBR and treated with the heat-shock treatment at 60 °C for 40 min in another reactor every 2 weeks. After providing the heat-shock treatment for four times, the effluent nitrate in the SBR gradually decreased from 22.5 to 3.2 mg/L, while the nitrite accumulation rate increased from 4.4% to 81.8%, indicating a successful start-up of nitritation. Further, the sewage nitritation was stable with the regular side-steam heat-shock treatment for 91 days, and the ammonium removal efficiency of 80.6% and nitrite accumulation rate of 91.2% were achieved. This study suggests that the side-stream heat-shock treatment could be used to start up sewage nitritation and maintain stability for a long-term operation.
Collapse
Affiliation(s)
- Jianfei Chen
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China E-mail:
| | - Shujun Zhang
- Beijing Drainage Group Co. Ltd (BDG), Beijing 100022, China
| | - Xiaoyu Han
- Beijing Drainage Group Co. Ltd (BDG), Beijing 100022, China
| | - Liang Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China E-mail:
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China E-mail:
| |
Collapse
|
28
|
Nan X, Ma B, Qian W, Zhu H, Li X, Zhang Q, Peng Y. Achieving nitritation by treating sludge with free nitrous acid: The effect of starvation. BIORESOURCE TECHNOLOGY 2019; 271:159-165. [PMID: 30268010 DOI: 10.1016/j.biortech.2018.09.113] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 09/20/2018] [Accepted: 09/21/2018] [Indexed: 06/08/2023]
Abstract
Side-stream sludge treatment using free nitrous acid (FNA) is a novel strategy to achieve nitritation in mainstream of wastewater treatment plants (WWTPs). To optimize nitritation, the effect of starvation on this strategy was investigated in this study. The results showed that pre-starvation, which is the starvation before FNA treatment, enhanced the resistance of sludge to FNA. This led to a decrease in the nitrite accumulation rate (NAR), which dropped from 70% to 27% after aerobic pre-starvation. This was further confirmed in the FNA treatment using the sludge collected from the secondary settling tank (anoxic pre-starvation) and the aerobic zone (without starvation) of an Anaerobic-Anoxic-Oxic system. The post-starvation, which was the starvation after FNA treatment, decreased NAR from 63% to 14%. To obtain a higher NAR, the sludge used for FNA treatment should be collected from aerobic zone, and be returned to aerobic zone after treatment to avoid pre-starvation and post-starvation.
Collapse
Affiliation(s)
- Xi Nan
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Bin Ma
- College of Environment and Ecology, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China; National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China.
| | - Wenting Qian
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Hongbo Zhu
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Xiyao Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Qiong Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| |
Collapse
|
29
|
Liao Q, Guo L, Ran Y, Gao M, She Z, Zhao Y, Liu Y. Optimization of polyhydroxyalkanoates (PHA) synthesis with heat pretreated waste sludge. WASTE MANAGEMENT (NEW YORK, N.Y.) 2018; 82:15-25. [PMID: 30509577 DOI: 10.1016/j.wasman.2018.10.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 09/03/2018] [Accepted: 10/11/2018] [Indexed: 06/09/2023]
Abstract
To reduce the cost of polyhydroxyalkanoates (PHA) production and disposal amount of waste sludge simultaneously, the feasibility of using different heat pretreated sludge (60 °C, 80 °C, 100 °C, 120 °C) as external carbon source to synthesize PHA was examined in this study. The maximal PHA accumulation (24.1% of the dry cell weight) was achieved with 60 °C pretreated waste sludge, with the utilization efficiency of COD, proteins, carbohydrate and VFAs were 74.3%, 82.3%,47.2%,81.4%, respectively. Both of VFAs and non VFAs organics could be used as carbon source for PHA synthesis. The results of kinetic parameter analysis showed that the highest PHA production rate (0.23 mg COD/mg X·h) and the PHA conversion rate (0.46 mg COD/mg COD) all occurred when using 60 °C pretreated waste sludge. In order to further investigate the utilization of sludge carbon source for PHA synthesis, the three-dimensional fluorescence excitation-emission matrix (EEM) spectroscopy with fluorescence regional integration (FRI) analysis were introduced.
Collapse
Affiliation(s)
- Qianru Liao
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Liang Guo
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China; Key Laboratory of Marine Environmental and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100, China.
| | - Yihe Ran
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Mengchun Gao
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Zonglian She
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Yangguo Zhao
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Yiping Liu
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| |
Collapse
|
30
|
Wang Y, Zhao J, Wang D, Liu Y, Wang Q, Ni BJ, Chen F, Yang Q, Li X, Zeng G, Yuan Z. Free nitrous acid promotes hydrogen production from dark fermentation of waste activated sludge. WATER RESEARCH 2018; 145:113-124. [PMID: 30121432 DOI: 10.1016/j.watres.2018.08.011] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Revised: 07/10/2018] [Accepted: 08/02/2018] [Indexed: 06/08/2023]
Abstract
Simultaneous sludge fermentation and nitrite removal is an effective approach to enhance nutrient removal from low carbon-wastewater. It was found in this work that the presence of nitrite largely promoted hydrogen production from acidic fermentation of waste activated sludge (WAS). The results showed that with an increase of nitrite from 0 to 250 mg/L, the maximal hydrogen yield increased from 8.5 to 15.0 mL/g VSS at pH 5.5 fermentation and 8.1-13.0 mL/g VSS at pH 6 fermentation. However, the maximal hydrogen yield from WAS fermentation at pH 8 remained almost constant (2.9-3.7 mL/g VSS) when nitrite was in the range of 0-250 mg/L. Further analyses revealed that free nitrous acid (FNA) rather than nitrite was the major contributor to the promotion of hydrogen yield. The mechanism investigations showed that FNA not only accelerated the disruption of sludge cells but also promoted the biodegradability of organics released, thereby provided more biodegradable substrates for subsequent hydrogen production. Although FNA inhibited activities of all microbes involved in the anaerobic fermentation, its inhibitions to hydrogen consumers were much severer than those to hydrolytic microorganisms and hydrogen producers. Further investigations with microbial community showed that FNA increased the abundances of hydrogen producers (e.g., Citrobacter sp.) and denitrifiers (e.g., Dechloromonas sp.), but reduced the abundances of hydrogen consumers (e.g., Clostridium_aceticum). This work demonstrated for the first time that FNA in WAS fermentation systems enhanced hydrogen production. The findings obtained expand the application field of FNA and may provide supports for sustainable operation of wastewater treatment plants.
Collapse
Affiliation(s)
- Yali Wang
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China.
| | - Jianwei Zhao
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China
| | - Dongbo Wang
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China.
| | - Yiwen Liu
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia
| | - Qilin Wang
- Griffith School of Engineering & Centre for Clean Environment and Energy, Griffith University, QLD, Australia
| | - Bing-Jie Ni
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia
| | - Fei Chen
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China
| | - Qi Yang
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China
| | - Xiaoming Li
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China
| | - Guangming Zeng
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China
| | - Zhiguo Yuan
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Brisbane, Queensland, 4072, Australia.
| |
Collapse
|
31
|
Jin B, Niu J, Dai J, Li N, Zhou P, Niu J, Zhang J, Tao H, Ma Z, Zhang Z. New insights into the enhancement of biochemical degradation potential from waste activated sludge with low organic content by Potassium Monopersulfate treatment. BIORESOURCE TECHNOLOGY 2018; 265:8-16. [PMID: 29864736 DOI: 10.1016/j.biortech.2018.05.032] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 05/07/2018] [Accepted: 05/08/2018] [Indexed: 06/08/2023]
Abstract
Waste activated sludge with low organic content (WAS-LOC) always led to the failure of anaerobic fermentation. A potentially practical technology based on SO4-, i.e. Potassium Monopersulfate (PMS) was used into WAS-LOC anaerobic fermentation system and had been presented to greatly improve both the intracellular and extracellular constituents, which improved the biological enzyme activity and produced a mass of short-chain fatty acids (SCFAs). Results showed that the maximal SCFAs production was 716.72 mg chemical oxygen demand (COD)/L (0.08 mg PMS/mg SS), which increased to 43.70 times comparing to that of 0.00 mg PMS/mg SS level (16.40 mgCOD/L). The activities of biological enzymes increased 1.42 times for protease, 4.38 times for α-glucosidase, 2.1 times for alkaline phosphatase, 1.70 times for acidic phosphatase and 1.37 times for dehydrogenase respectively comparing to natural fermentation system, but the coenzyme 420 was restrained prominently. PMS positively enriched the abundance of microbial community responsible for WAS-LOC hydrolysis and SCFAs production.
Collapse
Affiliation(s)
- Baodan Jin
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou 450001, China.
| | - Jintao Niu
- HE NAN GENGAN HUANBAO KEJIYOUXIANGONGSI, Zhengzhou 450001, China
| | - Jingwen Dai
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou 450001, China
| | - Nuonan Li
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou 450001, China
| | - Ping Zhou
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou 450001, China
| | - Jiahui Niu
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou 450001, China
| | - Ju Zhang
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou 450001, China
| | - Hongfan Tao
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou 450001, China
| | - Zhigang Ma
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou 450001, China
| | - Zhongfang Zhang
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou 450001, China
| |
Collapse
|
32
|
Hallaji SM, Torabian A, Aminzadeh B, Zahedi S, Eshtiaghi N. Improvement of anaerobic digestion of sewage mixed sludge using free nitrous acid and Fenton pre-treatment. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:233. [PMID: 30181773 PMCID: PMC6112153 DOI: 10.1186/s13068-018-1235-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Accepted: 08/22/2018] [Indexed: 05/16/2023]
Abstract
BACKGROUND Recently, it has been indicated that free nitrous acid (FNA) and Fenton pre-treatment of waste activated sludge can enhance methane production in anaerobic digestion of waste activated sludge. In addition, it has been revealed that the substances used in these pre-treatments are both eco-friendly and economically attractive because not only are they produced in anaerobic digestion, but they are also low priced. Since primary sludge and waste activated sludge are mixed prior to anaerobic digestion in the majority of wastewater treatment plants, this study aims to assess the influence of combined FNA and Fenton on the anaerobic digestion of mixed sludge. RESULTS According to this study's results, methane generation from anaerobic digestion of mixed sludge was enhanced when using FNA and Fenton pre-treatment, affirming the effectiveness of the individual and combined pre-treatments in anaerobic digestion of mixed sludge. The enhanced methane production was significant in combined pre-treatments (up to 72%), compared with FNA and Fenton pre-treatment alone (25% and 27%, respectively). This corroborates the positive synergistic effect of the combined pre-treatments on methane production. The enhanced methane can be attributed to augmented soluble fractions of organic matter in addition to increased readily biodegradable organic matter, caused by the pre-treatments. Additionally, the amount of chemical oxygen demand (COD) was assessed during anaerobic digestion, and it was revealed that COD decreased considerably when the pre-treatment strategies were combined. CONCLUSIONS This study reveals that the pre-treatments are potentially applicable to full-scale wastewater treatment plants because a mixture of primary sludge and waste activated sludge was used for the pre-treatments. Additionally, combined FNA and Fenton pre-treatments prove more effective in enhancing methane production and organic removal than these pre-treatments alone. The enhanced methane production is important for two reasons: a higher amount of renewable energy could be generated from the enhanced methane production and the COD of digested sludge reduces in such a way that facilitates application of the sludge to agricultural lands and reduces sludge transport costs.
Collapse
Affiliation(s)
| | - Ali Torabian
- School of Environment, College of Engineering, University of Tehran, Tehran, Iran
| | - Behnoush Aminzadeh
- School of Environment, College of Engineering, University of Tehran, Tehran, Iran
| | - Soraya Zahedi
- Catalan Institute for Water Research (ICRA), Girona, Spain
| | - Nicky Eshtiaghi
- School of Engineering, Chemical and Environmental Engineering, RMIT University, Melbourne, Australia
| |
Collapse
|
33
|
Yang G, Xu Q, Wang D, Tang L, Xia J, Wang Q, Zeng G, Yang Q, Li X. Free ammonia-based sludge treatment reduces sludge production in the wastewater treatment process. CHEMOSPHERE 2018; 205:484-492. [PMID: 29705639 DOI: 10.1016/j.chemosphere.2018.04.140] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 04/14/2018] [Accepted: 04/21/2018] [Indexed: 06/08/2023]
Abstract
Excessive sludge production is one of the major challenges for biological wastewater treatment plants. This paper reports a new strategy to enhance sludge reduction from the wastewater treatment process. In this strategy, 1/5 of the sludge is withdrawn from the mainstream reactor into a side-stream unit for sludge treatment with 16 mg/L free ammonia (FA) for 24-40 h. The FA-treated sludge mixture is then returned to the mainstream reactor. To demonstrate this concept, two reactors treating synthetic domestic wastewater were operated, with one serving as the experimental reactor and the other as the control. Experimental results showed that the experimental reactor exhibited 20% lower in sludge production than the control. FA treatment effectively disintegrated a portion of extracellular or intracellular substances of sludge cells in the FA treatment unit and lowered the observed sludge yields in the mainstream reactor, which were the main reasons for the sludge reduction. Although FA treatment decreased the activities of nitrifiers, denitrifiers, and polyphosphate accumulating organisms in the FA treatment unit, this strategy did not negatively affect the reactor performance and sludge properties of the experimental reactor such as sludge settleability, organic removal, nitrogen removal and phosphorus removal. Further investigation showed that the organics released from the FA treatment process could be used by PAOs and denitrifiers for carbon sources.
Collapse
Affiliation(s)
- Guojing Yang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China; College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo 315100, PR China
| | - Qiuxiang Xu
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Dongbo Wang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
| | - Li Tang
- College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo 315100, PR China
| | - Jingfen Xia
- College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo 315100, PR China
| | - Qilin Wang
- Griffith School of Engineering & Centre for Clean Environment and Energy, Griffith University, QLD, Australia
| | - Guangming Zeng
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Qi Yang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
| | - Xiaoming Li
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| |
Collapse
|
34
|
Guo L, Guo Y, Sun M, Gao M, Zhao Y, She Z. Enhancing denitrification with waste sludge carbon source: the substrate metabolism process and mechanisms. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:13079-13092. [PMID: 29484622 DOI: 10.1007/s11356-017-0836-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 11/23/2017] [Indexed: 06/08/2023]
Abstract
Using waste sludge internal carbon source for nitrogen removal in wastewater has drawn much attention, due to its economic advantages and sludge reduction. In this study, the performance of enhanced denitrification with waste sludge thermal hydrolysate and fermentation liquid as carbon sources at different SCOD/N (soluble chemical oxygen demand/NO3--N) was investigated. The optimum SCOD/N was 8 for sludge thermal hydrolysate and 7 for fermentation liquid, with NO3--N removal efficiency of 92.3 and 98.9%, respectively, and no NO2--N accumulation. To further understand the fate of sludge carbon source during denitrification, the changes of SCOD, proteins, carbohydrates, and volatile fatty acids (VFAs) were analyzed, and three-dimensional fluorescence excitation-emission matrix (EEM) spectroscopy with fluorescence regional integration (FRI) analysis was introduced. The utilization of SCOD was consistent with NO3--N reduction, and the utilization efficiency of different organic matter was as follows: VFAs > proteins > carbohydrates. The soluble organic-like materials (region IV) were the most readily utilized organic matter according to three-dimensional fluorescence EEM spectroscopy. Regarding denitrification mechanisms, the denitrification rate (VDN), denitrification potential (PDN), heterotroph anoxic yield (YH), and the most readily biodegradable COD (SS) were also investigated.
Collapse
Affiliation(s)
- Liang Guo
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China.
- Key Laboratory of Marine Environmental and Ecology, Ministry of Education, Ocean University of China, Qingdao, 266100, China.
| | - Yiding Guo
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Mei Sun
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Mengchun Gao
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Yangguo Zhao
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Zonglian She
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| |
Collapse
|
35
|
Wang J, Zhang Z, Ye X, Huang F, Chen S. Performance and mechanism of free nitrous acid on the solubilization of waste activated sludge. RSC Adv 2018; 8:15897-15905. [PMID: 35542244 PMCID: PMC9080090 DOI: 10.1039/c8ra01951g] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 04/17/2018] [Indexed: 11/21/2022] Open
Abstract
Free nitrous acid (FNA) is a promising chemical reagent for excess sludge reduction. The distinctive properties of FNA treatment on waste activated sludge (WAS) disposal have previously been demonstrated, however, the cellular response, permeabilization, and disruption caused by low-concentration FNA and the direct cell solubilization of WAS using concentrated FNA should be better understood. In this study, the parameters that influence the sludge solubilization efficiency were optimized over a wide range of FNA concentrations. The sludge solubilization efficiency was found to be superior when the sludge was exposed to FNA (when the dosage of NaNO2 was 0.12 g g-1 TSS and the pH was 3.0, FNA = 20.94 mg L-1) for 10 h at 25 °C, and the TSS removal and COD dissolution efficiencies were found to be prominent at 38% and 7%, respectively. In the FNA treatment of WAS, some FNA-tolerable cells increased the K+, Ca2+, and H+ effluxes under low concentrations of FNA, and finally achieved ion homeostasis based on the results using a scanning ion-selective electrode measurement technique. This could cause the cells in WAS to maintain cytoactivity and integrity under a low-concentration FNA treatment. Furthermore, flow cytometry was used to assess the permeabilization and disruption of sludge cells toward a concentration gradient of FNA. Flow cytometry results indicated that cells in sludge flocs were disrupted within 30 minutes when the FNA concentration was above 8 mg L-1.
Collapse
Affiliation(s)
- Jinsong Wang
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences Xiamen 361021 China +86 0592 6190977 +86 0592 6190529
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Zhaoji Zhang
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences Xiamen 361021 China +86 0592 6190977 +86 0592 6190529
| | - Xin Ye
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences Xiamen 361021 China +86 0592 6190977 +86 0592 6190529
| | - Fuyi Huang
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences Xiamen 361021 China +86 0592 6190977 +86 0592 6190529
| | - Shaohua Chen
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences Xiamen 361021 China +86 0592 6190977 +86 0592 6190529
| |
Collapse
|
36
|
Zahedi S, Romero-Güiza M, Icaran P, Yuan Z, Pijuan M. Optimization of free nitrous acid pre-treatment on waste activated sludge. BIORESOURCE TECHNOLOGY 2018; 252:216-220. [PMID: 29306612 DOI: 10.1016/j.biortech.2017.12.090] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Revised: 12/26/2017] [Accepted: 12/27/2017] [Indexed: 06/07/2023]
Abstract
The effectiveness of the Free Nitrous Acid (FNA) sludge treatment was tested in the range from 0 to 3.0 mg N-HNO2/L with acidified and neutral pH. 4 h pre-treatment times were used and the specific methane production (SMP) investigated. Results show that between 50 and 100 mg/L of N-NO2-/L disappeared during the FNA pre-treatment, reducing its effectiveness. A minimum level of nitrite (174 mg N-NO2-/L tested in this study), independently of pH/FNA, was necessary to assure the presence of the chemical throughout the duration of the pre-treatment. Sludge viability was compromised while WAS solubilization and SMP were enhanced with nitrite concentrations of 174 mg N-NO2-/L or higher, even at low FNA levels (<0.15 mg N-HNO2/L). Results show that acidified pH is not needed to enhance methane production, making the pretreatment more economically and environmentally attractive.
Collapse
Affiliation(s)
- S Zahedi
- Catalan Institute for Water Research (ICRA), Emili Grahit Street, 101, H(2)O Building. Scientific and Technological Park of the University of Girona, 17003 Girona, Spain.
| | - M Romero-Güiza
- Department of Innovation and Technology, FCC Aqualia, Balmes Street, 36, 6thfloor, 08007 Barcelona, Spain
| | - Pilar Icaran
- Department of Innovation and Technology, FCC Aqualia, Balmes Street, 36, 6thfloor, 08007 Barcelona, Spain
| | - Z Yuan
- Advanced Water Management Centre, The University of Queensland, St Lucia 4072, Australia
| | - M Pijuan
- Catalan Institute for Water Research (ICRA), Emili Grahit Street, 101, H(2)O Building. Scientific and Technological Park of the University of Girona, 17003 Girona, Spain.
| |
Collapse
|
37
|
Wang Z, Zhang S, Zhang L, Wang B, Liu W, Ma S, Peng Y. Restoration of real sewage partial nitritation-anammox process from nitrate accumulation using free nitrous acid treatment. BIORESOURCE TECHNOLOGY 2018; 251:341-349. [PMID: 29291531 DOI: 10.1016/j.biortech.2017.12.073] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 12/18/2017] [Accepted: 12/25/2017] [Indexed: 06/07/2023]
Abstract
This study presented a strategy for recovering partial nitritation-anammox (PN/A) of real sewage from nitrate accumulation using free nitrous acid (FNA) treatment. Sewage PN/A was successfully achieved in an integrated fixed-film activated sludge (IFAS) reactor but effluent nitrate gradually increased. For recovering the system performance, flocculent sludge of the reactor was collected and treated with FNA of 1.35 mg/L for 24 h. After FNA treatment, effluent nitrate decreased from 17.6 to 6.1 mg/L with an increase of total nitrogen removal efficiency from 29.1% to 63.1% within 32 days. The improvement of nitrogen removal was mainly due to the selective suppression of FNA on nitrite-oxidizing bacteria. Its relative abundance decreased from 0.32% to 0.08% and the activity declined from 9.05 to 2.42 mg N/(g MLSS·h). Meanwhile, ammonium-oxidizing bacteria and anammox bacteria were barely affected. Overall, IFAS reactor combined with FNA treatment potentially provided a promising technology for stable operation of one-stage sewage PN/A.
Collapse
Affiliation(s)
- Zhibin Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Shujun Zhang
- Beijing Drainage Group Co. Ltd (BDG), Beijing 100022, China
| | - Liang Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China.
| | - Bo Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Wenlong Liu
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Shuqing Ma
- Beijing Drainage Group Co. Ltd (BDG), Beijing 100022, China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| |
Collapse
|
38
|
Sun F, Xiao K, Zhu W, Withanage N, Zhou Y. Enhanced sludge solubilization and dewaterability by synergistic effects of nitrite and freezing. WATER RESEARCH 2018; 130:208-214. [PMID: 29223781 DOI: 10.1016/j.watres.2017.11.066] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Revised: 10/30/2017] [Accepted: 11/29/2017] [Indexed: 05/21/2023]
Abstract
In this study, nitrite was added into sludge during freezing process to evaluate its role in waste activated sludge (WAS) solubilization and effect on sludge dewatering characteristics. The results showed that the introduction of 100 mg L-1 of nitrite could increase dissolved organic carbon (DOC) concentration from 29.5 to 48.8 mg DOC g-1 VSS under freezing conditions. More DOC was released with the increase of nitrite concentration. Freezing temperature, or freezing speed, also played a role in sludge solubilization. It was found that some readily-biodegradable low molecular weight (LMW) compounds, e.g. LMW protein, LMW polysaccharide, LMW neutrals, building blocks and LMW acids, were mainly released during the freezing process with the presence of nitrite. Interestingly, nitrite could also improve the sludge filterability at the lower nitrite concentration as a result of the increased sludge particle size. However, electrolytes (sodium nitrite) addition effects may mask such enhancement when nitrite concentration was high (800 mg L-1). The rheological characteristics of sludge could be well modeled by Herchel-Bulkley model and the introduction of nitrite into freezing process further increased sludge flowability and decreased sludge viscosity. These results indicated that freezing with the presence of suitable concentration of nitrite could promote sludge solubilization and dewaterability. As such, good liquid and solid separation can be achieved with the recovery of liquid stream as carbon source.
Collapse
Affiliation(s)
- Faqian Sun
- School of Civil and Environmental Engineering, Nanyang Technological University, 639798, Singapore; Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 637141, Singapore
| | - KeKe Xiao
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 637141, Singapore
| | - Wenyu Zhu
- School of Civil and Environmental Engineering, Nanyang Technological University, 639798, Singapore; Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 637141, Singapore
| | - Nipuna Withanage
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 637141, Singapore
| | - Yan Zhou
- School of Civil and Environmental Engineering, Nanyang Technological University, 639798, Singapore; Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 637141, Singapore.
| |
Collapse
|
39
|
Wu C, Zhou Y, Zhang S, Xu M, Song J. The effect of toxic carbon source on the reaction of activated sludge in the batch reactor. CHEMOSPHERE 2018; 194:784-792. [PMID: 29253823 DOI: 10.1016/j.chemosphere.2017.12.075] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 11/12/2017] [Accepted: 12/11/2017] [Indexed: 06/07/2023]
Abstract
The toxic carbon source can cause higher residual effluent dissolved organic carbon than easily biodegraded carbon source in activated sludge process. In this study, an integrated activated sludge model is developed as the tool to understand the mechanism of toxic carbon source (phenol) on the reaction, regarding the carbon flows during the aeration period in the batch reactor. To estimate the toxic function of phenol, the microbial cells death rate (kdeath) is introduced into the model. The integrated model was calibrated and validated by the experimental data and it was found the model simulations matched the all experimental measurements. In the steady state, the toxicity of phenol can result in higher microbial cells death rate (0.1637 h-1 vs 0.0028 h-1) and decay rate coefficient of biomass (0.0115 h-1 vs 0.0107 h-1) than acetate. In addition, the utilization-associated products (UAP) and extracellular polymeric substances (EPS) formation coefficients of phenol are higher than that of acetate, indicating that more carbon flows into the extracellular components, such as soluble microbial products (SMP), when degrading toxic organics. In the non-steady state of feeding phenol, the yield coefficient for growth and maximum specific growth rate are very low in the first few days (1-10 d), while the decay rate coefficient of biomass and microbial cells death rate are relatively high. The model provides insights into the difference of the dynamic reaction with different carbon sources in the batch reactor.
Collapse
Affiliation(s)
- Changyong Wu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Research Center of Water Pollution Control Technology, Chinese Research Academy of Environment Sciences, Beijing 100012, China.
| | - Yuexi Zhou
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Research Center of Water Pollution Control Technology, Chinese Research Academy of Environment Sciences, Beijing 100012, China.
| | - Siyu Zhang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; School of Chemical and Environmental Engineering, China University of Mining and Technology, Beijing 100083, China
| | - Min Xu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; College of Water Science, Beijing Normal University, Beijing 100875, China
| | - Jiamei Song
- Research Center of Water Pollution Control Technology, Chinese Research Academy of Environment Sciences, Beijing 100012, China
| |
Collapse
|
40
|
Perez-Garcia O, Mankelow C, Chandran K, Villas-Boas SG, Singhal N. Modulation of Nitrous Oxide (N 2O) Accumulation by Primary Metabolites in Denitrifying Cultures Adapting to Changes in Environmental C and N. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:13678-13688. [PMID: 29083886 DOI: 10.1021/acs.est.7b03345] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Metabolomics provides insights into the actual physiology of cells rather than their mere "potential", as provided by genomic and transcriptomic analysis. We investigate the modulation of nitrous oxide (N2O) accumulation by intracellular metabolites in denitrifying bacteria using metabolomics and genome-based metabolic network modeling. Profiles of metabolites and their rates of production/consumption were obtained for denitrifying batch cultures under four conditions: initial COD:N ratios of 11:1 and 4:1 with and without nitrite spiking (28 mg-N L-1). Only the nitrite-spiked cultures accumulated N2O. The NO2- spiked cultures with an initial COD:N = 11:1 accumulated 3.3 ± 0.57% of the total nitrogen added as N2O and large pools of tricarboxylic acid cycle intermediates and amino acids. In comparison, the NO2- spiked cultures with COD:N = 4:1 showed significantly higher (p = 0.028) N2O accumulation (8.5.3 ± 0.9% of the total nitrogen added), which was linked to the depletion of C11-C20 fatty acids. Metabolic modeling analysis shows that at COD:N of 4:1 the denitrifying cells slowly generate electron equivalents as FADH2 through β-oxidation of saturated fatty acids, while COD:N of 11:1 do it through the TCA cycle. When combined with NO2- shock, this prolonged the duration over which insufficient electron equivalents were available to completely reduce NOx to N2, resulting in increased N2O accumulation. Results extend the understanding of how organic carbon and nitrite loads modulate N2O accumulation in denitrification, which may contribute to further design strategies to control greenhouse gas emissions from agricultural soils or wastewater treatment systems.
Collapse
Affiliation(s)
- Octavio Perez-Garcia
- Department of Civil and Environmental Engineering, University of Auckland , Private Bag 92019, Auckland 1142, New Zealand
| | - Cody Mankelow
- Department of Civil and Environmental Engineering, University of Auckland , Private Bag 92019, Auckland 1142, New Zealand
| | - Kartik Chandran
- Department of Earth and Environmental Engineering, Columbia University , New York, New York 10027, United States
| | - Silas G Villas-Boas
- School of Biological Sciences, University of Auckland , Private Bag 92019, Auckland 1010, New Zealand
| | - Naresh Singhal
- Department of Civil and Environmental Engineering, University of Auckland , Private Bag 92019, Auckland 1142, New Zealand
| |
Collapse
|
41
|
Ma B, Yang L, Wang Q, Yuan Z, Wang Y, Peng Y. Inactivation and adaptation of ammonia-oxidizing bacteria and nitrite-oxidizing bacteria when exposed to free nitrous acid. BIORESOURCE TECHNOLOGY 2017; 245:1266-1270. [PMID: 28893505 DOI: 10.1016/j.biortech.2017.08.074] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 08/09/2017] [Accepted: 08/13/2017] [Indexed: 06/07/2023]
Abstract
Inactivation and adaptation of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) to free nitrous acid (FNA) was investigated. Batch test results showed that AOB and NOB were inactivated when treated with FNA. After an 85-day operating period, AOB in a continuous pre-denitrification reactor did not adapt to the FNA that was applied to treat some of the return activated sludge. In contrast, NOB did adapt to FNA. NOB activity in the seed sludge was only 11% of the original activity after FNA batch treatment, at 0.75mg HNO2-N/L. NOB activity in the pre-denitrification reactor was not affected after being exposed to this FNA level. Nitrosomonas was the dominant AOB before and after long-term FNA treatment. However, dominant NOB changed from Nitrospira to Candidatus Nitrotoga, a novel NOB genus, after long-term FNA treatment. This adaptation of NOB to FNA may be due to the shift in NOB population makeup.
Collapse
Affiliation(s)
- Bin Ma
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, PR China
| | - Lan Yang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, PR China
| | - Qilin Wang
- Advanced Water Management Center, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Zhiguo Yuan
- Advanced Water Management Center, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Yayi Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, PR China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, PR China.
| |
Collapse
|
42
|
Zahedi S, Icaran P, Yuan Z, Pijuan M. Exploring alternatives to reduce economical costs associated with FNA pre-treatment of waste activated sludge. BIORESOURCE TECHNOLOGY 2017; 243:315-318. [PMID: 28683383 DOI: 10.1016/j.biortech.2017.06.140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 06/19/2017] [Accepted: 06/23/2017] [Indexed: 06/07/2023]
Abstract
Recent studies have shown the effectiveness of Free Nitrous Acid (FNA) pre-treatment in enhancing sludge biodegradability and improving its methane production potential. FNA is regarded as an environmental friendly pre-treatment which can be easily applied when a source of nitrite is present in wastewater treatment plants. However, when nitrite is not available and needs to be purchased, this treatment can become less attractive due to the costs associated to nitrite. In order to overcome this possible limitation, two different strategies to optimize the use of nitrite during FNA treatment were investigated: i) Recovering NO2- after the pre-treatment is completed; and ii) Concentrating the sludge before FNA pre-treatment. Results show that recovering NO2- from the pre-treated sludge is not suitable due to the loss of soluble organic matter present in the supernatant after the pre-treatment. However, concentrating the sludge before the pre-treatment seems a good strategy to optimize the use of nitrite.
Collapse
Affiliation(s)
- S Zahedi
- Catalan Institute for Water Research (ICRA), Emili Grahit Street, 101, H(2)O Building, Scientific and Technological Park of the University of Girona, 17003 Girona, Spain.
| | - P Icaran
- Department of Innovation and Technology, FCC Aqualia, Balmes Street, 36, 6th floor, 08007 Barcelona, Spain.
| | - Z Yuan
- Advanced Water Management Centre, The University of Queensland, St Lucia 4072, Australia.
| | - M Pijuan
- Catalan Institute for Water Research (ICRA), Emili Grahit Street, 101, H(2)O Building, Scientific and Technological Park of the University of Girona, 17003 Girona, Spain.
| |
Collapse
|
43
|
Zahedi S, Icaran P, Yuan Z, Pijuan M. Effect of free nitrous acid pre-treatment on primary sludge at low exposure times. BIORESOURCE TECHNOLOGY 2017; 228:272-278. [PMID: 28081525 DOI: 10.1016/j.biortech.2016.12.117] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 12/28/2016] [Accepted: 12/31/2016] [Indexed: 05/28/2023]
Abstract
The present study was undertaken to investigate the effect of different free nitrous acid (FNA) concentrations at low pre-treatment times (PTs) (1, 2 and 5h) and without pH control with mild agitation on primary sludge (PS) biodegradability and methane production (MP). Increasing PTs resulted in an increase in the solubility of the organic matter (around 25%), but not on cell-mortality (>75% in all the cases with FNA) and neither on methane generation. FNA pre-treatment at low PTs improve MP (around 16% at PT of 1h and 650mg N-NO2-/L). However, a similar improvement was found with mild agitation of PS without FNA at 2 and 5h. Taking into account the potential costs associated with the FNA pre-treatment, a mild agitation without FNA would be preferred to enhance MP in PS.
Collapse
Affiliation(s)
- S Zahedi
- Catalan Institute for Water Research (ICRA), Emili Grahit Street, 101, H(2)O Building, Scientific and Technological Park of the University of Girona, 17003 Girona, Spain.
| | - P Icaran
- Department of Innovation and Technology, FCC Aqualia, Balmes Street, 36, 6th Floor, 08007 Barcelona, Spain.
| | - Z Yuan
- Advanced Water Management Centre, The University of Queensland, St Lucia 4072, Australia.
| | - M Pijuan
- Catalan Institute for Water Research (ICRA), Emili Grahit Street, 101, H(2)O Building, Scientific and Technological Park of the University of Girona, 17003 Girona, Spain.
| |
Collapse
|
44
|
Guo Y, Guo L, Sun M, Zhao Y, Gao M, She Z. Effects of hydraulic retention time (HRT) on denitrification using waste activated sludge thermal hydrolysis liquid and acidogenic liquid as carbon sources. BIORESOURCE TECHNOLOGY 2017; 224:147-156. [PMID: 27913171 DOI: 10.1016/j.biortech.2016.11.056] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Revised: 11/10/2016] [Accepted: 11/13/2016] [Indexed: 05/22/2023]
Abstract
Waste activated sludge (WAS) internal carbon source can efficiently and economically enhance denitrification, and hydraulic retention time (HRT) is one of the most important operational parameters for denitrification. The effects of HRT on denitrification were investigated with WAS thermal hydrolysis liquid and acidogenic liquid as carbon sources in this study. The optimal HRT was 12h for thermal hydrolysis liquid and 8h for acidogenic liquid, with NO3--N removal efficiency of 91.0% and 97.6%, respectively. In order to investigate the utilization of sludge carbon source by denitrifier, the changes of SCOD (Soluble chemical oxygen demand), proteins, carbohydrates, and VFAs (Volatile fatty acids) during denitrification process were analyzed and three-dimensional fluorescence excitation-emission matrix (EEM) spectroscopy with fluorescence regional integration (FRI) analysis was introduced. The kinetics parameters of denitrification rate (VDN), denitrification potential (PDN) and heterotroph anoxic yield (YH) were also investigated using sludge carbon source at different HRT.
Collapse
Affiliation(s)
- Yiding Guo
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Liang Guo
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China; Key Laboratory of Marine Environmental and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100, China; Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering, Qingdao 266100, China.
| | - Mei Sun
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Yangguo Zhao
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Mengchun Gao
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Zonglian She
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| |
Collapse
|
45
|
Zahedi S, Icaran P, Yuan Z, Pijuan M. Assessment of free nitrous acid pre-treatment on a mixture of primary sludge and waste activated sludge: Effect of exposure time and concentration. BIORESOURCE TECHNOLOGY 2016; 216:870-5. [PMID: 27318660 DOI: 10.1016/j.biortech.2016.06.038] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 06/10/2016] [Accepted: 06/12/2016] [Indexed: 05/28/2023]
Abstract
Free nitrous acid (FNA) has been shown to enhance the biodegradability of waste activated sludge (WAS) but its effectiveness on the pre-treatment of mixed sludge is not known. This study explores the effectiveness of four different FNA concentrations (0, 2.49, 3.55, 4.62mgN-HNO2/L) and three exposure times (2, 5, 9h) lower than the ones reported in literature (24h) on WAS characteristics and specific methane production (SMP). FNA pre-treatment reduced sludge cell viability below 10% in all cases after an exposure time of 5h, increasing the solubility of the organic matter. The treated mixed sludge was used as substrate for the biochemical methane production tests to assess its SMP. Results showed a significant increase (up to 25%) on SMP when the sludge was pretreated with the lowest FNA concentration (2.49mgN-HNO2/L) during 2 and 5h but did not show any improvement at longer exposure times or higher FNA concentrations.
Collapse
Affiliation(s)
- S Zahedi
- Catalan Institute for Water Research (ICRA), Emili Grahit Street, 101, H(2)O Building, Scientific and Technological Park of the University of Girona, 17003 Girona, Spain
| | - P Icaran
- Department of Innovation and Technology, FCC Aqualia, Balmes Street, 36, 6th Floor, 08007 Barcelona, Spain
| | - Z Yuan
- Advanced Water Management Centre, The University of Queensland, St Lucia 4072, Australia
| | - M Pijuan
- Catalan Institute for Water Research (ICRA), Emili Grahit Street, 101, H(2)O Building, Scientific and Technological Park of the University of Girona, 17003 Girona, Spain.
| |
Collapse
|
46
|
Zhao J, Liu Y, Ni B, Wang Q, Wang D, Yang Q, Sun Y, Zeng G, Li X. Combined Effect of Free Nitrous Acid Pretreatment and Sodium Dodecylbenzene Sulfonate on Short-Chain Fatty Acid Production from Waste Activated Sludge. Sci Rep 2016; 6:21622. [PMID: 26868898 PMCID: PMC4751509 DOI: 10.1038/srep21622] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Accepted: 01/20/2016] [Indexed: 11/09/2022] Open
Abstract
Free nitrous acid (FNA) serving as a pretreatment is an effective approach to accelerate sludge disintegration. Also, sodium dodecylbenzene sulfonate (SDBS), a type of surfactants, has been determined at significant levels in sewage sludge, which thereby affects the characteristics of sludge. Both FNA pretreatment and sludge SDBS levels can affect short-chain fatty acid (SCFA) generation from sludge anaerobic fermentation. To date, however, the combined effect of FNA pretreatment and SDBS presence on SCFA production as well as the corresponding mechanisms have never been documented. This work therefore aims to provide such support. Experimental results showed that the combination of FNA and SDBS treatment not only improved SCFA accumulation but also shortened the fermentation time. The maximal SCFA accumulation of 334.5 mg chemical oxygen demand (COD)/g volatile suspended solids (VSS) was achieved at 1.54 mg FNA/L treatment and 0.02 g/g dry sludge, which was respectively 1.79-fold and 1.41-fold of that from FNA treatment and sludge containing SDBS alone. Mechanism investigations revealed that the combined FNA pretreatment and SDBS accelerated solubilization, hydrolysis, and acidification steps but inhibited the methanogenesis. All those observations were in agreement with SCFA enhancement.
Collapse
Affiliation(s)
- Jianwei Zhao
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, P.R. China.,Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, P.R. China
| | - Yiwen Liu
- Advanced Water Management Centre, The University of Queensland, QLD 4072, Australia
| | - Bingjie Ni
- Advanced Water Management Centre, The University of Queensland, QLD 4072, Australia
| | - Qilin Wang
- Advanced Water Management Centre, The University of Queensland, QLD 4072, Australia
| | - Dongbo Wang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, P.R. China.,Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, P.R. China.,Advanced Water Management Centre, The University of Queensland, QLD 4072, Australia
| | - Qi Yang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, P.R. China.,Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, P.R. China
| | - Yingjie Sun
- School of Environment and Municipal Engineering, Qingdao Technological University, Qingdao 266033, P.R. China
| | - Guangming Zeng
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, P.R. China.,Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, P.R. China
| | - Xiaoming Li
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, P.R. China.,Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, P.R. China
| |
Collapse
|
47
|
Li X, Zhao J, Wang D, Yang Q, Xu Q, Deng Y, Yang W, Zeng G. An efficient and green pretreatment to stimulate short-chain fatty acids production from waste activated sludge anaerobic fermentation using free nitrous acid. CHEMOSPHERE 2016; 144:160-7. [PMID: 26363316 DOI: 10.1016/j.chemosphere.2015.08.076] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 08/19/2015] [Accepted: 08/28/2015] [Indexed: 05/28/2023]
Abstract
Short-chain fatty acid (SCFA) production from waste activated sludge (WAS) anaerobic fermentation is often limited by the slow hydrolysis rate and poor substrate availability, thus a long fermentation time is required. This paper reports a new pretreatment approach, i.e., using free nitrous acid (FNA) to pretreat sludge, for significantly enhanced SCFA production. Experimental results showed the highest SCFA production occurred at 1.8 mg FNA/L with time of day 6, which was 3.7-fold of the blank at fermentation time of day 12. Mechanism studies revealed that FNA pretreatment accelerated disruption of both extracellular polymeric substances and cell envelope. It was also found that FNA pretreatment benefited hydrolysis and acidification processes but inhibited the activities of methanogens, thereby promoting the yield of SCFA. In addition, the FNA pretreatment substantially stimulated the activities of key enzymes responsible for hydrolysis and acidification, which were consistent with the improvement of solubilization, hydrolysis and acidification of WAS anaerobic fermentation.
Collapse
Affiliation(s)
- Xiaoming Li
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China
| | - Jianwei Zhao
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China
| | - Dongbo Wang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China; Advanced Water Management Centre, The University of Queensland, QLD 4072, Australia.
| | - Qi Yang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China
| | - Qiuxiang Xu
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China
| | - Yongchao Deng
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China
| | - Weiqiang Yang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China
| | - Guangming Zeng
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China
| |
Collapse
|
48
|
Ma B, Wang S, Cao S, Miao Y, Jia F, Du R, Peng Y. Biological nitrogen removal from sewage via anammox: Recent advances. BIORESOURCE TECHNOLOGY 2016; 200:981-990. [PMID: 26586538 DOI: 10.1016/j.biortech.2015.10.074] [Citation(s) in RCA: 358] [Impact Index Per Article: 44.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 10/18/2015] [Accepted: 10/20/2015] [Indexed: 06/05/2023]
Abstract
Biological nitrogen removal from sewage via anammox is a promising and feasible technology to make sewage treatment energy-neutral or energy-positive. Good retention of anammox bacteria is the premise of achieving sewage treatment via anammox. Therefore the anammox metabolism and its factors were critically reviewed so as to form biofilm/granules for retaining anammox bacteria. A stable supply of nitrite for anammox bacteria is a real bottleneck for applying anammox in sewage treatment. Nitritation and partial-denitrification are two promising methods of offering nitrite. As such, the strategies for achieving nitritation in sewage treatment were summarized by reviewing the factors affecting nitrite oxidation bacteria growth. Meanwhile, the methods of achieving partial-denitrification have been developed through understanding the microorganisms related with nitrite accumulation and their factors. Furthermore, two cases of applying anammox in the mainstream sewage treatment plants were documented.
Collapse
Affiliation(s)
- Bin Ma
- Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Shanyun Wang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Shenbin Cao
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Yuanyuan Miao
- Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Fangxu Jia
- Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Rui Du
- Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Yongzhen Peng
- Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
| |
Collapse
|
49
|
Zhou X, Wang Q, Jiang G. Enhancing methane production from waste activated sludge using a novel indigenous iron activated peroxidation pre-treatment process. BIORESOURCE TECHNOLOGY 2015; 182:267-271. [PMID: 25704100 DOI: 10.1016/j.biortech.2015.01.132] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Revised: 01/29/2015] [Accepted: 01/31/2015] [Indexed: 06/04/2023]
Abstract
Methane production from anaerobic digestion of waste activated sludge (WAS) is limited by the slow hydrolysis rate and/or poor methane potential of WAS. This study presents a novel pre-treatment strategy based on indigenous iron (in WAS) activated peroxidation to enhance methane production from WAS. Pre-treatment of WAS for 30 min at 50mg H2O2/g total solids (dry weight) and pH 2.0 (iron concentration in WAS was 7 mg/g TS) substantially enhanced WAS solubilization. Biochemical methane potential tests demonstrated that methane production was improved by 10% at a digestion time of 16d after incorporating the indigenous iron activated peroxidation pre-treatment. Model-based analysis indicated that indigenous iron activated peroxidation pre-treatment improved the methane potential by 13%, whereas the hydrolysis rate was not significantly affected. The economic analysis showed that the proposed pre-treatment method can save the cost by $112,000 per year in a treatment plant with a population equivalent of 300,000.
Collapse
Affiliation(s)
- Xu Zhou
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Qilin Wang
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Queensland 4072, Australia.
| | - Guangming Jiang
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Queensland 4072, Australia
| |
Collapse
|