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Khalil NA, Lajulliadi AF, Abedin FNJ, Fizal ANS, Safie SI, Zulkifli M, Taweepreda W, Hossain MS, Ahmad Yahaya AN. Multifaceted Impact of Lipid Extraction on the Characteristics of Polymer-Based Sewage Sludge towards Sustainable Sludge Management. Polymers (Basel) 2024; 16:2646. [PMID: 39339109 PMCID: PMC11435514 DOI: 10.3390/polym16182646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2024] [Revised: 09/05/2024] [Accepted: 09/12/2024] [Indexed: 09/30/2024] Open
Abstract
Dewatered sludge (DS) is a sewage sludge with a unique property due to extracellular polymeric substances (EPSs) and polymer flocculants. These components form a stable 3D polymer network to increase dewatering efficiency, leaving behind valuable materials such as lipids. This article explored the influences of DS particle size on lipid yield and the effects of extraction on the chemical, morphological, and thermal properties of the residual dewatered sludge (RDS). Lipid yields with unimodal distribution were observed across the particle size ranges (<0.5, 0.5-1.0, 1.0-2.0, 2.0-4.0, and 4.0 mm). The highest lipid yield of 1.95% was extracted from 1.0-2.0 mm after 4 h at 70 °C and 0.1 g/mL sludge-to-solvent ratio. Efficiency was influenced by the DS's morphology, facilitating solvent infiltration and pore diffusion. The extraction process reduced water and organic fractions, resulting in higher thermal stability. Bibliometric analysis of "extraction*" and "sewage sludge" shows increasing research interest from 1973 to 2024. Five research clusters were observed: heavy metal speciation and stabilization, sludge and its bioavailability, extraction techniques and resource recovery, contaminants remediation, as well as phosphorus recovery and agricultural applications. These clusters highlight the diverse approaches to researching DS and RDS while promoting sustainable waste management.
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Affiliation(s)
- Nor Afifah Khalil
- Polymer Science Program, Division of Physical Science, Faculty of Science, Prince of Songkla University, Hat-Yai, Songkla 90110, Thailand;
- Malaysian Institute of Chemical and BioEngineering Technology, Universiti Kuala Lumpur, Alor Gajah 78000, Melaka, Malaysia; (A.F.L.); (F.N.J.A.)
| | - Ahmad Fiqhri Lajulliadi
- Malaysian Institute of Chemical and BioEngineering Technology, Universiti Kuala Lumpur, Alor Gajah 78000, Melaka, Malaysia; (A.F.L.); (F.N.J.A.)
| | - Fatin Najwa Joynal Abedin
- Malaysian Institute of Chemical and BioEngineering Technology, Universiti Kuala Lumpur, Alor Gajah 78000, Melaka, Malaysia; (A.F.L.); (F.N.J.A.)
| | - Ahmad Noor Syimir Fizal
- Centre for Sustainability of Mineral and Resource Recovery Technology (SMaRRT), Universiti Malaysia Pahang Al-Sultan Abdullah, Lebuh Persiaran Tun Khalil Yaakob, Gambang 26300, Pahang, Malaysia;
| | - Sairul Izwan Safie
- Plant Engineering Technology Section, Malaysian Institute of Industrial Technology, Universiti Kuala Lumpur, Masai 81750, Johor, Malaysia;
| | - Muzafar Zulkifli
- Green Chemistry and Sustainability Cluster, Malaysian Institute of Chemical and BioEngineering Technology, Universiti Kuala Lumpur, Alor Gajah 78000, Melaka, Malaysia;
| | - Wirach Taweepreda
- Polymer Science Program, Division of Physical Science, Faculty of Science, Prince of Songkla University, Hat-Yai, Songkla 90110, Thailand;
| | - Md Sohrab Hossain
- HICoE-Centre for Biofuel and Biochemical Research, Institute of Sustainable Energy and Resources, Fundamental and Applied Sciences Department, Universiti Teknologi PETRONAS (UTP), Seri Iskandar 32610, Perak, Malaysia;
| | - Ahmad Naim Ahmad Yahaya
- Green Chemistry and Sustainability Cluster, Malaysian Institute of Chemical and BioEngineering Technology, Universiti Kuala Lumpur, Alor Gajah 78000, Melaka, Malaysia;
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Zhang Q, Zhao Y, Yang Q, Xu B, Zhang X, Xiong H, Zhou H, Xiao R. Quaternization-based graft modification of straw fibers for conditioning the sludge dewatering performance. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2024; 90:287-302. [PMID: 39007320 DOI: 10.2166/wst.2024.225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Accepted: 06/20/2024] [Indexed: 07/16/2024]
Abstract
Extracellular polymeric substances (EPS) are a critical influencing factor in sludge dewatering. Disrupting such EPS contributes to the release of bound water in sludge, enhancing the sludge dewatering performance. In This study, quaternized straw fibers that are destructive to the EPS structure and components in active sludge were prepared useing heterogeneous free radical graft polymerization. Straw fibers, dimethyl diallyl ammonium chloride (DMDAAC), ammonium persulfate (APS), and acrylamide (AM) were taken as the substrate, grafting monomer, catalyst, and cross-linking agent, respectively.The optimal processing conditions determined for the DMDAAC-based quaternization and graft modification of straw fibers were as follows: reaction temperature of 60 °C, reaction time of 5 h, 0.100 g of catalyst APS dosage per gram of straw, and 3.000 ml of DMDAAC dosage per gram of straw. The optimal processing conditions yielded 1.335 g of modified straw fibers per gram of straw, 33.67% grafting rate, and 31.70% substitution of the quaternary ammonium groups. The capillary suction time (CST) was conditioned from 243.3 ± 22.6 s in the original sludge to 134.5 ± 34.45 s. The specific resistance to filtration (SRF) was reduced from 8.82 ± 0.51 × 1012 m/kg in the original sludge to 4.59 ± 0.23 × 1012 m/kg.
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Affiliation(s)
- Qingfang Zhang
- College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou, Gansu 730050, China
| | - Yanbin Zhao
- College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou, Gansu 730050, China; College of Resources & Environment, Jiujiang University, Jiujiang, Jiangxi 332005, China
| | - Qiyong Yang
- College of Resources & Environment, Jiujiang University, Jiujiang, Jiangxi 332005, China; Key Laboratory of Watershed Ecological Process and Information of Jiangxi Province, Jiujiang, Jiangxi 332005, China E-mail:
| | - Binjie Xu
- College of Resources & Environment, Jiujiang University, Jiujiang, Jiangxi 332005, China; Key Laboratory of Watershed Ecological Process and Information of Jiangxi Province, Jiujiang, Jiangxi 332005, China
| | - Xinhua Zhang
- College of Resources & Environment, Jiujiang University, Jiujiang, Jiangxi 332005, China; Key Laboratory of Watershed Ecological Process and Information of Jiangxi Province, Jiujiang, Jiangxi 332005, China
| | - Houfeng Xiong
- College of Resources & Environment, Jiujiang University, Jiujiang, Jiangxi 332005, China; Key Laboratory of Watershed Ecological Process and Information of Jiangxi Province, Jiujiang, Jiangxi 332005, China
| | - Han Zhou
- College of Resources & Environment, Jiujiang University, Jiujiang, Jiangxi 332005, China
| | - Ruimin Xiao
- College of Resources & Environment, Jiujiang University, Jiujiang, Jiangxi 332005, China
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3
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Wu Y, Liu Y, Zhang X, Gao M, Zhang C, Zang X, Wu L. Feasibility of sludge deep dewaterability improvement for incineration disposal by combined conditioning of freeze-thaw and sawdust. ENVIRONMENTAL RESEARCH 2024; 252:118987. [PMID: 38670212 DOI: 10.1016/j.envres.2024.118987] [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: 02/01/2024] [Revised: 03/22/2024] [Accepted: 04/21/2024] [Indexed: 04/28/2024]
Abstract
Sludge incineration is the main strategy for sludge reduction in China. The combined conditioning of lime and chemical agents has been proven to achieve sludge dewatering by disrupting the extracellular polymeric substances (EPS) of sludge and reducing its compressibility. However, when incineration is the intended disposal purpose, this method poses challenges such as incomplete combustion, equipment corrosion, secondary pollution, and decreased calorific value of sludge cake. In contrast, freeze-thaw conditioning, coupled with sawdust as a high-calorific-value bio-waste, emerges as an efficient and clean alternative. The research investigates the synergistic effects of freeze-thaw and sawdust co-conditioning on various sludge properties, including dewaterability, compressibility, consolidation, permeability, microscopicity, and calorific value. The study reveals that the combined conditioning significantly reduces water content and compressibility while increasing void ratio, consolidation, permeability, and enhancing the calorific value of the sludge cake. Specifically, sludge cake conditioned with 60% dried solids (DS) sawdust and freeze-thaw achieved a water content (Wc) of 49.07% and a calorific value of 1422.3 kcal/kg, meeting standards for self-sustained incineration. With heat recovery, the combined conditioning generates an economic revenue of 25.1 $/t DS after deducting costs, thereby reducing the overall cost of sludge reduction treatment. This research offers a clean and practical solution for sludge incineration and reduction, demonstrating great economic value and application potential.
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Affiliation(s)
- Yajun Wu
- Department of Civil Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, PR China.
| | - Yang Liu
- Department of Civil Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, PR China.
| | - Xudong Zhang
- Department of Civil Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, PR China.
| | - Mengze Gao
- Department of Civil Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, PR China
| | - Changsong Zhang
- Shanghai Yaxin Urban Construction Co., Ltd., Shanghai, PR China
| | - Xueke Zang
- Shanghai Yaxin Urban Construction Co., Ltd., Shanghai, PR China
| | - Linbao Wu
- Department of Civil Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, PR China
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Liu Z, Luo F, He L, Wang S, Wu Y, Chen Z. Physical conditioning methods for sludge deep dewatering: A critical review. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 360:121207. [PMID: 38788408 DOI: 10.1016/j.jenvman.2024.121207] [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: 01/22/2024] [Revised: 04/17/2024] [Accepted: 05/18/2024] [Indexed: 05/26/2024]
Abstract
Sludge is an inevitable waste product of sewage treatment with a high water content and large volume, it poses a significant threat of secondary pollution to both water and the atmosphere without proper disposal. In this regard, dewatering has emerged as an attractive method in sludge treatment, as it can reduce the sludge volume, enhance its transportability and calorific value, and even decrease the production of landfill leachate. In recent years, physical conditioning methods including non-chemical conditioners or energy input alone, have been extensively researched for their potential to enhance sludge dewatering efficiency, such as thermal treatment, freeze-thaw, microwave, ultrasonic, skeleton builders addition, and electro-dewatering, as well as combined methods. The main objective of this paper is to comprehensively evaluate the dewatering capacity of various physical conditioning methods, and identify key factors affecting sludge dewatering efficiency. In addition, future research anticipated directions and outlooks are proposed. This work is expected to provide valuable insights for developing efficient, eco-friendly, and low-energy consumption techniques for deep sludge dewatering.
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Affiliation(s)
- Zhuo Liu
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Material Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Fang Luo
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Material Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Lingzhi He
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Material Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Siqi Wang
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Material Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Yi Wu
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Material Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Zhuqi Chen
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Material Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
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5
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Xiao K, Lv Y, Yu W, Yang J. Visualization of water transfer channel in sludge dewatering conditioned with skeleton builders by X-ray micro-computed tomography. CHEMOSPHERE 2024; 355:141818. [PMID: 38548085 DOI: 10.1016/j.chemosphere.2024.141818] [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: 01/07/2024] [Revised: 03/05/2024] [Accepted: 03/25/2024] [Indexed: 04/18/2024]
Abstract
Skeleton builders were normally deemed to improve the high porosity and newly-generated permeability of sludge cakes by building water transfer channel during high pressure filtration, thus enhancing sludge dewaterability. However, currently a direct visualization proof of water transfer channel was still lacking. This study provided the direct proof for visualizing water transfer channel in dewatered sludge cakes conditioned with a typical skeleton builder (i.e., phosphogypsum (PG)) by X-ray micro-computed tomography (micro-CT) for the first time. After the addition of PG, the pixel value and image luminance increased significantly, indicating the presence of high density substances from both two-dimensional (2D) cross section and three-dimensional (3D) reconstruction CT images. Moreover, the CT numbers showed strong and negative correlations with specific resistance to filtration (SRF) (R = - 0.99, p < 0.05), capillary suction time (CST) (regression coefficient (R) = - 0.87, probability (p) < 0.05), and water content of the dewatered sludge cake (R = - 0.99, p < 0.05), respectively. These results indicated that the X-ray micro-CT could be a potential technique for analyzing the water distribution in sludge samples conditioned with skeleton builders.
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Affiliation(s)
- Keke Xiao
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, Hubei, 430074, China; Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, 1037 Luoyu Road, Wuhan, Hubei, 430074, China; Environmental Science and Engineering Program, Guangdong Technion-Israel Institute of Technology, 241 Daxue Road, Shantou, Guangdong, 515063, China
| | - Yang Lv
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, Hubei, 430074, China; Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment of the People's Republic of China, 8 Jiangwangmiao Street, Nanjing, Jiang Su, 210042, China
| | - Wenbo Yu
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, Hubei, 430074, China; Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, 1037 Luoyu Road, Wuhan, Hubei, 430074, China
| | - Jiakuan Yang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, Hubei, 430074, China; Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, 1037 Luoyu Road, Wuhan, Hubei, 430074, China; Hubei Water Quality Safety and Water Pollution Control Engineering Center, 1037 Luoyu Road, Wuhan, Hubei, 430074, China; State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, Hubei, 430074, China.
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6
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Hu H, Liu H, Xiao H, Jin M, Huang Z, Yao H. Assisting role of carbonaceous skeleton in sludge thermal hydrolysis and press filtration. CHEMOSPHERE 2024; 352:141501. [PMID: 38401864 DOI: 10.1016/j.chemosphere.2024.141501] [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: 12/13/2023] [Revised: 02/01/2024] [Accepted: 02/17/2024] [Indexed: 02/26/2024]
Abstract
As a key step in disposal and reutilization, sludge dewatering is very difficult, since extracellular polymers substances (EPS) binds the water, and compressible organic matter deforms and causes water filtration channels to collapse. Sludge dewaterability was demonstrated to enhance by carbonaceous skeleton (CSkel)-assisted thermal hydrolysis in our previously study. This work further investigated the assisting role of different types of CSkel in EPS decomposition during sludge thermal hydrolysis stage and channels reformation during press filtration stage. Two major types of CSkel, lignocellulosic waste (waste sawdust, waste straw, processing by-product) and protein-rich waste (shrimp shells, jatropha oil cake), were selected. The experimental results showed that in the thermal hydrolysis stage, the decomposition of lignocellulosic waste would increase fatty acids production by 28%, resulting in an acidic environment that reduced the total amount of three hydrophilic amino acids, i.e., glycine, serine and threonine. These promoted the release of water from the sludge. In the press filtration stage, average pore size of sludge was reduced by approximately 87% and nanoscale holes began to appear and increase. Assisting of CSkel rebuilt the filtration channels which brought good connectivity between the pores in sludge cake. Lignocellulosic waste proved significantly more effective than protein-rich waste in achieving a water removal rate of 88.63% under 1 MPa. This study provided a basis for selecting suitable CSkel to optimize sludge dewatering for subsequent utilization.
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Affiliation(s)
- Hang Hu
- School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Huan Liu
- School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.
| | - Han Xiao
- School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Minghao Jin
- School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Zhaowei Huang
- Wuhan Tianyuan Environmental Protection Co., Ltd, Wuhan, 430014, China
| | - Hong Yao
- School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
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7
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Ajmal M, Shao Y, Huo W, Lu W. Deep-dewatering of sewage sludge using double dielectric barrier discharge (DDBD) plasma technology. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:168887. [PMID: 38016553 DOI: 10.1016/j.scitotenv.2023.168887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 11/12/2023] [Accepted: 11/23/2023] [Indexed: 11/30/2023]
Abstract
Deep dewatering of sewage sludge is essential for optimizing disposal and resource recovery. This study explores the potential of Double Dielectric Barrier Discharge (DDBD) plasma for enhancing waste activated sludge (WAS) dewatering. Key operational parameters (applied voltage, treatment duration, and air feeding rate) were systematically investigated using a two-step approach: Single Factor-at-a-Time (SFAT) and central composite design (CCD) within the response surface methodology (RSM) framework. The aim was to identify influential factors and their optimal settings for maximizing dewatering efficiency while minimizing energy usage. Higher applied voltages (30 kV) and longer treatment durations (40 min) notably improved % moisture reduction (%MR) (92.92 % and 94.35 %, respectively). ANOVA analysis emphasized the equal and substantial impact of applied voltage and treatment duration on %MR and energy efficiency (EE), whereas the air feeding rate exhibited no significant effect. However, it's worth noting that %MR and EE did not display a strictly linear relationship, suggesting complex interactions. Furthermore, two soft sensing models were developed: a quadratic model for %MR and a linear model for energy efficiency (EE). Results showed minimal reductions in TOC content, maintaining values between 13.68 % and 14.28 % compared to untreated sludge 14.37 %. The study also revealed that ROS generated by DDBD plasma played a key role in sludge disintegration, as observed through SEM and FTIR, enhancing dewatering efficiency by the destruction of sludge flocs and the transformation of organic substances. In conclusion, DDBD plasma technology offers a sustainable solution for effective sludge dewatering in WWTPs, preserving organic content.
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Affiliation(s)
- Muhammad Ajmal
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Yuchao Shao
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Weizhong Huo
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Wenjing Lu
- School of Environment, Tsinghua University, Beijing 100084, China.
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8
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Zhang Y, Pei J, Zheng S, Li Y, Lv N, Ma L. Enhanced dewaterability of sludge by Fe(II)-sludge biochar activate persulfate. ENVIRONMENTAL TECHNOLOGY 2024; 45:854-866. [PMID: 36161866 DOI: 10.1080/09593330.2022.2129457] [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: 05/14/2022] [Accepted: 09/17/2022] [Indexed: 06/16/2023]
Abstract
Sludge biochar supported Fe(II) (Fe(II)-SBC) was successfully prepared using waste activated sludge as peroxydisulfate (PDS) activator to condition sludge for deep dewatering. The experimental results showed that Fe(II)-SBC with FeO on it could effectively active PDS to produce SO 4 - ⋅ and HO ⋅ . The radicals could destroy the structure of sludge cells and extracellular polymeric substance (EPS), transformed the hydrophilic and tightly bound EPS into soluble-EPS, degrade partial proteins and polysaccharides and released bound water. The negatively charged groups on sludge floc were dripped off by SO 4 - ⋅ /HO ⋅ or neutralized with Fe2+, Fe3+, H+, or Fe(II)-SBC, leading to an increase in zeta potential to -2.24 mV and sludge destabilization. The residual Fe(II)-SBC served as a skeleton builder that decreased the compression coefficient of the sludge cake to 0.75. Under the combined functions, the CST and SRF were reduced by 70% and 82.7%, respectively, and Wc was reduced to 72.4%. The byproducts of Fe3+ and SO42- finally remained in sludge cake in the form of NaFeSi2O6 and CaSO4.
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Affiliation(s)
- Yanping Zhang
- School of Civil Engineering and Transportation, Hebei University of Technology, Tianjin, People's Republic of China
| | - Jiahua Pei
- School of Civil Engineering and Transportation, Hebei University of Technology, Tianjin, People's Republic of China
| | - Songchao Zheng
- School of Civil Engineering and Transportation, Hebei University of Technology, Tianjin, People's Republic of China
| | - Yibing Li
- School of Civil Engineering and Transportation, Hebei University of Technology, Tianjin, People's Republic of China
| | - Ning Lv
- School of Civil Engineering and Transportation, Hebei University of Technology, Tianjin, People's Republic of China
| | - Liran Ma
- School of Civil Engineering and Transportation, Hebei University of Technology, Tianjin, People's Republic of China
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Bao P, Du C, Li Y, Jiang H, Zhou L, Yu G, Sun S, Zhou L, Li X, Teng J, Wang X, Wang J. Application of skeleton builders to sludge dewatering and disposal: A critical review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167106. [PMID: 37717769 DOI: 10.1016/j.scitotenv.2023.167106] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 09/13/2023] [Accepted: 09/13/2023] [Indexed: 09/19/2023]
Abstract
With the development of cities and population, the production of sludge is increasing annually. It has become an unavoidable challenge to achieve sludge dewatering and disposal by a cost-effective, efficient and safe process. In this work, firstly, the factors limiting sludge dewatering are reviewed in terms of moisture distribution, sludge concentration, organic matter content, electronegativity, floc strength, and extracellular polymers (EPS). Subsequently, focusing on the dewatering technology about the skeleton builder, the recent progress of it is detailed in terms of mechanism, evaluation indicators, influencing factors, and technology coupling. In addition, the impact of skeleton builders on the sludge disposal stage is concluded. Finally, the challenges faced by sludge dewatering and skeleton builders are prospected. This review will provide some theoretical basis and technical guidance for subsequent experiments and practices regarding skeleton builders.
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Affiliation(s)
- Purui Bao
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China
| | - Chunyan Du
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China; Engineering Technology Research Center of Hunan Dongting Lake Flood Control and Water Resources Protection of Hunan Province, Hunan Water Resources and Hydropower Survey, Design, Planning and Research Co., Ltd, Changsha 410007, China; Engineering and Technical Center of Hunan Provincial Environmental Protection for River Lake Dredging Pollution Control, Changsha 410114, China.
| | - Yifu Li
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China; Engineering and Technical Center of Hunan Provincial Environmental Protection for River Lake Dredging Pollution Control, Changsha 410114, China.
| | - Heng Jiang
- Engineering Technology Research Center of Hunan Dongting Lake Flood Control and Water Resources Protection of Hunan Province, Hunan Water Resources and Hydropower Survey, Design, Planning and Research Co., Ltd, Changsha 410007, China
| | - Lu Zhou
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China; Engineering and Technical Center of Hunan Provincial Environmental Protection for River Lake Dredging Pollution Control, Changsha 410114, China
| | - Guanlong Yu
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China; Engineering and Technical Center of Hunan Provincial Environmental Protection for River Lake Dredging Pollution Control, Changsha 410114, China
| | - Shiquan Sun
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China; Engineering and Technical Center of Hunan Provincial Environmental Protection for River Lake Dredging Pollution Control, Changsha 410114, China
| | - Lean Zhou
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China; Engineering and Technical Center of Hunan Provincial Environmental Protection for River Lake Dredging Pollution Control, Changsha 410114, China
| | - Xue Li
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China
| | - Junyi Teng
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China
| | - Xiaowen Wang
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China
| | - Junchao Wang
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China
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10
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Zhang Y, Liu J, Bao Y, Liu P, Wei J, Li X, Wang Q, Ge Z. Application of coffee ground-based skeleton builder with FeCl 3 for conditions of pre-dewatered sludge toward further deep dewatering. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023:10.1007/s11356-023-29325-8. [PMID: 37608176 DOI: 10.1007/s11356-023-29325-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 08/09/2023] [Indexed: 08/24/2023]
Abstract
Skeleton builders are essential for achieving deep sludge dewatering. In this study, a novel spent coffee ground (SCG)-based skeleton builder was developed to attain deep sludge dewatering by combined conditioning with FeCl3, and possible mechanisms were examined. Through different surface analysis techniques, it was demonstrated that at a pyrolysis temperature of 300 °C, the spent coffee ground biochar (SCGB-300) has an intact pore structure, a rigid carbon skeleton, and large oxygen-containing functional groups, making it the best skeleton builder for sludge dewatering. When combined with FeCl3 for conditioning, the structure of SCGB-300 remained intact under high pressure and played important role. The rich porous structure facilitated water drainage. During the sludge conditioning, small amount of positive charge on the surface of SCGB-300 further increased the zeta potential of sludge through charge neutralization. At the same time, the adsorption of SCGB-300 removed viscous hydrophilic substances and further improved the dewatering performance. At an optimum dosage of 6% (dry solid, DS) FeCl3 and 30% SCGB-300 (DS), the moisture content of sludge was reduced from 85.47% to 63.35%, and the dewatering rate was increased from 46.08% to 70.03%. Therefore, SCGB is a promising skeleton builder for sludge conditioning and deep dewatering.
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Affiliation(s)
- Yixin Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology|, Beijing, 100124, China
| | - Jibao Liu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
- Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Yunfan Bao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology|, Beijing, 100124, China
| | - Pengyu Liu
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology|, Beijing, 100124, China
| | - Jinyi Wei
- Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Xueyi Li
- Beijing Capital Sludge Disposal Co. Ltd., Beijing, 100044, China
| | - Qiao Wang
- Beijing Capital Sludge Disposal Co. Ltd., Beijing, 100044, China
| | - Zheng Ge
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology|, Beijing, 100124, China.
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11
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Xia T, Zhang X, Chen D, Gao Z, Ji Y, Xia J, Wang L. Effects of ceramsite derived from sewage sludge combined with the O 3-FeCl 3/PAM process on the dewatering of waste-activated sludge and investigation of dewatering mechanisms. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2023; 88:367-380. [PMID: 37522439 PMCID: wst_2023_224 DOI: 10.2166/wst.2023.224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/01/2023]
Abstract
The high water content of waste-activated sludge restricts the subsequent disposal of sludge. The dehydration properties of O3, ferric chloride (FeCl3)/polyacrylamide, and sludge ceramsite sand (SCS) were studied. Simultaneously, the effect of combining the three was investigated to support the deep dehydration of waste-activated sludge. Experimental results showed that with13.42 mg/(g dry solids (DS)) of O3, 109.89 mg/(g DS) of FeCl3, and 100 mesh dosage of 70% DS of sludge ceramsite on weight, the highest sludge net yield was 7.13 kg/(m2·h) and the minimum specific resistance to filtration of sludge cake was 1.02 × 1012 (m/kg). Compared with the compressibility of the raw sludge, the compressibility of the sludge cake decreased by 37.48%. Moreover, the YN (net yield) increased by 73.55%. The results demonstrate that the structure of cracking, flocculation, and hydrophobic framework is the mechanism of sludge dewatering in this combined process. This combined treatment process provides a new perspective for the realization of deep dewatering of sludge and is anticipated to be a successful sludge dehydration method.
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Affiliation(s)
- Ting Xia
- College of Urban Construction, Nanjing Tech University, Puzhu Road 30, Nanjing 211816, China E-mail:
| | - Xu Zhang
- College of Urban Construction, Nanjing Tech University, Puzhu Road 30, Nanjing 211816, China
| | - Dongjie Chen
- College of Urban Construction, Nanjing Tech University, Puzhu Road 30, Nanjing 211816, China
| | - Zaizhuang Gao
- College of Urban Construction, Nanjing Tech University, Puzhu Road 30, Nanjing 211816, China
| | - Yuxiao Ji
- College of Urban Construction, Nanjing Tech University, Puzhu Road 30, Nanjing 211816, China
| | - Jianjun Xia
- College of Urban Construction, Nanjing Tech University, Puzhu Road 30, Nanjing 211816, China
| | - Lei Wang
- Anhui Academy of Environmental Science Research, Hefei 230071, China
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12
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Feng G, Tian Z, Wang J. Effects of rice husk powder and thermal hydrolysis on sludge characteristics. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2023; 87:2315-2327. [PMID: 37186633 PMCID: wst_2023_131 DOI: 10.2166/wst.2023.131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
To reduce the water content and improve the incineration characteristics of sludge, rice husk and thermal hydrolysis were employed in this study. Effects of rice husk and thermal hydrolysis on the characteristics of the sludge were investigated. The results showed that synergistic thermal hydrolysis with rice husk could effectively destroy sludge particles and release more bound water. For rice husk with a particle size of 50-mesh and an additional amount of rice husk at 1:0.2, the solid content of the sludge was reduced from 17.4 to 16.2%, and the sludge particle size was reduced by 6%. Filtration time and specific resistance to filtrate (SRF) were shortened by 88.9 and 98.7%, respectively. The organic matter content of the filtration cake increased by 14%, compared with the sludge treated by thermal hydrolysis without rice husk. Furthermore, it could be shown that the most optimal conditions were rice husk of particle size 50-mesh and an additional amount of rice husk at 1:0.2, which could lead to effective thermal hydrolysis and higher organic matter content of the filtration cake.
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Affiliation(s)
- Guohong Feng
- School of Environment & Resource, Taiyuan University of Science & Technology, Taiyuan 030024, China E-mail:
| | - Ziyang Tian
- School of Environment & Resource, Taiyuan University of Science & Technology, Taiyuan 030024, China E-mail:
| | - Jun Wang
- School of Environment & Resource, Taiyuan University of Science & Technology, Taiyuan 030024, China E-mail:
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13
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Xing J, Tang Q, Gan M, Ji Z, Fan X, Sun Z, Chen X. Co-treatment of municipal solid waste incineration fly ash (MSWI FA) and municipal sludge: A innovative method to improve sludge dewatering with fly ash dechlorination. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 332:117403. [PMID: 36738722 DOI: 10.1016/j.jenvman.2023.117403] [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: 12/10/2022] [Revised: 01/16/2023] [Accepted: 01/27/2023] [Indexed: 06/18/2023]
Abstract
The complexity of municipal sludge dewatering is a bottleneck problem limiting resource utilization. In this paper, adding municipal solid waste incineration fly ash (MSWI FA) to municipal sludge for enhanced dewatering was applied, while the chlorine salt in MSWI FA was simultaneously removed using water in municipal sludge. The effects of different dosages and chemical components of MSWI FA on municipal sludge dewatering, and the removal effect of municipal sludge washing on Cl element were investigated. The results showed that the municipal sludge's specific resistance to filtration after co-treatment was significantly reduced, and more hydrophobic channels were formed in the vacuum suction filtration of the treated municipal sludge, conducive to efficient water removal. The moisture content of municipal sludge was reduced from 96.0% to 48.3%, and the moisture reduction rate increased from 17.7% to 32.1%. The chemical composition of MSWI FA could effectively promote the dewatering of municipal sludge, among which CaO was the best, followed by CaCl2 and NaCl, and KCl was the worst. Simultaneously, the municipal sludge showed a good effect on removing Cl from MSWI FA. The minimum Cl content in the mixture after Co-treatment is 1.5%. These results could provide a new way to dispose of MSWI FA and municipal sludge.
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Affiliation(s)
- Jinxin Xing
- School of Minerals Processing & Bioengineering, Central South University, Changsha, 410083, PR China
| | - Qingyu Tang
- School of Minerals Processing & Bioengineering, Central South University, Changsha, 410083, PR China
| | - Min Gan
- School of Minerals Processing & Bioengineering, Central South University, Changsha, 410083, PR China.
| | - Zhiyun Ji
- School of Minerals Processing & Bioengineering, Central South University, Changsha, 410083, PR China
| | - Xiaohui Fan
- School of Minerals Processing & Bioengineering, Central South University, Changsha, 410083, PR China
| | - Zengqing Sun
- School of Minerals Processing & Bioengineering, Central South University, Changsha, 410083, PR China
| | - Xuling Chen
- School of Minerals Processing & Bioengineering, Central South University, Changsha, 410083, PR China
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14
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Chen C, Zhang T, Lv L, Chen Y, Tang W, Tang S. A novel insight on the intensification mechanism of sludge dewaterability by ionic liquids. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 331:117291. [PMID: 36657200 DOI: 10.1016/j.jenvman.2023.117291] [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: 10/04/2022] [Revised: 01/01/2023] [Accepted: 01/10/2023] [Indexed: 06/17/2023]
Abstract
The huge output of sewage sludge has caused a remarkable environmental burden. Sludge dewatering is considered as an important way to reduce the sludge volume. Five imidazole-based ionic liquids were used to improve the dewaterability of sewage sludge. 1-ethyl-3-methylimidazolium dihydrogen phosphate ([Emim][H2PO4]) was screened out as a potential conditioner of sludge due to its excellent dewatering performance and reusability. The solid content of sludge filter cake after treatment with [Emim][H2PO4] was about 10% higher than that of sludge treated by cationic polyacrylamides (CPAM). The intensification mechanism of ionic liquids to the improvement of sludge dewatering performance was studied. The presence of acidic ionic liquids [Emim][H2PO4] resulted the increase of zeta potential from -14.57 ± 0.81 mV to -5.60 ± 0.30 mV and led to the protonation of biopolymers. Acidic ionic liquids [Emim][H2PO4] inactivated the microorganism and led to a porous and unconsolidated structure of the solid sludge particles. All these effects were conducive to destroy the microstructure of sludge and release water. However, [Emim]Cl, [Bmim][OTf] and [Hmim][OTf] showed little effect on the protonation of ionizable functional groups at near-neutral environment. The dissolution of biopolymer decreased the zeta potential and strengthened the electrostatic repulsion. So, they showed weaker intensification effects than CPAM.
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Affiliation(s)
- Changtao Chen
- Sichuan Base of International Science and Technology Cooperation for Green Chemical Industry, School of Chemical Engineering, Sichuan University, Chengdu, 610065, China.
| | - Tao Zhang
- Sichuan Base of International Science and Technology Cooperation for Green Chemical Industry, School of Chemical Engineering, Sichuan University, Chengdu, 610065, China.
| | - Li Lv
- Sichuan Base of International Science and Technology Cooperation for Green Chemical Industry, School of Chemical Engineering, Sichuan University, Chengdu, 610065, China.
| | - Yanxiao Chen
- Sichuan Base of International Science and Technology Cooperation for Green Chemical Industry, School of Chemical Engineering, Sichuan University, Chengdu, 610065, China.
| | - Wenxiang Tang
- Sichuan Base of International Science and Technology Cooperation for Green Chemical Industry, School of Chemical Engineering, Sichuan University, Chengdu, 610065, China.
| | - Shengwei Tang
- Sichuan Base of International Science and Technology Cooperation for Green Chemical Industry, School of Chemical Engineering, Sichuan University, Chengdu, 610065, China.
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15
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Yang Z, Liu S, Tang Y, Zhou Y, Xiao L. Enhancement of excess sludge dewatering by three-dimensional electro-Fenton process based on sludge biochar. JOURNAL OF HAZARDOUS MATERIALS 2023; 445:130438. [PMID: 36446313 DOI: 10.1016/j.jhazmat.2022.130438] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 11/10/2022] [Accepted: 11/17/2022] [Indexed: 06/16/2023]
Abstract
Deep dewatering of waste activated sludge (WAS) is still a challenge due to high content of bound water and non-Newton fluid properties of sludge flocs. Electro-Fenton (EF) can enhance sludge dewaterability, however, low pH needed in homogeneous EF and fine flocs after EF conditioning influenced deep dewatering of sludge and the subsequent resource recovery disposal. In this study, a three dimension electro-Fenton (3D-EF) using Fe modified sludge biochar (Fe@SBC) as particle electrode, heterogeneous Fenton catalyst and skeleton builder for deep dewatering of sludge under neutral pH was proposed. Fe@SBC obtained at 800 °C exhibited high capacity of H2O2 electrogeneration and activation due to high conductivity and content of 2e-ORR selectivity functional groups. With promoted generation of H2O2 and hydroxyl radical (•OH), 3D-EF with Fe@SBC showed higher decomposition of bound extracellular polymeric substances (EPS) and disintegration of cells in sludge flocs, resulting in releasing bound and intracellular water into free water. Compared with EF, 3D-EF with Fe@SBC800 had higher ability in breaking macromolecules of protein and polysaccharide, as well as removing -COOH and -NH2 groups in EPS, which could facilitate release of bound water trapped in EPS and self-coagulation of fine flocs. During subsequent filtering process, Fe@SBC could enhance sludge filterability as skeleton builder. A synergetic effect of strong oxidation and physical conditioning were proposed in 3D-EF sludge dewaterability with Fe@SBC, and the improved oxidation by Fe@SBC was supposed to play the major role.
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Affiliation(s)
- Zongcai Yang
- School of the Environment, State Key Laboratory for Pollution Control and Resource Reuse, Nanjing University Xianlin Campus, Nanjing 210023, China
| | - Shulei Liu
- School of the Environment, State Key Laboratory for Pollution Control and Resource Reuse, Nanjing University Xianlin Campus, Nanjing 210023, China
| | - Yuqiong Tang
- School of the Environment, State Key Laboratory for Pollution Control and Resource Reuse, Nanjing University Xianlin Campus, Nanjing 210023, China
| | - Yingping Zhou
- School of the Environment, State Key Laboratory for Pollution Control and Resource Reuse, Nanjing University Xianlin Campus, Nanjing 210023, China
| | - Lin Xiao
- School of the Environment, State Key Laboratory for Pollution Control and Resource Reuse, Nanjing University Xianlin Campus, Nanjing 210023, China.
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16
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Feasibility of improving wastewater sludge dewaterability by combination of cationic polyacrylamide and synthetic fibers for resource utilization. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.122620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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17
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Yu H, Zhang D, Gu L, Wen H, Zhu N. Coupling sludge-based biochar and electrolysis for conditioning and dewatering of sewage sludge: Effect of char properties. ENVIRONMENTAL RESEARCH 2022; 214:113974. [PMID: 35952734 DOI: 10.1016/j.envres.2022.113974] [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: 06/03/2022] [Revised: 07/07/2022] [Accepted: 07/20/2022] [Indexed: 06/15/2023]
Abstract
The addition of sludge-based biochar during electrochemical pretreatment of sewage sludge, as an efficient hybrid technology, is potentially to be applied in sludge deep-dewatering. The chars functioned as conductors, catalysts and skeleton particles could enhance the sludge dewaterability and increase the calorific value of the dewatered sludge cake. However, the effect of synthesis conditions on the char properties and further on the dewatering performance is still unknown. Herein, the sludge-based particle electrodes (SPEs) under three main synthesis conditions, including liquid-solid ratio, pyrolysis temperature and time, were prepared. The sludge-based biochars (i.e., SPE-400, SPE-600, and SPE-800 pyrolyzed under 400, 600 and 800 °C, respectively) were characterized and utilized as three-dimensional electrodes during sludge electrolysis. The increased pyrolysis temperature (within 400-800 °C) resulted in the enrichment of metallic ions and increment of specific surface area and pore volume of SPE, which led to the increased catalysis and adsorption sites for viscous proteins (PNs). Particularly, the pores of SPE-800 provided more drainage channels as skeleton builders. Compared with raw sludge, the capillary suction time (CST) and the specific resistance of filtration (SRF) of the treated sludge with 3D-SPE-800 were reduced by 58.12% and 81.01%, respectively, but the net sludge solids yield (YN) was increased by 87.05%. The highest decrease of hydrophilic α-Helix content in PNs (from 9.93% to 7.30%) was observed when using SPE-800 as particle electrode, revealing the crucial role of char characteristics on protein reduction and subsequent dewatering enhancement. The synergistic effects of electrolysis and sludge-based biochar provided a new insight for a closed-loop pretreatment of sewage sludge in the wastewater treatment plant.
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Affiliation(s)
- Haixiang Yu
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200093, PR China
| | - Daofang Zhang
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200093, PR China
| | - Lin Gu
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200093, PR China; School of Environment Engineering, Shanghai Jiao Tong University, Shanghai, 200240, PR China.
| | - Haifeng Wen
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200093, PR China
| | - Nanwen Zhu
- School of Environment Engineering, Shanghai Jiao Tong University, Shanghai, 200240, PR China
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18
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Kocbek E, Garcia HA, Hooijmans CM, Mijatović I, Kržišnik D, Humar M, Brdjanovic D. Effects of the sludge physical-chemical properties on its microwave drying performance. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 828:154142. [PMID: 35227715 DOI: 10.1016/j.scitotenv.2022.154142] [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: 10/05/2021] [Revised: 01/31/2022] [Accepted: 02/21/2022] [Indexed: 06/14/2023]
Abstract
Thermal drying is an effective sludge treatment method for dealing with large volumes of sludge. Microwave (MW) technology has been proposed as an effective and efficient technology for sludge drying. The physical-chemical properties of the sludge depend both on the origin of the sludge, as well as on the treatment process at which the sludge has been exposed. The physical-chemical properties of the sludge affect the performance and the subsequent valorisation and management of the sludge. This study evaluated the effect of certain physical-chemical properties of the sludge (moisture content, organic content, calorific value, porosity, hydrophobicity, and water-sludge molecular interaction, among others) on the MW sludge drying and energy performance. Four different types of sludge were evaluated collected from municipal wastewater treatment plants and septic tanks. The performance of the MW system was assessed by evaluating the sludge drying rates, exposure times, energy efficiencies and power input consumed by the MW system and linking the MW drying performance to the sludge physical-chemical properties. The results confirmed that MW drying substantially extends the constant drying period associated with unbound water evaporation, irrespective of the sludge sample evaluated. However, the duration and intensity were determined to depend on the dielectric properties of the sludge, particularly on the distribution of bound and free water. Sludge samples with a higher amount of free and loosely bound water absorbed and converted MW energy into heat more efficiently than sludge samples with a lower amount of free water. As a result, the sludge drying rates increased and the constant drying rate period prolonged; hence, leading to an increase in MW drying energy efficiency. The availability of free and loosely bound water molecules was favoured when hydrophobic compounds, e.g., oils and fats, were present in the sludge.
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Affiliation(s)
- Eva Kocbek
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, the Netherlands; Department of Water Supply, Sanitation and Environmental Engineering, IHE-Delft Institute for Water Education, Westvest 7, 2611 AX Delft, the Netherlands; Tehnobiro d.o.o., Heroja Nandeta 37, 2000 Maribor, Slovenia.
| | - Hector A Garcia
- Department of Water Supply, Sanitation and Environmental Engineering, IHE-Delft Institute for Water Education, Westvest 7, 2611 AX Delft, the Netherlands
| | - Christine M Hooijmans
- Department of Water Supply, Sanitation and Environmental Engineering, IHE-Delft Institute for Water Education, Westvest 7, 2611 AX Delft, the Netherlands
| | - Ivan Mijatović
- Tehnobiro d.o.o., Heroja Nandeta 37, 2000 Maribor, Slovenia
| | - Davor Kržišnik
- Department of Wood Science and Technology, Biotechnical Faculty, University of Ljubljana Jamnikarjeva 101, SI-1000 Ljubljana, Slovenia
| | - Miha Humar
- Department of Wood Science and Technology, Biotechnical Faculty, University of Ljubljana Jamnikarjeva 101, SI-1000 Ljubljana, Slovenia
| | - Damir Brdjanovic
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, the Netherlands; Department of Water Supply, Sanitation and Environmental Engineering, IHE-Delft Institute for Water Education, Westvest 7, 2611 AX Delft, the Netherlands
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19
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Yang Y, Yang X, Wang X, Yang Q, Xu W, Li Y. Explore the closed-loop disposal route of surplus sludge: Sludge self-circulation preparation of sludge-based biochar (SBB) to enhance sludge dewaterability. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.128304] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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20
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Wang X, Shen Y, Liu X, Ma T, Wu J, Qi G. Fly ash and H 2O 2 assisted hydrothermal carbonization for improving the nitrogen and sulfur removal from sewage sludge. CHEMOSPHERE 2022; 290:133209. [PMID: 34896175 DOI: 10.1016/j.chemosphere.2021.133209] [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: 09/25/2021] [Revised: 12/02/2021] [Accepted: 12/06/2021] [Indexed: 06/14/2023]
Abstract
In this study, fly ash and hydrogen peroxide (H2O2) assisted hydrothermal carbonization (HTC) was used to improve the removal efficiency of nitrogen (N) and sulfur (S) from sewage sludge (SS). The removal rate and distribution of N and S in hydrochar were evaluated, and properties of the aqueous phase were analyzed to illustrate the N and S transformation mechanism during fly ash and H2O2 assisted HTC treatment of SS. The results suggested that during HTC process assisted by fly ash (10% of raw SS), dehydration, decarboxylation and hydrolysis of SS were strengthened due to the catalysis effect. The N and S removal were promoted marginally. For hydrochar achieved from HTC process with H2O2 addition, the N and S removal were improved slightly due to the biopolymer oxidization by ‧OH released from H2O2 decomposition. While for HTC treatment with fly ash and H2O2 supplementation, a positive synergistic effect on N and S removal was observed. The N and S removal obtained from fly ash (10% of raw SS) and H2O2 (48 g/L) assisted HTC increased to 81.71% and 62.83%, respectively, from those of 69.53% and 49.92% in control group. N and S removal mechanism analysis suggested that hydroxyl radicals (‧OH) produced by H2O2 decomposition will destroy SS structure, and the biopolymers such as polysaccharides and proteins will be decomposed to release N and S into the liquid residue. In addition, the fly ash acts as the catalyst will decrease the energy need for denification and desulfartion. Consequently, N and S removal efficiency was enhanced by fly ash and H2O2 assisted HTC treatment.
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Affiliation(s)
- Xiaobo Wang
- National Research Base of Intelligent Manufacturing Service, Chongqing Technology and Business University, Chongqing, 400067, China; College of Environment and Resources, Chongqing Technology and Business University, Chongqing, 400067, China
| | - Yu Shen
- National Research Base of Intelligent Manufacturing Service, Chongqing Technology and Business University, Chongqing, 400067, China; College of Environment and Resources, Chongqing Technology and Business University, Chongqing, 400067, China; Chongqing South-to-Thais Environmental Protection Technology Research Institute Co., Ltd., Chongqing, 400069, China
| | - Xuecheng Liu
- College of Environment and Resources, Chongqing Technology and Business University, Chongqing, 400067, China
| | - Tengfei Ma
- National Research Base of Intelligent Manufacturing Service, Chongqing Technology and Business University, Chongqing, 400067, China; Chongqing South-to-Thais Environmental Protection Technology Research Institute Co., Ltd., Chongqing, 400069, China; Environmental Engineering Technology Research Center, Chongqing Academy of Ecological and Environmental Sciences, Chongqing, 401147, China
| | - Jin Wu
- Environmental Engineering Technology Research Center, Chongqing Academy of Ecological and Environmental Sciences, Chongqing, 401147, China
| | - Gaoxiang Qi
- National Research Base of Intelligent Manufacturing Service, Chongqing Technology and Business University, Chongqing, 400067, China; College of Environment and Resources, Chongqing Technology and Business University, Chongqing, 400067, China; Chongqing South-to-Thais Environmental Protection Technology Research Institute Co., Ltd., Chongqing, 400069, China.
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21
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Li X, Shi Y, Zhou X, Wang L, Zhang H, Pi K, Gerson AR, Liu D. Adaptability of organic matter and solid content to Fe 2+/persulfate and skeleton builder conditioner for waste activated sludge dewatering. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:14819-14829. [PMID: 34617233 DOI: 10.1007/s11356-021-16404-x] [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: 03/19/2021] [Accepted: 09/03/2021] [Indexed: 06/13/2023]
Abstract
Sludge conditioning is important for improved dewatering, with the sludge characteristics impacting the effect of conditioning. A composite conditioner, Fe2+-activated sodium persulfate (Fe2+/SPS) combined with phosphogypsum (PG), was used to examine its impact on sludges with different organic contents (34.6-43.8%) or different solid contents (2.8-5.9%). Response surface optimization analysis shows that when the best conditioning is achieved, the reduction of the specific resistance to filtration (SRF) is not sensitive to organic matter content, but the dewatering performance of the sludge is greatly affected by the solid content. The oxidation role of Fe2+/SPS and the skeleton builder role of PG together affect the conditioning, oxidation playing a major role in conditioning, especially for greater organic matter content. The organic content (maximum ηSOL value was 0.32) also affects the effectiveness of the skeleton builder more than the solid content (Maximum ηSOL value was 0.25). Changes in PG significantly impacts the optimal molar ratio and dosage of Fe2+/SPS. Sludge with greater solid content requires greater Fe2+/SPS dosage to provide stronger oxidation to destroy flocs, and the maximum Fe2+:SPS molar ratio was 1.14 with solid content of 5.9 wt%. The composite conditioning decreases the content of extracellular polymeric substances and proteins/polysaccharides. This study provides new insight into the relationship between the oxidation role of Fe2+/SPS and the skeleton builder role of PG for sludge conditioning strategies according to the optimal conditions.
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Affiliation(s)
- Xiaoran Li
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, 430068, Hubei, China
| | - Yafei Shi
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, 430068, Hubei, China.
- Hubei Key Laboratory of Ecological Restoration for River-Lakes and Algal Utilization, Wuhan, 430068, Hubei, China.
| | - Xi Zhou
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, 430068, Hubei, China
| | - Lu Wang
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, 430068, Hubei, China
| | - Huiqin Zhang
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, 430068, Hubei, China
| | - Kewu Pi
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, 430068, Hubei, China
- Hubei Key Laboratory of Ecological Restoration for River-Lakes and Algal Utilization, Wuhan, 430068, Hubei, China
| | - Andrea R Gerson
- Blue Minerals Consultancy, Wattle Grove, Tasmania, 7109, Australia
| | - Defu Liu
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, 430068, Hubei, China
- Hubei Key Laboratory of Ecological Restoration for River-Lakes and Algal Utilization, Wuhan, 430068, Hubei, China
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Ge D, Zhu Y, Li G, Yuan H, Zhu N. Identifying the key sludge properties characteristics in Fe 2+-activated persulfate conditioning for dewaterability amelioration and engineering implementation. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 296:113204. [PMID: 34243089 DOI: 10.1016/j.jenvman.2021.113204] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 06/29/2021] [Accepted: 06/30/2021] [Indexed: 06/13/2023]
Abstract
Fe2+-activated persulfate process has been introduced into sludge conditioning currently, however the key sludge properties characteristics are worthwhile comprehensively considering for the engineering implementation and management. The results indicated that both the optimal dosages of persulfate and Fe2+ were 0.6 mmol/gTS for sludge dewaterability amelioration, and the reduction efficiencies of capillary suction time (CST), specific resistance of filtration (SRF), and water content (Wc) of dewatered sludge cake reached to 90.5%, 97.2%, and 22.4%, respectively. Significantly, the persulfate and Fe2+ exerted distinctive roles in the conditioning process. The increased persulfate could promote the oxidatively disintegrated effect on sludge flocs, rendering the decrease of particle size. With the oxidative decomposition of the negatively charged biopolymers, sludge zeta potential rose gradually. However, Fe2+ contributed to more persulfate activation to generate free radicals, and the produced Fe3+ could further electrically neutralize the broken sludge fragments. The core mechanism of Fe2+-activated persulfate conditioning is "destroying and re-building" of sludge flocs. Noteworthily, EPS protein was oxidatively degraded more preferentially than EPS polysaccharide, and the decrease of the α-helix content of EPS protein was conducive to the enhancement of sludge dewaterability. Furthermore, the hydrophilic functional groups reduced clearly and element chemical states on sludge flocs altered pronouncedly, also the destroyed structure and microchannel facilitated the flowability of water. These findings provide theoretical and technical support for the practical engineering implementation of the Fe2+-activated persulfate conditioning process.
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Affiliation(s)
- Dongdong Ge
- School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yidan Zhu
- Jinhua Academy of Agricultural Sciences, Jinhua, Zhejiang, 321025, China
| | - Guobiao Li
- School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Haiping Yuan
- School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Nanwen Zhu
- School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China.
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23
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Gomes LA, Santos AF, Lopes RJA, Góis JC, Quina MJ. Isothermal drying kinetics of sewage sludge using weathered coal fly ash as adjuvant for agronomic application. ENVIRONMENTAL TECHNOLOGY 2021; 42:2267-2277. [PMID: 31791200 DOI: 10.1080/09593330.2019.1700311] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 11/26/2019] [Indexed: 06/10/2023]
Abstract
This study aims to evaluate the effect of weathered coal fly ash (CFA) as a drying adjuvant of sewage sludge (SS) to produce a soil amendment. The high amount of SS and CFA creates a complex waste management problem in many countries, requiring more research efforts. Towards a circular economy, CFA can be viewed as an anthropogenic inorganic by-product with valuable nutrients (e.g. K), which can be recovered in combination with SS (rich in organic matter, N, and P). Different temperatures (70, 85, 100, 115, and 130 °C) are tested to dry small SS cylinders, without and with 0.15 g CFA g-1 of SSwet basis (wb). By fitting appropriate models to the experimental drying curves, it is possible to observe an improvement of 1-17% in the diffusion coefficient and 7-19% in the kinetic constants, using CFA. The best drying conditions are achieved with CFA as an adjuvant at 130 °C, where the drying rate is 31.61 gH2O kg-1 SSwb min-1. Phytotoxicity and growth assays are performed to evaluate the effect of the produced materials in the soil. The product with SS and CFA shows the potential to improve soil condition due to (i) the organic matter, N, P, and K content, (ii) the lower phytotoxic effect when compared to raw SS; (iii) the soil pH correction. Thus, not only the addition of weathered CFA facilitates the drying of SS but also the final product has benefits to soil conditions.
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Affiliation(s)
- Luciano A Gomes
- CIEPQPF - Centre of Chemical Processes Engineering and Forest Products, Department of Chemical Engineering, University of Coimbra, Rua Sílvio Lima, Portugal
- IFB - Federal Institute of Education, Science, and Technology of Brasília - IFB, Campus Ceilândia Brasília - Federal District, Brazil
| | - Andreia F Santos
- CIEPQPF - Centre of Chemical Processes Engineering and Forest Products, Department of Chemical Engineering, University of Coimbra, Rua Sílvio Lima, Portugal
| | - Rui J A Lopes
- CIEPQPF - Centre of Chemical Processes Engineering and Forest Products, Department of Chemical Engineering, University of Coimbra, Rua Sílvio Lima, Portugal
| | - José C Góis
- Association for the Development of Industrial Aerodynamics, Department of Mechanical Engineering, University of Coimbra, Coimbra, Portugal
| | - Margarida J Quina
- CIEPQPF - Centre of Chemical Processes Engineering and Forest Products, Department of Chemical Engineering, University of Coimbra, Rua Sílvio Lima, Portugal
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24
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Wang Q, Song L, Hui K, Song H. Iron powder activated peroxymonosulfate combined with waste straw to improve sludge dewaterability. ENVIRONMENTAL TECHNOLOGY 2021; 42:1302-1311. [PMID: 31487232 DOI: 10.1080/09593330.2019.1665111] [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: 06/10/2019] [Accepted: 08/31/2019] [Indexed: 06/10/2023]
Abstract
In an activated sludge system, the high hydrophilicity of extracellular polymeric substances (EPS) and the high compressibility of sludge greatly hinder sludge dewatering. A new method for improving the dehydration of waste activated sludge was explored by using iron powder activated peroxomonosulfate combined with waste straw (Fe0+PMS + WS). Specific resistance to filtration (SRF) and water content (Wc) were used to characterize the dewatering performance of sludge. Under the optimal measurement, Wc and SRF were significantly reduced. To reveal the synergistic effect of this joint treatment, zeta potential, particle size distribution, three-dimension excitation emission matrix (3D-EEM) fluorescence spectroscopy, bound water content analysis, and scanning electron microscopy (SEM) were used to investigate the mechanism of sludge dewatering. Results showed that the tightly bound EPS (TB-EPS) was oxidized by sulfate radicals (SO4-∙) to loose bound EPS (LB-EPS) and soluble EPS(S-EPS). SEM analysis displayed that the Fe0+PMS + WS combination regulated the formation of a more porous sludge filter cake structure. In addition, the low calorific value of the dewatered sludge after 12 h in open air was significantly increased, and the Wc of the dewatered sludge cake was reduced to 25%. These parameters were beneficial to the subsequent disposal of sludge.
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Affiliation(s)
- Qian Wang
- School of Civil Engineering, Inner Mongolia University of Technology, Hohhot, People's Republic of China
| | - Lei Song
- School of Civil Engineering, Inner Mongolia University of Technology, Hohhot, People's Republic of China
| | - Kai Hui
- School of Civil Engineering, Inner Mongolia University of Technology, Hohhot, People's Republic of China
| | - Hongwei Song
- School of Civil Engineering, Inner Mongolia University of Technology, Hohhot, People's Republic of China
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25
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Ruan S, Deng J, Cai A, Chen S, Cheng Y, Li J, Li Q, Li X. Improving dewaterability of waste activated sludge by thermally-activated persulfate oxidation at mild temperature. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 281:111899. [PMID: 33418390 DOI: 10.1016/j.jenvman.2020.111899] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 12/08/2020] [Accepted: 12/23/2020] [Indexed: 06/12/2023]
Abstract
The mass production of waste activated sludge in wastewater treatment plants may lead to environmental pollution and sludge dewatering is an essential process during its treatment. The oxidation of extracellular polymeric substances (EPS) was the core step to achieve deep sludge dewatering. In this study, thermally-activated sodium persulfate (SPS) process was managed to improve the dewaterability of waste activated sludge (WAS) and its internal mechanism was systematically elaborated. Experimental results showed that with 2.0 mmol/g VSS SPS at 80 °C, capillary suction time (CST) was roughly 59.74% of that in raw sludge. Under this condition, 14.66 ± 0.10 × 1011 kg/m of specific resistance to filtration (SRF) and 61.8% ± 0.1% of water content (WC) was determined, respectively. A solubilization/oxidation process was proposed to unravel the mechanism of the enhanced dewaterability of WAS in thermally-activated SPS process. Mild temperature efficiently disrupted the sludge flocs and broke cell walls, releasing large amounts of EPS into bulk phase. Meanwhile, mild temperature accelerated the decomposition of SPS to generate sulfate radicals (SO4-) and hydroxyl radicals (OH) for oxidizing EPS, facilitating the conversion of bound hydrated water into free water and achieving solid-water separation. The higher reaction temperature favored sludge dewatering, whereas overdosing SPS posed no significant impact. Further analysis illustrated that tyrosine protein-like, tryptophan protein-like, fulvic acid-like and humic acid-like substances in various EPS fractions together exerted the influence on sludge dewatering. Furthermore, the synergy process could alter the secondary structure of protein, which caused a loose structure of EPS and the exposure of hydrophobic sites, facilitating the dehydration of sludge flocs. The details of how thermally-activated SPS process enhanced sludge dewaterability provided the theoretical and technical basis for the application of the process under a real-world situation.
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Affiliation(s)
- Shuyu Ruan
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou, 310023, China
| | - Jing Deng
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou, 310023, China.
| | - Anhong Cai
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou, 310023, China
| | - Shengnan Chen
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou, 310023, China
| | - Yongqing Cheng
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou, 310023, China
| | - Jun Li
- College of Environment, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Qingsong Li
- Water Resources and Environmental Institute, Xiamen University of Technology, Xiamen, 361005, China
| | - Xueyan Li
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China
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Liu Y, Wang M, Chen M, Zhu M, Liao M. Facilitating the natural semi-drying of oily sludge by changing the form of water. PLoS One 2021; 16:e0245430. [PMID: 33444389 PMCID: PMC7808663 DOI: 10.1371/journal.pone.0245430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 01/03/2021] [Indexed: 11/24/2022] Open
Abstract
Reducing the water content of oily sludge is essential for the disposal of it. Despite conditioning and solid-liquid separation, the water content of oily sludge generally exceeds 65%. A large amount of this water exists in the form of emulsified and bound water, reducing the efficiency of water removal during the natural semi-drying process of oily sludge. To shorten the time required for natural semi-drying, this study applied an orthogonal test to screen an oily sludge modified material (OSM). The effect and mechanism of OSM on the natural semi-drying of oily sludge were studied using a thermal gravimetric analyzer (TGA), scanning electron microscope (SEM), surface tension measurement, and microscopic observations. The results show that when the ambient temperature exceeded 10°C, the OSM increased in mass by 8-10%, and the time required for the natural semi-drying of oily sludge was shortened from 15 days to less than 5 days. OSM can rupture the emulsion, reduce the surface tension, convert the emulsion and bound water in the oily sludge into free water, and accelerate the rate of water migration, diffusion, and natural evaporation from the inside of the oily sludge to the surface and air. The research results show that changing the form of water can speed up the drying of oily sludge, creating positive economic benefits in the process of oily sludge reduction and recycling.
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Affiliation(s)
- Yucheng Liu
- College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan, P R of China
- Research Institute of Industrial Hazardous Waste Disposal and Resource Utilization, Southwest Petroleum University, Chengdu, Sichuan, P R of China
| | - Maoren Wang
- College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan, P R of China
| | - Mingyan Chen
- College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan, P R of China
- Research Institute of Industrial Hazardous Waste Disposal and Resource Utilization, Southwest Petroleum University, Chengdu, Sichuan, P R of China
| | - Meng Zhu
- College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan, P R of China
| | - Maoqi Liao
- College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan, P R of China
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27
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Wang M, Wu Y, Yang B, Deng P, Zhong Y, Fu C, Lu Z, Zhang P, Wang J, Qu Y. Comparative study of the effect of rice husk-based powders used as physical conditioners on sludge dewatering. Sci Rep 2020; 10:17230. [PMID: 33057131 PMCID: PMC7560731 DOI: 10.1038/s41598-020-74178-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 09/24/2020] [Indexed: 11/17/2022] Open
Abstract
The effects of rice husk flour (RHF), rice husk biochar (RHB), and rice husk-sludge cake biochar (RH-SCB, expresses sludge cake biochar deriving from a sludge that has been previously conditioned with rice husk) used as physical conditioners on sludge dewaterability were compared. The effects of characteristics of physical conditioners on sludge compressibility and zeta potential were analyzed. The optimal rice husk-based powder was RH-SCB, which presented the highest net sludge solid yield (YN, expresses the dry mass flow by filtration) at 20.39 kg/(m2 h) for 70% dry sludge (DS). Characterization analysis indicates that the hardness and surface Fe content of powders which could influence the compressibility coefficient of sludge cake and sludge zeta potential were the major factors influencing sludge dewaterability. The comparison of feasibility and economic analysis showed that adding RH-SCB improves the quality of the sludge filtrate and reduces the pollution potential of conditioned sludge (the ratio of secondary and primary (RSP) of Cu, Zn, Cd reduces from 43.05, 144.00, 7.25 to 7.89, 14.63, 4.27, respectively), and the costs of using RH-SCB were the lowest (at 88.4% lower than that of the raw sludge). Therefore, it is feasible to use RH-SCB to improve sludge dewaterability.
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Affiliation(s)
- Maoqing Wang
- Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir, Chongqing Three Gorges University, 404100, Wan Zhou, Chongqing, People's Republic of China
| | - Yan Wu
- Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir, Chongqing Three Gorges University, 404100, Wan Zhou, Chongqing, People's Republic of China. .,College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, People's Republic of China. .,Jiangsu Tian Hong Environmental Engineering Co., Ltd, Yangzhou, 225000, People's Republic of China.
| | - Binrong Yang
- Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir, Chongqing Three Gorges University, 404100, Wan Zhou, Chongqing, People's Republic of China
| | - Peiyao Deng
- Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir, Chongqing Three Gorges University, 404100, Wan Zhou, Chongqing, People's Republic of China
| | - Yinhai Zhong
- Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir, Chongqing Three Gorges University, 404100, Wan Zhou, Chongqing, People's Republic of China
| | - Chuan Fu
- Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir, Chongqing Three Gorges University, 404100, Wan Zhou, Chongqing, People's Republic of China.
| | - Zenghui Lu
- Chongqing Wanzhou Ecological Environmental Monitoring Station, 404100, Wan Zhou, People's Republic of China
| | - Panyue Zhang
- Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir, Chongqing Three Gorges University, 404100, Wan Zhou, Chongqing, People's Republic of China. .,College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, People's Republic of China.
| | - Jueqiao Wang
- Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir, Chongqing Three Gorges University, 404100, Wan Zhou, Chongqing, People's Republic of China
| | - Yuyang Qu
- Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir, Chongqing Three Gorges University, 404100, Wan Zhou, Chongqing, People's Republic of China
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28
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Ricciardi P, Cillari G, Carnevale Miino M, Collivignarelli MC. Valorization of agro-industry residues in the building and environmental sector: A review. WASTE MANAGEMENT & RESEARCH : THE JOURNAL OF THE INTERNATIONAL SOLID WASTES AND PUBLIC CLEANSING ASSOCIATION, ISWA 2020; 38:487-513. [PMID: 32089127 DOI: 10.1177/0734242x20904426] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Environmental pollution has become a relevant issue as the population rises and resources decrease. Reuse and recycling still have the greatest potential as they turn the waste into a new resource, representing the 'closed-loop' step of a circular economy (CE). Looking for new applications for agro-industry waste represents both an environmental issue, as its incorrect disposal is a cause of pollution, and a chance to exploit zero-cost natural wastes. The present review, with around 200 articles examined, focuses on possible reuses of these residues in (a) building construction, as additives to produce thermal and acoustic insulation panels, and (b) in water treatments, exploited for removal of pollutants. The selected materials (coconut, coffee, corn, cotton and rice) have industry production wastes with suitable applications in both sectors and huge worldwide availability; their reuse may thus represent a new resource, with an impact based on the production rate and the possible replacement of current inorganic materials. Along with possible implementation of the selected materials in the building industry and environmental engineering, a brief description of the production and supply chain are provided.
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Affiliation(s)
- Paola Ricciardi
- Department of Civil Engineering and Architecture, University of Pavia, Italy
| | - Giacomo Cillari
- Department of Civil Engineering and Architecture, University of Pavia, Italy
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29
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Hubert C, Steiniger B, Schaum C. Residues from the dairy industry as co-substrate for the flexibilization of digester operation. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2020; 92:534-540. [PMID: 31386784 DOI: 10.1002/wer.1197] [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: 04/25/2019] [Revised: 07/29/2019] [Accepted: 08/02/2019] [Indexed: 06/10/2023]
Abstract
Water resource recovery facilities (WRRF) can make an important contribution to increase the share of renewable energies in Germany. In this context, it is important to utilize unused digester capacities on WRRF. In addition, a demand-orientated biogas production could synchronize electricity demand and electricity generation and improve the overall energetic balance of the WRRF. As part of the project "Water Resource Recovery Facilities in interaction with the waste and energy industry: A German-Austrian Dialogue - COMITO," the influence of residues from the dairy industry on the digestion process was examined as well as the suitability for the flexibilization of digester gas production. Four reactors were fed with different amounts of flotation sludge from the dairy industry for several months. The difference in the feed resulted in organic loading (OLR) rates between 3.2 kg COD/(m3 day) and 6 kg COD/(m3 day). The reactors were fed with a daily shock load. The investigations showed that volumetric loads up to 4.4 kg COD/(m3 day) did not lead to an accumulation of organic acids. Organic loading rate of 6 kg COD/(m3 day) showed a significant accumulation of organic acids higher than 2,500 mg/L oHAc. Nevertheless, the reactor could be operated with a degradation rate of 71% with a corresponding biogas yield with a methane content of 71%. With increasing flotation sludge content, a higher concentration in ammonium of up to 2.000 mg/L NH4 -N could be detected in the effluent of the digester. Despite higher phosphorus concentration in the flotation sludge, the concentration of PO4 -P remained constant for all reactors fluctuating between 20 and 40 mg/L PO4 -P. Dewatering worsened significantly with increasing levels of flotation sludge. PRACTITIONER POINTS: Main purpose of the research is to flexibilize digester operation on WRRF using flotation sludges from the dairy industry. Flexibilization of the digester using flotation sludge is possible up to an organic load of 6 kg COD/(m3 day). Higher NH4 -N concentration in the effluent of the digester must be accepted when using higher amounts of flotation sludge. Phosphate concentration in the effluent of the digester remained on a low level despite higher phosphorus content in the flotation sludge. High levels of organic acids (mainly acetic acid) can be tolerated and can be recovered within a short time after reducing the load.
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Affiliation(s)
- Christian Hubert
- Department for Civil Engineering and Environmental Sciences, Bundeswehr University Munich, Neubiberg, Germany
| | - Bettina Steiniger
- Department for Civil Engineering and Environmental Sciences, Bundeswehr University Munich, Neubiberg, Germany
| | - Christian Schaum
- Department for Civil Engineering and Environmental Sciences, Bundeswehr University Munich, Neubiberg, Germany
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30
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Shi Q, Lu Y, Guo W, Wang T, Zhu Q, Zhang Y, Wang H, Li F, Xu T, Li C. Application of a cellulose filter aid in municipal sewage sludge dewatering and drying: Jar, pilot, and factory scale. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2020; 92:495-503. [PMID: 31587441 DOI: 10.1002/wer.1254] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 10/01/2019] [Accepted: 10/03/2019] [Indexed: 06/10/2023]
Abstract
Cellulose filter aid (CFA), a skeleton builder, has been studied for sludge conditioning at laboratory scale because of its function in reducing compressibility of sludge cake. However, there are few practical applications of CFA at the pilot and factory scales. In this study, we combined CFA with an advanced sludge dewatering technology, in practical applications. For jar test, the optimum CFA dose was 3 wt.% dry solid (DS); furthermore, the combination of CFA with polyaluminum chloride (PAC) and polyacrylamide (PAM) resulted in the lowest moisture content (73.92%) and the highest calorific value (13,628 kJ/kg) of the sludge cake. In the pilot test, the 5 wt.% DS of the CFA resulted in the optimal sludge feeding amount. In the factory test, the optimal CFA dose was further increased to 10%, and the amount of sludge feeding in a single batch was 20.5% higher than that without CFA. The optimal dose of CFA in the jar-pilot-factory test increased, which may occur because the CFA more easily penetrated the cake and performed better in building the skeleton when the sludge cake was thin. This study could provide a reference for the application of CFA and other skeleton builders in sludge dewatering and drying. PRACTITIONER POINTS: An advanced sludge treatment process-low-temperature vacuum dewatering and drying was tested. Cellulose filter aid showed good effect in jar test, pilot test, and factory test. When the scale of the experiment was from jar to factory, the optimal dosage of the cellulose filter aid was magnified. The amplification phenomenon of optimal dosage was related to the distribution pattern of cellulose filter aid in different thickness mud cakes.
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Affiliation(s)
- Qi Shi
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, UNEP-TONGJI Institute of Environment for Sustainable Development, Tongji University, Shanghai, China
- Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, China
| | - Yufei Lu
- Shanghai CEO Environmental Protection Technology Co., Ltd., Shanghai, China
- National Petroleum and Chemical Industry Environmental Protection Engineering Center of Sludge Dewatering and Drying Treatment and Disposal, Shanghai, China
| | - Wenjing Guo
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, UNEP-TONGJI Institute of Environment for Sustainable Development, Tongji University, Shanghai, China
- Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, China
| | - Tianrun Wang
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, UNEP-TONGJI Institute of Environment for Sustainable Development, Tongji University, Shanghai, China
- Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, China
| | - Qinyun Zhu
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, UNEP-TONGJI Institute of Environment for Sustainable Development, Tongji University, Shanghai, China
- Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, China
| | - Yaxian Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, UNEP-TONGJI Institute of Environment for Sustainable Development, Tongji University, Shanghai, China
- Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, China
| | - Hongtao Wang
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, UNEP-TONGJI Institute of Environment for Sustainable Development, Tongji University, Shanghai, China
- Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, China
| | - Fengting Li
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, UNEP-TONGJI Institute of Environment for Sustainable Development, Tongji University, Shanghai, China
- Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, China
| | - Taiming Xu
- Shanghai CEO Environmental Protection Technology Co., Ltd., Shanghai, China
- National Petroleum and Chemical Industry Environmental Protection Engineering Center of Sludge Dewatering and Drying Treatment and Disposal, Shanghai, China
| | - Chunjiang Li
- Shanghai CEO Environmental Protection Technology Co., Ltd., Shanghai, China
- National Petroleum and Chemical Industry Environmental Protection Engineering Center of Sludge Dewatering and Drying Treatment and Disposal, Shanghai, China
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31
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Wójcik M. Investigation of filtration properties and microbiological characteristics of sewage sludge after physical conditioning with the use of ground walnut shells. POWDER TECHNOL 2020. [DOI: 10.1016/j.powtec.2019.11.100] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Xu ZX, Song H, Deng XQ, Zhang YY, Xue-Qin M, Tong SQ, He ZX, Wang Q, Shao YW, Hu X. Dewatering of sewage sludge via thermal hydrolysis with ammonia-treated Fenton iron sludge as skeleton material. JOURNAL OF HAZARDOUS MATERIALS 2019; 379:120810. [PMID: 31255849 DOI: 10.1016/j.jhazmat.2019.120810] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 04/22/2019] [Accepted: 06/21/2019] [Indexed: 06/09/2023]
Abstract
In this study, the alkaline hydrothermal ferric carbon (AHFC), which was prepared by hydrothermal liquefaction method using Fenton iron sludge with NH3·H2O, was used as a skeleton materials for the dewatering of sewage sludge (SS) via thermal hydrolysis. NH2 functional group presented in the AHFC and nano-sized γ-Fe2O3 was anchored on the surface of AHFC. The NH2 functional group notably promoted thermal hydrolysis of SS from the increasing of TOC and TN value. γ-Fe2O3 showed adsorption effect to the water, resulting in decline of the dewatering rate of SS in present condition. When 100% of AHFC was added, dewatering rate of SS was decreased by 19.93% (at 160 °C), 4.50% (at 180 °C) and 8.34% (at 200 °C) respectively. 3D-EEM results showed that the degree of hydrolysis was deepened when AHFC was added for the intensity of soluble microbial products decline. AHFC promoted the decomposition of protein to form heterocycle compounds in the resulting cake according to in situ FTIR results. The nano γ-Fe2O3 catalysis to cake also can be observed for the activation energy was lower than blank in the range of 40˜60%. The study demonstrated concept and the effectiveness the reuse/recycle of the Fenton iron sludge for dewatering of SS.
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Affiliation(s)
- Zhi-Xiang Xu
- School of Energy and Power Engineering, Jiangsu University, Zhenjiang, 212013, China.
| | - Hao Song
- School of Energy and Power Engineering, Jiangsu University, Zhenjiang, 212013, China
| | - Xiao-Qiang Deng
- School of Energy and Power Engineering, Jiangsu University, Zhenjiang, 212013, China
| | - Yu-Yue Zhang
- School of Energy and Power Engineering, Jiangsu University, Zhenjiang, 212013, China
| | - Ma Xue-Qin
- School of Energy and Power Engineering, Jiangsu University, Zhenjiang, 212013, China
| | - Si-Qi Tong
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China
| | - Zhi-Xia He
- Institute for Energy Research, Jiangsu University, Zhenjiang, 212013, China
| | - Qian Wang
- School of Energy and Power Engineering, Jiangsu University, Zhenjiang, 212013, China
| | - Yue-Wen Shao
- School Materials Science and Engineering, University of Jinan, Jinan, 250022, China
| | - Xun Hu
- School Materials Science and Engineering, University of Jinan, Jinan, 250022, China.
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Wang T, Xue Y, Hao R, Hou H, Liu J, Li J. Mechanism investigations into the effect of rice husk and wood sawdust conditioning on sewage sludge thermal drying. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 239:316-323. [PMID: 30921750 DOI: 10.1016/j.jenvman.2019.03.074] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 03/01/2019] [Accepted: 03/16/2019] [Indexed: 06/09/2023]
Abstract
This study attempts to employ wood sawdust and rice husk as biorenewable conditioners to improve the efficiency and energy consumption of sewage sludge thermal drying, besides revealing the mechanism of drying. Response surface methodology (RSM) approach has been used to optimize the operational parameters (drying temperature and dose of conditioners). Investigations into the thermal performance, water distribution and morphological of sludge have been used to explain the improvements obtained in the properties of drying with the addition of biomass. The optimal conditions found out were: 10% rice husk and 10% wood sawdust at 120 °C, which resulted in drying time to reduce by 17.64% with the energy consumption savings by 46.37% for the conditioned sludge. Also, the mechanism on the roles of these additives has been found out as follows: (1) Addition of biomass enhances the thermal conductivity of the conditioned sludge, leading to improvements in its heat transfer capacity; (2) Bound water → free water and strongly bonding water → weakly bonding water, due to cationic osmotic effects; (3) Structures with rigidity and porosity provide sufficient passages for the vapors to escape.
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Affiliation(s)
- Teng Wang
- School of Environmental Engineering, Wuhan Textile University, Wuhan, 430073, China; Engineering Research Centre for Clean Production of Textile Dyeing and Printing, Ministry of Education, Wuhan Textile University, Wuhan, 430073, China
| | - Yongjie Xue
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, 430070, Hubei, Wuhan, China
| | - Rong Hao
- Changjiang Institute of Survey, Planning, Design and Research, 430014, Hubei, Wuhan, China
| | - Haobo Hou
- School of Resource and Environment Science, Wuhan University, 430070, Hubei, Wuhan, China.
| | - Jingxin Liu
- School of Environmental Engineering, Wuhan Textile University, Wuhan, 430073, China; Engineering Research Centre for Clean Production of Textile Dyeing and Printing, Ministry of Education, Wuhan Textile University, Wuhan, 430073, China
| | - Jinping Li
- School of Environmental Engineering, Wuhan Textile University, Wuhan, 430073, China; Engineering Research Centre for Clean Production of Textile Dyeing and Printing, Ministry of Education, Wuhan Textile University, Wuhan, 430073, China.
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