1
|
Makoś-Chełstowska P, Słupek E, Gębicki J. Agri-food waste biosorbents for volatile organic compounds removal from air and industrial gases - A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 945:173910. [PMID: 38880149 DOI: 10.1016/j.scitotenv.2024.173910] [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: 04/28/2024] [Revised: 06/06/2024] [Accepted: 06/08/2024] [Indexed: 06/18/2024]
Abstract
Approximately 1.3 billion metric tons of agricultural and food waste is produced annually, highlighting the need for appropriate processing and management strategies. This paper provides an exhaustive overview of the utilization of agri-food waste as a biosorbents for the elimination of volatile organic compounds (VOCs) from gaseous streams. The review paper underscores the critical role of waste management in the context of a circular economy, wherein waste is not viewed as a final product, but rather as a valuable resource for innovative processes. This perspective is consistent with the principles of resource efficiency and sustainability. Various types of waste have been described as effective biosorbents, and methods for biosorbents preparation have been discussed, including thermal treatment, surface activation, and doping with nitrogen, phosphorus, and sulfur atoms. This review further investigates the applications of these biosorbents in adsorbing VOCs from gaseous streams and elucidates the primary mechanisms governing the adsorption process. Additionally, this study sheds light on methods of biosorbents regeneration, which is a key aspect of practical applications. The paper concludes with a critical commentary and discussion of future perspectives in this field, emphasizing the need for more research and innovation in waste management to fully realize the potential of a circular economy. This review serves as a valuable resource for researchers and practitioners interested in the potential use of agri-food waste biosorbents for VOCs removal, marking a significant first step toward considering these aspects together.
Collapse
Affiliation(s)
- Patrycja Makoś-Chełstowska
- Department of Process Engineering and Chemical Technology, Faculty of Chemistry, Gdansk University of Technology, 80-233 Gdańsk, Poland.
| | - Edyta Słupek
- Department of Process Engineering and Chemical Technology, Faculty of Chemistry, Gdansk University of Technology, 80-233 Gdańsk, Poland
| | - Jacek Gębicki
- Department of Process Engineering and Chemical Technology, Faculty of Chemistry, Gdansk University of Technology, 80-233 Gdańsk, Poland
| |
Collapse
|
2
|
Yu Y, Sun X, Zhang H, Wu W, Zhang T, Ge S. Multiscale experimental insights into vacuum drying of sludge for enhanced energy efficiency and emission control. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 939:173592. [PMID: 38810745 DOI: 10.1016/j.scitotenv.2024.173592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 05/08/2024] [Accepted: 05/26/2024] [Indexed: 05/31/2024]
Abstract
This study provides a comprehensive analysis of the vacuum drying process for sludge drying, with a focus on optimizing energy efficiency and emission control. The study used both lab-scale static and pilot-scale vacuum drying systems to test various parameters like vacuum levels, heat source temperatures, and sludge thicknesses. The results indicated that optimal drying conditions were achieved at a vacuum level of -0.06 MPa, a heat temperature of 140 °C, and a sludge thickness of 3.4 mm, where the drying rate reaches 0.13278 g·g-1·min-1. The study underscores the significant influence of vacuum level, temperature, and sludge thickness on drying rates. The Page model was used to analyze drying kinetics, elucidating how changes in these parameters affect drying characteristics. Furthermore, the study also examined the pollutant emissions and energy efficiency at the pilot scale. It found that high vacuum environments could efficiently dry sludge using low-temperature heat source, leading to average energy consumption per unit evaporation of 3020.29 kJ/kg, which is lower compared to traditional methods. By harnessing low-grade industrial waste heat, this can be further reduced to 875.76 kJ/kg. This study offers valuable insights for sustainable sludge management systems, highlighting the environmental and economic benefits of vacuum drying technology. The detailed experimental approach and thorough analysis make a significant contribution to the field of the sludge drying.
Collapse
Affiliation(s)
- Yang Yu
- School of Energy and Environment, MOE Key Laboratory of Environmental Medicine Engineering, Southeast University, Nanjing 210096, China.
| | - Xiaofeng Sun
- School of Energy and Environment, MOE Key Laboratory of Environmental Medicine Engineering, Southeast University, Nanjing 210096, China
| | - Huarong Zhang
- Fujian Longjing Co., Ltd., Fujian, Longyan 364000, China
| | - Weihong Wu
- Fujian Longjing Co., Ltd., Fujian, Longyan 364000, China
| | - Tianxing Zhang
- Fujian Longjing Co., Ltd., Fujian, Longyan 364000, China
| | - Shifu Ge
- School of Energy and Environment, MOE Key Laboratory of Environmental Medicine Engineering, Southeast University, Nanjing 210096, China.
| |
Collapse
|
3
|
Zheng Q, Ni L. Analysis of the effect of intrinsic sludge properties on sludge drying characteristics from both sludge composition and type scales. WASTE MANAGEMENT (NEW YORK, N.Y.) 2024; 183:278-289. [PMID: 38781819 DOI: 10.1016/j.wasman.2024.05.020] [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: 08/01/2023] [Revised: 04/08/2024] [Accepted: 05/15/2024] [Indexed: 05/25/2024]
Abstract
Convective drying is an effective method for reducing the moisture content of the sludge. Fewer studies have discussed the effect of sludge physicochemical properties on drying compared to air parameters. Eleven types of sludge were collected, and ultimate analysis, proximate analysis, and heat value analysis were performed. Meanwhile, the maximum drying rate (umax) of sludge convection drying at 70 °C was determined. The results showed that the cumulative variance contribution of the two extracted principal components (PCs) was 92.5 %. Then, a regression model of umax was developed based on the extracted PCs. The coefficient of determination of this model was 0.788, and the difference was statistically significant, with a negative correlation between umax and PC2. Further, the principal component score plot enabled the traceability of the integrated sludge, and based on this classification results, the drying characteristics of various types of sludge were discussed, and a high correlation (R2 = 0.9590) between the initial moisture content of sludge and umax was found. Mathematical models between sludge physicochemical properties and drying characteristics can be effectively developed from both sludge composition and type scales. This exploration deepened the knowledge of sludge drying and facilitates the prediction of drying rate.
Collapse
Affiliation(s)
- Qiushuang Zheng
- School of Architecture and Design, Harbin Institute of Technology, Key Laboratory of Cold Region Urban and Rural Human Settlement Environment Science and Technology, Ministry of Industry and Information Technology, Harbin, China
| | - Long Ni
- School of Architecture and Design, Harbin Institute of Technology, Key Laboratory of Cold Region Urban and Rural Human Settlement Environment Science and Technology, Ministry of Industry and Information Technology, Harbin, China.
| |
Collapse
|
4
|
Ma L, Zhao R, Li J, Yang Q, Zou K. Release characteristics and risk assessment of volatile sulfur compounds in municipal wastewater treatment plants. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 350:123946. [PMID: 38643932 DOI: 10.1016/j.envpol.2024.123946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Revised: 03/15/2024] [Accepted: 04/06/2024] [Indexed: 04/23/2024]
Abstract
In recent years, the malodorous gases generated by sewage treatment plants have gradually received widespread attention due to their sensory stimulation and health hazards. The emission concentration, sensory evaluation and health risk assessment of volatile sulfur compounds (VSCs) were all explored in two municipal wastewater treatment plants (WWTPs) with oxidation ditch and anaerobic/oxic treatment process, respectively. The VSCs concentration showed the highest amount in the primary treatment unit in both the two WWTPs (73.3% in Plant A and 93.0% in Plant B), while the H2S took the main role in the composition of VSCs. However, H2S took a larger percentage in Plant A (84.5% ∼ 87.0%) rather than Plant B (61.2% ∼ 83.5%), which may be due to the different operating conditions and sludge properties in different treatment process. Besides, H2S also gained the first rank in the sensory evaluation and health risk assessment, which may cause considerable sensory irritation and health risk to workers and surrounding residents. Furthermore, the influencing factor analyses of VSCs emission showed that the temperature of water and air, ORP of sludge made the greatest effect on VSCs release. This study provides theoretical and data support for the research of VSCs emission control in WWTPs.
Collapse
Affiliation(s)
- Linlin Ma
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing, 100124, China; Key Laboratory of Odor Pollution Control in Ministry of Ecology and Environment of the People's Republic of China, Tianjin Academy of Eco-environmental Sciences, Tianjin, 300191, China
| | - Ruhan Zhao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing, 100124, China
| | - Jiaxin Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing, 100124, China
| | - Qing Yang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing, 100124, China.
| | - Kehua Zou
- Key Laboratory of Odor Pollution Control in Ministry of Ecology and Environment of the People's Republic of China, Tianjin Academy of Eco-environmental Sciences, Tianjin, 300191, China
| |
Collapse
|
5
|
Wang Y, Liu Y, Yang K, Yang L, Zhang S, Ba Y, Zhou G. The bioaerosols generated from the sludge treatment process: Bacterial and fungal variation characteristics, source tracking, and risk assessment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 903:166193. [PMID: 37567309 DOI: 10.1016/j.scitotenv.2023.166193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 08/08/2023] [Accepted: 08/08/2023] [Indexed: 08/13/2023]
Abstract
Bioaerosols generated from sludge treatment processes in wastewater treatment plants (WWTPs) may spread infectious diseases. This study investigated the generation characteristics, source, and associated risks of bioaerosols produced during sludge treatment processes. The results showed that the concentration range of total suspended particles was 49 ± 3 to 354 ± 10 μg/m3, and the primary water-soluble ions in bioaerosols were NH4+, SO42- and Cl-. The bacterial concentration in bioaerosols was 50 ± 5 to 1296 ± 261 CFU/m3, with the highest concentration in the biochemical reaction tank. The dominant bacteria in bioaerosols included Bacteroides, Cetobacterium, Romboutsia, Lactobacillus and Turicibacter, while the dominant fungi were Aspergillus, Alternaria, Cladosporium and Fusarium. Pathogenic microorganisms such as Escherichia and Aspergillus were detected in all treatment processes. The results of principal component analysis showed that the bacterial composition in bioaerosols was similar of different technological processes, while the fungal species composition was different. The dominant microbial composition of sludge and bioaerosols was relatively close. The Source Tracker results indicated that sludge was the main source of airborne bacteria in the sludge dewatering house, as well as the main source of airborne fungi in the plate-frame pressure filtration tank and the sloping plate sedimentation tank. The non-carcinogenic risk in each stage was low (1.22 × 10-9-3.99 × 10-2). However, Bugbase phenotype prediction results showed that the bioaerosols in the anaerobic sedimentation tank may have potential pathogenicity. Therefore, the management and control of bioaerosols from the sludge treatment should be strengthened.
Collapse
Affiliation(s)
- Yanjie Wang
- School of Public Health, Zhengzhou University, Zhengzhou 450001, PR China.
| | - Yang Liu
- School of Public Health, Zhengzhou University, Zhengzhou 450001, PR China.
| | - Kai Yang
- School of Public Health, Zhengzhou University, Zhengzhou 450001, PR China.
| | - Liying Yang
- School of Public Health, Zhengzhou University, Zhengzhou 450001, PR China.
| | - Song Zhang
- School of Public Health, Zhengzhou University, Zhengzhou 450001, PR China.
| | - Yue Ba
- School of Public Health, Zhengzhou University, Zhengzhou 450001, PR China.
| | - Guoyu Zhou
- School of Public Health, Zhengzhou University, Zhengzhou 450001, PR China.
| |
Collapse
|
6
|
Lu M, Xue Y, Zhao H, Zhang X, Wang T. Effect of electromagnetic induction drying on the drying-incineration process of dyeing sludge: focus on migration and conversion of sulfur. WASTE MANAGEMENT (NEW YORK, N.Y.) 2023; 171:522-531. [PMID: 37806160 DOI: 10.1016/j.wasman.2023.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 09/15/2023] [Accepted: 10/03/2023] [Indexed: 10/10/2023]
Abstract
Secondary sulfur pollution in dyeing sludge (DS) during drying and incineration is a major environmental problem necessitating in-situ control. To robustly immobilise sulfur during drying-incineration, the authors introduce an electromagnetic induction (EMI) drying method and reveal the corresponding migration and conversion of sulfur in DS. The EMI-drying efficiency reached 10.69%/min, five times that of thermal drying. EMI drying increases the relative sulfoxide ratio from that of thermal drying. In a sludge-sulfur model, the proposed treatment promoted the oxidation and decomposition of organic sulfur without noticeably affecting the inorganic sulfur. The selective oxidation process during EMI drying promotes sulfur stabilisation in dried DS, decreasing the performance and stability of DS combustion. The sulfur-containing pollutants released during the incineration of DS mainly contain H2S, followed by CH3SH and SO2. EMI drying increases the outputs of SO2 and CH3SH but decreases the outputs H2S and total sulfur compared with the outputs of thermal drying. Under the sulfur-model conditions, EMI promoted the conversion of inorganic sulfur to sulfur-containing gases (especially H2S) during incineration. In contrast, the sulfur stabilised by partial oxidation of organic sulfur in the EMI-dried DS was not easily converted to gaseous sulfur during subsequent combustion. Overall, EMI inhibits the release of sulfur during the combined drying-incineration process of DS.
Collapse
Affiliation(s)
- Mengxin Lu
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China
| | - Yongjie Xue
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China
| | - Hui Zhao
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China
| | - Xiaoshan Zhang
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China
| | - 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.
| |
Collapse
|
7
|
Hu QM, Huang YX, Zhang WY, Shao GT, Xu Y, Zhang YH, Pan Y, Mi JX. Industrial-scale extraction of high value-added kaolin from excavation waste: Demonstration from Xiamen, China. WASTE MANAGEMENT (NEW YORK, N.Y.) 2023; 163:144-153. [PMID: 37015150 DOI: 10.1016/j.wasman.2023.03.028] [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: 05/16/2022] [Revised: 02/26/2023] [Accepted: 03/21/2023] [Indexed: 06/19/2023]
Abstract
Excavation waste from the construction of subways and other underground infrastructures is mainly composed of gravel, sand and clay of minimal economic value, which commonly ends up in landfills. Although the coarse sand and gravel of the excavation waste are typically recycled on site, a large amount of the fine-grained residue must be disposed of due to the prohibition of marine land reclamation in Xiamen, China, leading to an increasingly severe shortage of landfills. In this contribution, a new strategy was successfully developed for industrial-scale extraction of high value-added kaolin from the excavation waste of Xiamen. This strategy can overcome the challenges of complex and variable chemical compositions, high iron contents, low industrial grade, and organic contaminants in the raw materials. Characterization using chemical analysis, powder X-ray diffraction, scanning electron microscopy, and infrared spectroscopy showed that the Xiamen excavation waste originated from granite weathering is mainly composed of kaolinite and quartz, along with high Fe contents and other impurities. The excavation waste was subjected to an intensive process of blunging, grinding, sieving, and classifying, as well as successive iron removal by magnetic separation. Subsequently, the extracted products meet commercial requirements, including those for high-quality kaolin with whiteness and plasticity larger than 90° and 17%, respectively. Moreover, an industrial-scale green production line with an annual treatment capacity of one million tonnes of excavation waste at the utilization rate of 100% was implemented. Hence, this work presents an effective approach for exploiting similar excavation waste around the world to promote sustainable development.
Collapse
Affiliation(s)
- Qi-Ming Hu
- Joint Laboratory of Comprehensive Utilization of Non-Metallic Mineral Resources of XYS-XMU, Department of Materials Science and Engineering, College of Materials, Xiamen University, No. 422 Siming South Road, Xiamen 361005, Fujian Province, People's Republic of China; Xiamen Xinyisheng New Materials Science & Technology Co., Ltd, No. 681 Xinmin Avenue, Xiamen 361113, Fujian Province, People's Republic of China
| | - Ya-Xi Huang
- Joint Laboratory of Comprehensive Utilization of Non-Metallic Mineral Resources of XYS-XMU, Department of Materials Science and Engineering, College of Materials, Xiamen University, No. 422 Siming South Road, Xiamen 361005, Fujian Province, People's Republic of China
| | - Wu-Yi Zhang
- Xiamen Xinyisheng New Materials Science & Technology Co., Ltd, No. 681 Xinmin Avenue, Xiamen 361113, Fujian Province, People's Republic of China
| | - Gang-Tiao Shao
- Xiamen Xinyisheng New Materials Science & Technology Co., Ltd, No. 681 Xinmin Avenue, Xiamen 361113, Fujian Province, People's Republic of China
| | - Yan Xu
- Xiamen Xinyisheng New Materials Science & Technology Co., Ltd, No. 681 Xinmin Avenue, Xiamen 361113, Fujian Province, People's Republic of China
| | - Yi-Heng Zhang
- Xiamen Xinyisheng New Materials Science & Technology Co., Ltd, No. 681 Xinmin Avenue, Xiamen 361113, Fujian Province, People's Republic of China
| | - Yuanming Pan
- Department of Geological Sciences, University of Saskatchewan, Saskatoon SK S7N 5E2, Canada
| | - Jin-Xiao Mi
- Joint Laboratory of Comprehensive Utilization of Non-Metallic Mineral Resources of XYS-XMU, Department of Materials Science and Engineering, College of Materials, Xiamen University, No. 422 Siming South Road, Xiamen 361005, Fujian Province, People's Republic of China.
| |
Collapse
|
8
|
Xu X, Zhu D, Jian Q, Wang X, Zheng X, Xue G, Liu Y, Li X, Hassan GK. Treatment of industrial ferric sludge through a facile acid-assisted hydrothermal reaction: Focusing on dry mass reduction and hydrochar recyclability performance. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 869:161879. [PMID: 36716871 DOI: 10.1016/j.scitotenv.2023.161879] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/15/2023] [Accepted: 01/24/2023] [Indexed: 06/18/2023]
Abstract
Large amounts of Fenton sludge and waste activated sludge (WAS) are mixed as ferric sludge (FS) in most industrial wastewater treatment plants. The treatment of such waste represents a challenge and quantity-dependent cost, so that a reliable way for FS waste reduction is required. In this study, we develop a facile acid-assisted hydrothermal treatment (HT) for the cost-efficient treatment of hazardous FS waste. Sulfuric acid was dosed at 0.25 mL/g dry solid (DS) to the HT process, which significantly increased the total solid mass reduction (TMR) by 25.1 % and dry mass reduction (DMR) by 104.4 %. The participation of sulfuric acid during the HT process changed the HT reaction pathway from dehydration to demethylation based on the analysis of the derivative thermogravimetric and Van Krevelen diagram. The addition of sulfuric acid improved the release of Fe from FS by 52.9 %, which contributed to the DMR. During the acid-assisted HT, Fe(III) was effectively reduced to Fe(II) within the produced hydrochar, which can be recycled for the Fenton reaction during the degradation of actual industrial wastewater such as pharmaceutical wastewater. Moreover, Sulfuric acid facilitated the generation of sulfonated hydrochar, which was efficient as an adsorbent for the complete removal of some metals such as Cu(II) - cation metal (98.8 %) and Cr(VI) - anion metal (99.9 %). This study firstly provides a novel and reliable approach for hazardous FS reduction and pointed out the recycling of hydrochar as the supplement for the Fenton reaction and adsorbents for some hazardous heavy metals.
Collapse
Affiliation(s)
- Xianbao Xu
- College of Environmental Science and Engineering, State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, 2999 North Renmin Road, Shanghai 201620, China
| | - Daan Zhu
- College of Environmental Science and Engineering, State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, 2999 North Renmin Road, Shanghai 201620, China
| | - Qiwei Jian
- School of Mechanical and Automotive Engineering, Shanghai University of Engineering Science, Shanghai 201620, China.
| | - Xiaonuan Wang
- College of Environmental Science and Engineering, State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, 2999 North Renmin Road, Shanghai 201620, China
| | - Xiaohu Zheng
- Institute of Artificial Intelligence, Donghua University, 2999 North Renmin Road, Shanghai 201620, China
| | - Gang Xue
- College of Environmental Science and Engineering, State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, 2999 North Renmin Road, Shanghai 201620, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Yanbiao Liu
- College of Environmental Science and Engineering, State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, 2999 North Renmin Road, Shanghai 201620, China
| | - Xiang Li
- College of Environmental Science and Engineering, State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, 2999 North Renmin Road, Shanghai 201620, China.
| | - Gamal Kamel Hassan
- Water Pollution Research Department, National Research Centre, 33El-Bohouth St. (Former El-Tahrir St.), Dokki, P.O. 12622, Giza, Egypt
| |
Collapse
|
9
|
Makoś-Chełstowska P. VOCs absorption from gas streams using deep eutectic solvents - A review. JOURNAL OF HAZARDOUS MATERIALS 2023; 448:130957. [PMID: 36860043 DOI: 10.1016/j.jhazmat.2023.130957] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 01/27/2023] [Accepted: 02/05/2023] [Indexed: 06/18/2023]
Abstract
Volatile organic compounds (VOCs) are one of the most severe atmospheric pollutants. They are mainly emitted into the atmosphere from anthropogenic sources such as automobile exhaust, incomplete fuel combustion, and various industrial processes. VOCs not only cause hazards to human health or the environment but also adversely affect industrial installation components due to their specific properties, i.e., corrosive and reactivity. Therefore, much attention is being paid to developing new methods for capturing VOCs from gaseous streams, i.e., air, process streams, waste streams, or gaseous fuels. Among the available technologies, absorption based on deep eutectic solvents (DES) is widely studied as a green alternative to other commercial processes. This literature review presents a critical summary of the achievements in capturing individual VOCs using DES. The types of used DES and their physicochemical properties affecting absorption efficiency, available methods for evaluating the effectiveness of new technologies, and the possibility of regeneration of DES are described. In addition, critical comments on the new gas purification methods and future perspectives are included.
Collapse
Affiliation(s)
- Patrycja Makoś-Chełstowska
- Department of Process Engineering and Chemical Technology, Faculty of Chemistry, Gdansk University of Technology, 80-233 Gdansk, Poland; EcoTech Center, Gdańsk University of Technology, 80-233 Gdańsk, Poland.
| |
Collapse
|
10
|
Zhu X, Yang X, Gao W, Zhao S, Zhang W, Yu P, Wang D. Malodorous volatile organic compounds (MVOCs) formation after dewatering of wastewater sludge: Correlation with the extracellular polymeric substances (EPS) and microbial communities. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 867:161491. [PMID: 36634527 DOI: 10.1016/j.scitotenv.2023.161491] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 12/29/2022] [Accepted: 01/05/2023] [Indexed: 06/17/2023]
Abstract
Malodorous volatile organic compounds (MVOCs) are often the key odorants in determining sludge odor character and odor impact. However, the emission characterization and generation mechanisms of MVOCs from various dewatered sludge have not been sufficiently understood partly due to the diverse and complex composition and low concentration of odorants. In this study, waste activated sludge (WAS) was collected to examine the variation of MVOC emission from sludge after different dewatering treatment in lab-scale trials. The MVOCs were measured using the electronic nose (eNose), headspace gas chromatography-coupled ion mobility spectrometry (HS-GC-IMS), and headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS). The results showed that centrifugation treatment promoted the generation of various odorous volatiles. The identified key odorants included dimethyl sulfide (DMS), dimethyl disulfide (DMDS), dimethyl trisulfide (DMTS), geosmin, and p-cresol according to their odor activity values (OAVs). The effects of the enhanced dewatering on volatile production were greater than thickening, however, the key odorants of dewatered sludge using gravity thickening varied more greatly than sludges from centrifuge thickening. The distribution of extracellular polymeric substances (EPS) and variation of microbial community showed correlations with the production of key odorants. Tryptophan-like substances in the inner layer of EPS (LB-EPS and TB-EPS) were better correlated with the key odorants. The bound EPS released by centrifugation may play the role of precursor for odorous microbial volatiles. According to the predicted functions of differential microbial genera, Desulfobulbus (Desulfobacterota), Gordonia (Actinobacteriota), and Hyphomicrobium (Proteobacteria) were associated with the production of DMS, DMDS, and DMTS, while Gordonia and Hyphomicrobium were related to p-cresol production.
Collapse
Affiliation(s)
- Xinmeng Zhu
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China; Yangtze River Delta Research Center for Eco-Environmental Sciences, Yiwu 322000, China
| | - Xiaofang Yang
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Yangtze River Delta Research Center for Eco-Environmental Sciences, Yiwu 322000, China.
| | - Wei Gao
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China; Yangtze River Delta Research Center for Eco-Environmental Sciences, Yiwu 322000, China
| | - Shan Zhao
- Research and Development Center, Beijing Drainage Group Co., Ltd, Beijing 100124, China
| | - Weijun Zhang
- Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science, School of Environmental Studies, China University of Geosciences, Wuhan 430074, Hubei, China
| | - Pingfeng Yu
- Department of Environment Engineering, Zhejiang University, Hangzhou 310058, China
| | - Dongsheng Wang
- Yangtze River Delta Research Center for Eco-Environmental Sciences, Yiwu 322000, China; Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science, School of Environmental Studies, China University of Geosciences, Wuhan 430074, Hubei, China; Department of Environment Engineering, Zhejiang University, Hangzhou 310058, China
| |
Collapse
|
11
|
Zhou A, Wang X, Yu S, Deng S, Tan H, Mikulčić H. Process design and optimization on self-sustaining pyrolysis and carbonization of municipal sewage sludge. WASTE MANAGEMENT (NEW YORK, N.Y.) 2023; 159:125-133. [PMID: 36753855 DOI: 10.1016/j.wasman.2023.01.035] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 01/19/2023] [Accepted: 01/29/2023] [Indexed: 06/18/2023]
Abstract
Pyrolysis can realize the reduction and resource utilization of municipal sewage sludge (MSS). In this paper, a self-sustaining pyrolysis process is designed for municipal sewage sludge, and the process flow is simulated by Aspen plus software. By changing the initial moisture content of sludge, moisture content after drying, pyrolysis temperature and air supply in the incinerator, the possibility of achieving energy self-balance in the system is analysed. The simulation results show that by adjusting the parameters of the system, this process can realize the energy self-balance of sludge drying and pyrolysis treatment. Considering the system's energy loss, the dry basis calorific value of sludge should not be less than 10 MJ/kg. The higher the initial moisture content of sludge, the more external energy input the system needs. It is recommended to dehydrate sludge mechanically to about 60 % before entering the system. When the pyrolysis temperature is increased, the amount of oil and gas produced by sludge pyrolysis increases, and it is easier to achieve self-balance of system energy. But the higher the pyrolysis temperature, the greater the energy consumption required. In practice, it is suggested that the pyrolysis temperature is about 400 °C. The moisture content of dried sludge has little effect on the energy self-balance of the system, and it is recommended to be about 30 %. The air supply volume of the incinerator mainly affects the flue gas outlet temperature and flue gas volume, but has little effect on the energy balance of the system.
Collapse
Affiliation(s)
- Ao Zhou
- MOE Key Laboratory of Thermo-Fluid Science and Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China
| | - Xuebin Wang
- MOE Key Laboratory of Thermo-Fluid Science and Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China.
| | - Shilin Yu
- MOE Key Laboratory of Thermo-Fluid Science and Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China
| | - Shuanghui Deng
- MOE Key Laboratory of Thermo-Fluid Science and Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China
| | - Houzhang Tan
- MOE Key Laboratory of Thermo-Fluid Science and Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China
| | - Hrvoje Mikulčić
- MOE Key Laboratory of Thermo-Fluid Science and Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China
| |
Collapse
|
12
|
Gao X, Yang F, Cheng J, Xu Z, Zang B, Li G, Xie X, Luo W. Emission of volatile sulphur compounds during swine manure composting: Source identification, odour mitigation and assessment. WASTE MANAGEMENT (NEW YORK, N.Y.) 2022; 153:129-137. [PMID: 36088860 DOI: 10.1016/j.wasman.2022.08.029] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Revised: 08/16/2022] [Accepted: 08/29/2022] [Indexed: 06/15/2023]
Abstract
This study aimed to identify the sources of volatile sulphur compounds (VSCs) and evaluate their mitigation by ferric oxide (Fe2O3) during swine manure composting. Four chemicals, including l-cysteine, l-methionine, sodium sulphite, and sodium sulphate, were further added to simulate organic and inorganic sulphur-containing substances in swine manure to track VSC sources during composting. Results show that sulphur simulants induced the emission of six common VSCs, including methyl sulphide (Me2S), dimethyl sulphide (Me2SS), carbonyl sulphide (COS), carbon disulphide (CS2), methyl mercaptan (MeSH), and ethyl mercaptan (EtSH), during swine manure composting. Of them, COS, CS2, MeSH and Me2SS were predominantly contributed by the biodegradation of methionine and cysteine, while Me2S and EtSH were dominated by the reduction of sulphite and sulphate. Further Fe2O3 addition at 1.5 % of total wet weight of composting materials immobilized elemental sulphur and inhibited sulphate reduction to reduce the emission of VSCs by 46.7-80.9 %. Furthermore, odour assessment indicated that adding Fe2O3 into composting piles significantly reduced the odour intensity level to below 4, the odour value of VSCs by 47.1-81.3 %, and thus the non-carcinogenic risk by 68.4 %.
Collapse
Affiliation(s)
- Xingzu Gao
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Feiyu Yang
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Jingwen Cheng
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Zhicheng Xu
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Bing Zang
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Guoxue Li
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Sanya Institute of China Agricultural University, China Agricultural University, Sanya 572025, China
| | - Xiaomin Xie
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China.
| | - Wenhai Luo
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Sanya Institute of China Agricultural University, China Agricultural University, Sanya 572025, China.
| |
Collapse
|
13
|
Polvara E, Gallego E, Invernizzi M, Perales JF, Sironi S. Chemical characterization of odorous emissions: A comparative performance study of different sampling methods. Talanta 2022. [DOI: 10.1016/j.talanta.2022.124110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
14
|
Ling W, Xing Y, Hong C, Zhang B, Hu J, Zhao C, Wang Y, Feng L. Methods, mechanisms, models and tail gas emissions of convective drying in sludge: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 845:157376. [PMID: 35843332 DOI: 10.1016/j.scitotenv.2022.157376] [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: 04/30/2022] [Revised: 07/10/2022] [Accepted: 07/10/2022] [Indexed: 06/15/2023]
Abstract
In tandem with the population and economic growth worldwide, the scale of wastewater treatment has been increasing each year. Thus, a large amount of sludge is being produced. If the problem of sludge treatment and disposal cannot be effectively solved, it will cause serious environmental pollution. The premise of sludge drying is that sludge is "harmless" and can be "recycled." Currently, the studies on convective drying focus on the direction of thin-layer drying, fluidized bed drying, spray drying and pneumatic drying. This paper systematically reviews the convective drying technology of sludge. First, the effects of air velocity temperature, relative humidity and particle size on the drying effect are precisely described, as well as the four different drying stages in the drying process, including preheating, constant rate drying, first falling rate drying, and second falling rate drying stages. Second, the research progress of different convective drying treatment technologies and the application of eight mathematical models of thin-layer drying in this field are elaborated. The effects of sludge shrinkage formation mechanisms and sludge viscous resistance generation during the drying process are also discussed in detail. The formation mechanism of sludge shrinkage and the effect of sludge viscosity resistance during drying are also elaborated. Finally, the main dry tail gases and restraining methods are elaborated during the drying process. This paper will provide a structured reference for the related research of sludge convective drying in the future.
Collapse
Affiliation(s)
- Wei Ling
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, China; State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 10083, China
| | - Yi Xing
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, China
| | - Chen Hong
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, China; State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 10083, China.
| | - Bo Zhang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, China
| | - Jiashuo Hu
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, China
| | - Chengwang Zhao
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, China
| | - Yijie Wang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, China
| | - Lihui Feng
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, China
| |
Collapse
|
15
|
Haider KM, Lafouge F, Carpentier Y, Houot S, Petitprez D, Loubet B, Focsa C, Ciuraru R. Chemical identification and quantification of volatile organic compounds emitted by sewage sludge. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:155948. [PMID: 35588801 DOI: 10.1016/j.scitotenv.2022.155948] [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: 03/17/2022] [Revised: 04/29/2022] [Accepted: 05/10/2022] [Indexed: 06/15/2023]
Abstract
The recycling of organic waste products (e.g. sewage sludge, SS) is currently being promoted as a substitute for mineral fertilizers for agricultural lands. The spreading of SS allows the recycling of the nutrients and organic matter it contains. SS contains various pollutants such as volatile organic compounds (VOCs) that adversely affect the ecosystem and human health through ozone production and serve as critical precursors of atmospheric secondary organic aerosols. There are very few studies quantifying the gaseous compounds emitted from SS, and those studies primarily address their odorant properties for identifying suitable odour abatement techniques. There is an urgent need for more comprehensive quantitative information on VOCs emitted from SS as aerosol precursors. In this context, an experimental study was performed on SS samples taken from a wastewater treatment plant located in France. Undigested SS (UDSS), digested SS (DSS) and SS with 30% and 60% dryness were collected from different stages of treatment sequence and analyzed using atmospheric simulation chambers coupled to proton-transfer-reaction quadrupole ion-guide time-of-flight mass spectrometer. Our study revealed that SS samples emitted a large spectrum of VOCs. 380 compounds were detected, quantified and classified into different chemical groups. The VOC emissions increased with the increase in the dryness of the sample; the highest being in SS 60%, followed by SS 30%, UDSS and DSS. OVOCs were dominant in SS 60%. The statistical analysis showed that the anaerobic digestion and the dewatering to 60% of dryness decreased the emissions of sulphuric compounds. Aromatic compounds and indoles (e.g. skatole) were emitted significantly from the UDSS. Some of these VOCs can serve as precursor gases for atmospheric aerosol formation. The experimental dataset obtained in this study provides an accurate inventory reference for the VOC emissions from SS samples and shows the impacts of the treatment on emission characteristics of VOCs.
Collapse
Affiliation(s)
- K M Haider
- Univ. Lille, CNRS, UMR 8523 - PhLAM - Physique des Lasers, Atomes et Molécules, Lille F-59000, France; INRAe, UMR 1402 ECOSYS, AgroParisTech, Université Paris-Saclay, 78850 Thiveral-Grignon, France
| | - F Lafouge
- INRAe, UMR 1402 ECOSYS, AgroParisTech, Université Paris-Saclay, 78850 Thiveral-Grignon, France
| | - Y Carpentier
- Univ. Lille, CNRS, UMR 8523 - PhLAM - Physique des Lasers, Atomes et Molécules, Lille F-59000, France
| | - S Houot
- INRAe, UMR 1402 ECOSYS, AgroParisTech, Université Paris-Saclay, 78850 Thiveral-Grignon, France
| | - D Petitprez
- Univ. Lille, CNRS, UMR 8522 - PC2A - PhysicoChimie des Processus de Combustion et de l'Atmosphère, Lille F-59000, France
| | - B Loubet
- INRAe, UMR 1402 ECOSYS, AgroParisTech, Université Paris-Saclay, 78850 Thiveral-Grignon, France
| | - C Focsa
- Univ. Lille, CNRS, UMR 8523 - PhLAM - Physique des Lasers, Atomes et Molécules, Lille F-59000, France
| | - R Ciuraru
- INRAe, UMR 1402 ECOSYS, AgroParisTech, Université Paris-Saclay, 78850 Thiveral-Grignon, France.
| |
Collapse
|
16
|
Zhu X, Yang X, Gao W, Jiao R, Zhao S, Yu J, Wang D. Effect of low-temperature thermal drying on malodorous volatile organic compounds (MVOCs) emission of wastewater sludge: The relationship with microbial communities. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 306:119423. [PMID: 35537553 DOI: 10.1016/j.envpol.2022.119423] [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: 02/20/2022] [Revised: 05/02/2022] [Accepted: 05/03/2022] [Indexed: 06/14/2023]
Abstract
Sludge treatment processes are the main source of nuisance odors in wastewater treatment plants. Apart from well-known odorants such as NH3 and H2S, malodorous volatile organic compounds (MVOCs) contribute largely to nuisance odors but are less concerned. In this work, the emission of MVOCs from wastewater sludges at different processing stages was measured, and the effects of dewatering and low-temperature thermal drying on the generation of sludge odor were investigated. The MVOCs were analyzed by olfactory measurements, headspace gas chromatography-coupled ion mobility spectrometry (HS-GC-IMS), and headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS). Low-temperature thermal drying treatment changed the odor categories and increased the odor intensity (OI) from moderate level (8-9) for raw sludges to strong (>10) for dried sludge. The odor emission capacity of MVOCs, namely the concentration of MVOCs, increased for dried sludge. The major odorants of sludge after different processes included 2-MIB, geosmin, dimethyl disulfide (DMDS), dimethyl trisulfide (DMTS), hexanal, and decanal according to their odor activity values (OAVs). The bacterial community structures showed a correlation with the key MVOC odorants. Specifically, there was a significant positive correlation between the concentration of key odorants and the relative abundance of the phyla of Actinobacteria and Chloroflexi. Thus, low-temperature thermal drying had a significant effect on odor formation by acting on the microbial community of sludge.
Collapse
Affiliation(s)
- Xinmeng Zhu
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Yangtze River Delta Research Center for Eco-Environmental Sciences, Yiwu, 322000, China
| | - Xiaofang Yang
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; Yangtze River Delta Research Center for Eco-Environmental Sciences, Yiwu, 322000, China.
| | - Wei Gao
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Yangtze River Delta Research Center for Eco-Environmental Sciences, Yiwu, 322000, China
| | - Ruyuan Jiao
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; Yangtze River Delta Research Center for Eco-Environmental Sciences, Yiwu, 322000, China
| | - Shan Zhao
- Research and Development Center, Beijing Drainage Group Co., Ltd, Beijing, 100124, China
| | - Jianwei Yu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Dongsheng Wang
- Yangtze River Delta Research Center for Eco-Environmental Sciences, Yiwu, 322000, China; Department of Environment Engineering, Zhejiang University, Hangzhou, 310058, China
| |
Collapse
|
17
|
Lu Y, Liu C, Mei C, Sun J, Lee J, Wu Q, Hubbe MA, Li MC. Recent advances in metal organic framework and cellulose nanomaterial composites. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2022.214496] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
18
|
Enhanced Sewage Sludge Drying with a Modified Solar Greenhouse. CLEAN TECHNOLOGIES 2022. [DOI: 10.3390/cleantechnol4020025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This work reports the results obtained with an innovative configuration of a closed-static solar greenhouse for sludge drying. The novelty of the solar greenhouse configuration consisted in using a forced ventilation system to provide hot air for sludge drying and the utilization of solar irradiation for energy supply. Wet sewage sludge (97% humidity) was successfully dried up to a residual humidity close to 5% after 25 days during wintertime. The increase of the airflow rate supplied under the sludge bed improved the sludge drying rate. Moreover, the fraction of volatile suspended solids decreased from 70% to 41% after 13 days, indicating that air supply promoted the simultaneous stabilization of the sludge as a side-effect to the drying process. Overall, the specific energy consumption per ton of evaporated water was estimated to approximately 450 kWh/t, resulting in about 55% of energy demand lower than a conventional thermal drying system, while using only free solar energy. The achieved high weight reduction of up to 99% implies a noticeable reduction of the excess sludge handling costs, indicating that solar greenhouse drying is a highly interesting opportunity for sludge drying in medium-small sized WWTPs.
Collapse
|