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Banu JR, Kumar G, Gunasekaran M. Augmentation in polyhydroxybutyrate and biogas production from waste activated sludge through mild sonication induced thermo-fenton disintegration. BIORESOURCE TECHNOLOGY 2023; 369:128376. [PMID: 36414138 DOI: 10.1016/j.biortech.2022.128376] [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: 09/06/2022] [Revised: 11/17/2022] [Accepted: 11/18/2022] [Indexed: 06/16/2023]
Abstract
In this study, an innovative approach was developed to enhance the hydrolysis through phase-separated pretreatment by removing exopolymeric substances via mild sonication followed by thermo-Fenton disintegration. The exopolymeric substances fragmentation was enhanced at the sonic specific energy input of 2.58 kJ/kg total solids. After exopolymeric substance removal, the disintegration of biomass by thermo-Fenton yield the solubilization of 29.8 % at Fe2+:H2O2 dosage and temperature of 0.009:0.036 g/g suspended solids and 80 °C as compared to thermo-Fenton alone disintegration. The polyhydroxybutyrate content of 93.1 % was accumulated by Bacillus aryabhattai at the optimum time of 42 h, while providing 70 % (v/v) pre-treated supernatant as a carbon source under nutrient-limiting condition. Moreover, the biogas generation of 0.187 L/g chemical oxygen demand was achieved using settled pretreated sludge. The pretreated sludge sample thus served as a carbon source for polyhydroxybutyrate producers as well as substrate for biogas production.
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Affiliation(s)
- J Rajesh Banu
- Department of Biotechnology, Central University of Tamil Nadu, Neelakudi, Thiruvarur 610005, India
| | - Gopalakrishnan Kumar
- School of Civil and Environmental Engineering, Yonsei University, Seoul 03722, Republic of Korea; Institute of Chemistry, Bioscience and Environmental Engineering, Faculty of Science and Technology, University of Stavanger, Stavanger, Norway
| | - M Gunasekaran
- Department of Physics, Anna University Regional Campus, Tirunelveli, TamilNadu 627007, India.
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2
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Zhang Y, Li T, Tian J, Zhang H, Li F, Pei J. Enhanced dewaterability of waste activated sludge by UV assisted ZVI-PDS oxidation. J Environ Sci (China) 2022; 113:152-164. [PMID: 34963525 DOI: 10.1016/j.jes.2021.06.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Revised: 06/07/2021] [Accepted: 06/08/2021] [Indexed: 06/14/2023]
Abstract
Ultraviolet (UV) assisted zero-valent iron (ZVI)-activated sodium persulfate (PDS) oxidation (UV-ZVI-PDS) was used to treat waste activated sludge (WAS) in this study. The dewaterability performance and mechanism of WAS dewatering were analyzed. The results showed that UV-ZVI-PDS can obtain better sludge dewatering performance in a wide pH range (2.0-8.0). When the molar ratio of ZVI/PDS was 0.6, UV was 254nm, PDS dosage was 200 mg/g TS (total solid), pH was 6.54, reaction time was 20 min, the CST (capillary suction time) and SRF (specific resistance to filtration) were decreased by 64.0% and 78.2%, respectively. The molar ratio of ZVI/PDS used in this paper is much lower than that of literatures, and the contents of total Fe and Fe2+ in sludge supernatant remained at a low level, as 3.7 mg/L and 0.0 mg/L. The analysis of extracellular polymeric substances (EPS), scanning electron microscope (SEM) and particle size distribution showed that the EPS could be effectively destroyed by UV-ZVI-PDS, the sludge flocs broken down into smaller particles, cracks and holes appeared, and then the bound water was released. At the same time, the highly hydrophilic tightly bound-EPS (TB-EPS) were converted into loosely bound EPS (LB-EPS) and soluble EPS (S-EPS). During sludge pretreated by UV-ZVI-PDS, positively charged ions, such as Fe2+, Fe3+ and H+, produced in the reaction system could reduce the electronegativity of sludge surface, promote sludge particles aggregation, and then enhanced the sludge dewaterability.
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Affiliation(s)
- Yanping Zhang
- School of Civil Engineering and Transportation, Hebei University of Technology, Tianjin 300401, China.
| | - Tiantian Li
- School of Civil Engineering and Transportation, Hebei University of Technology, Tianjin 300401, China
| | - Jiayu Tian
- School of Civil Engineering and Transportation, Hebei University of Technology, Tianjin 300401, China
| | - Huichun Zhang
- Department of Civil and Environmental Engineering, Case Western Reserve University, Cleveland, OH 44106, USA.
| | - Fen Li
- College of Chemical and Environmental Engineering, Harbin University of Science and Technology, Harbin 150000, China
| | - Jiahua Pei
- School of Civil Engineering and Transportation, Hebei University of Technology, Tianjin 300401, China
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Gao S, Wang Y, Zhang D, Fan X, Guo Y, Li E, Zheng H. Insight to peroxone-Fe(III) joint conditioning-horizontal electro-dewatering process on water reduction in activated sludge: Performance and mechanisms. JOURNAL OF HAZARDOUS MATERIALS 2021; 402:123441. [PMID: 32688188 DOI: 10.1016/j.jhazmat.2020.123441] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 06/11/2020] [Accepted: 07/06/2020] [Indexed: 06/11/2023]
Abstract
Peroxone disintegration-Fe(III) coagulation (peroxone-Fe(III)) joint conditioning was proposed to enhance the horizontal electro-dewatering (HED) effect of activated sludge (AS). Operating parameters were optimized and the evolutions of AS physicochemical properties, water fractions distribution, organic matter, extracellular polymeric substance (EPS) key components, functional groups, and protein secondary structures during the process were identified. Under the optimized joint conditioning parameters, dewatered AS achieved a final water content of 84.88 ± 0.17% and its bound water content (BWC) was decreased by 1.88 ± 0.28 g/g dry solid. During peroxone pretreatment, the yielded HO decreased the AS floc size, disintegrated the EPS network structure and cell wall, released the bound water, and extracted proteins, polysaccharides, and humic acid-like materials. Furthermore, soluble microbial byproduct-like materials (SMBP) in the EPS layers and tyrosine in tightly bound EPS significantly increased. Protein structures were destroyed, decreasing their water affinity. Subsequent Fe(III) addition re-coagulated broken flocs fragments and EPS fractions, built water flow channels, removed tyrosine and SMBP, and reduced α-helix percentage in slime, facilitating AS dewatering. After joint conditioning, the bound water and intracellular substances were further released by HED. Therefore, the peroxone-Fe(III)-HED process exhibited an excellent performance in AS water reduction.
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Affiliation(s)
- Shihui Gao
- College of Environmental Science and Engineering, Beijing Key Lab for Source Control Technology of Water Pollution, Beijing Forestry University, Beijing, 100083, China
| | - Yili Wang
- College of Environmental Science and Engineering, Beijing Key Lab for Source Control Technology of Water Pollution, Beijing Forestry University, Beijing, 100083, China.
| | - Daxin Zhang
- College of Environmental Science and Engineering, Beijing Key Lab for Source Control Technology of Water Pollution, Beijing Forestry University, Beijing, 100083, China
| | - Xiaoyang Fan
- College of Environmental Science and Engineering, Beijing Key Lab for Source Control Technology of Water Pollution, Beijing Forestry University, Beijing, 100083, China
| | - Yajie Guo
- College of Environmental Science and Engineering, Beijing Key Lab for Source Control Technology of Water Pollution, Beijing Forestry University, Beijing, 100083, China
| | - Enrui Li
- College of Environmental Science and Engineering, Beijing Key Lab for Source Control Technology of Water Pollution, Beijing Forestry University, Beijing, 100083, China
| | - Huaili Zheng
- Key Laboratory of the Three Gorges Reservoir Regions Eco-Environment, State Ministry of Education, Chongqing University, Chongqing, 400045, China
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Xu Q, Huang QS, Wei W, Sun J, Dai X, Ni BJ. Improving the treatment of waste activated sludge using calcium peroxide. WATER RESEARCH 2020; 187:116440. [PMID: 32980604 DOI: 10.1016/j.watres.2020.116440] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 09/16/2020] [Accepted: 09/19/2020] [Indexed: 06/11/2023]
Abstract
The treatment and disposal of waste activated sludge (WAS) has become one of the major challenges for the wastewater treatment plants (WWTPs) due to large output, high treatment costs and enriched substantial emerging contaminants (ECs). Therefore, reducing sludge volume, recovering energy and resource from WAS, and removing ECs and decreasing environmental risk have gained increasing attentions. Calcium peroxide (CaO2), a versatile and safe peroxide, has been widely applied in terms of WAS treatment including sludge dewatering, anaerobic sludge digestion and anaerobic sludge fermentation due to its specific properties such as generating free radicals and alkali, etc., providing supports for sludge reduction, recycling, and risk mitigation. This review outlines comprehensively the recent progresses and breakthroughs of CaO2 in the fields of sludge treatment. In particular, the relevant mechanisms of CaO2 enhancing WAS dewaterability, methane production from anaerobic digestion, short-chain fatty acids (SCFA) and hydrogen production from anaerobic fermentation, and the removal of ECs in WAS and role of experiment parameters are systematically elucidated and discussed, respectively. Finally, the knowledge gaps and opportunities in CaO2-based sludge treatment technologies that need to be focused in the future are prospected. The review presented can supply a theoretical basis and technical reference for the application of CaO2 for improving the treatment of WAS.
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Affiliation(s)
- Qiuxiang Xu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, P.R. China.
| | - Qi-Su Huang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Wei Wei
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Jing Sun
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, P.R. China
| | - Xiaohu Dai
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, P.R. China
| | - Bing-Jie Ni
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, P.R. China.
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Hu J, Li Z, Zhang A, Mao S, Jenkinson IR, Tao W. Using a strong chemical oxidant, potassium ferrate (K 2FeO 4), in waste activated sludge treatment: A review. ENVIRONMENTAL RESEARCH 2020; 188:109764. [PMID: 32531522 DOI: 10.1016/j.envres.2020.109764] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 05/28/2020] [Accepted: 05/28/2020] [Indexed: 06/11/2023]
Abstract
The ever-increasing production of waste activated sludge (WAS) has become a widespread problem to sewage treatment plants around the world. Among the multitudinous sludge treatment methods, chemical oxidation is considered as an excellent technology with both high efficiency and low investment cost. As an eco-friendly oxidant, potassium ferrate (PF) has attracted great attention in sludge treatment over the past decade. The applications of PF have demonstrated advantages in: (1) sludge dewatering; (2) minimization; (3) anaerobic fermentation; (4) removal of pollutants. This review summarizes recent work on the effects of PF on these four aspects of facilitating sludge disposal. Meanwhile, the underlying mechanisms for the diverse applications of PF on sludge treatment are analyzed. Furthermore, the shortages and knowledge gaps on current PF oxidizing methods are discussed, and directions for further research to simultaneously enhance treatment efficiency and reduce processing cost are suggested as well.
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Affiliation(s)
- Jiawei Hu
- State Key Laboratory of Pollution Control and Resource Reuse, International Joint Research Center for Sustainable Urban Water System, College of Environmental Science & Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, PR China; UN Environment-Tongji Institute of Environment for Sustainable Development, Siping Road, Shanghai, 200092, PR China
| | - Zhuo Li
- State Key Laboratory of Pollution Control and Resource Reuse, International Joint Research Center for Sustainable Urban Water System, College of Environmental Science & Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, PR China.
| | - Ai Zhang
- College of Environmental Science and Engineering, Donghua University, 2999 North Renmin Road, Shanghai, 201620, China
| | - Shun Mao
- State Key Laboratory of Pollution Control and Resource Reuse, International Joint Research Center for Sustainable Urban Water System, College of Environmental Science & Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, PR China
| | - Ian R Jenkinson
- Agency for Consultation and Research in Oceanography, 19320, La Roche Canillac, France
| | - Wenquan Tao
- State Key Laboratory of Pollution Control and Resource Reuse, International Joint Research Center for Sustainable Urban Water System, College of Environmental Science & Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, PR China
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Wang D, He D, Liu X, Xu Q, Yang Q, Li X, Liu Y, Wang Q, Ni BJ, Li H. The underlying mechanism of calcium peroxide pretreatment enhancing methane production from anaerobic digestion of waste activated sludge. WATER RESEARCH 2019; 164:114934. [PMID: 31394464 DOI: 10.1016/j.watres.2019.114934] [Citation(s) in RCA: 108] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Revised: 07/23/2019] [Accepted: 07/29/2019] [Indexed: 05/21/2023]
Abstract
Recent investigations verified that calcium peroxide (CaO2) could be used to pretreat waste activated sludge to promote methane yield from anaerobic digestion. However, the underlying mechanism of how CaO2 pretreatment promotes methane production is unclear. This work therefore aims to provide insights into such systems. Experimental results showed that with an increase of CaO2 dosage from 0 to 0.14 g/g VSS (volatile suspended solids) the methane yield increased linearly from 146.3 to 215.9 mL/g VSS. Further increases of CaO2 resulted in decreases in methane yield. CaO2 pretreatment promoted the disintegration of sludge and the degradation of sludge recalcitrant organics (especially humus and lignocellulose), thereby providing more substrates for subsequent methane production. Ultraviolet absorption spectroscopy indicated that CaO2 enhanced the cleavage of unsaturated conjugated bonds and reduced the aromaticity of humus and lignocellulose. Fourier transform infrared spectroscopy showed that CaO2 changed the structures and functional groups of humus and lignocellulose, making them transform to be biodegradable. GC/MS analyses exhibited that the degradation products of humus and lignocellulose included several types of small molecular organics such as ester-like, acid-like, and alcohol-like substances. Further investigation demonstrated that substantial methane could be produced from these degradation products. It was also found that the presence of recalcitrant organics was detrimental to anaerobes relevant to anaerobic digestion, and the degradation of such recalcitrant organics mitigated their inhibitions to the anaerobes. Model-based analysis suggested that CaO2 pretreatment increased the maximum methane yield and methane production rate, which were consistent with the analysis above.
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Affiliation(s)
- Dongbo Wang
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China.
| | - Dandan He
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China
| | - Xuran Liu
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China
| | - Qiuxiang Xu
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China
| | - Qi Yang
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China
| | - Xiaoming Li
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, PR China
| | - Yiwen Liu
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia
| | - Qilin Wang
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia
| | - Bing-Jie Ni
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia
| | - Hailong Li
- School of Energy Science and Engineering, Central South University, Changsha, 410083, PR China
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What Advanced Treatments Can Be Used to Minimize the Production of Sewage Sludge in WWTPs? APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9132650] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Similar to other types of waste, sewage sludge (SS) must be minimized, not only to respect the European Directive 2018/851 on waste, but also because the cost of sludge management is approximately 50% of the total running costs of a wastewater treatment plant (WWTP). Usually, minimization technologies can involve sewage sludge production with three different strategies: (i) adopting a process in the water line that reduces the production of sludge; (ii) reducing the water content (dewatering processes) or (iii) reducing the fraction of volatile solids (stabilization). This review, based on more than 130 papers, aims to provide essential information on the process, such as the advantages, the drawbacks and the results of their application. Moreover, significant information on the technologies still under development is provided. Finally, this review reports a discussion on the impact of the application of the proposed processes in the sludge line on a WWTP with a capacity exceeding 100,000 population equivalent (PE).
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Heng GC, Isa MH, Lim JW, Ho YC, Zinatizadeh AAL. Enhancement of anaerobic digestibility of waste activated sludge using photo-Fenton pretreatment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:27113-27124. [PMID: 28963706 DOI: 10.1007/s11356-017-0287-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 09/20/2017] [Indexed: 06/07/2023]
Abstract
Biological treatments, such as activated sludge process, are common methods to treat municipal and industrial wastewaters. However, they produce huge amounts of waste activated sludge (WAS). The excess sludge treatment and disposal are a challenge for wastewater treatment plants due to economic, environmental, and regulatory factors. In this study, photo-Fenton pretreatment (oxidation using hydrogen peroxide and iron catalyst aided with UV light) was optimized using response surface methodology (RSM) and central composite design (CCD) to determine the effects of three operating parameters (H2O2 dosage, H2O2/Fe2+ molar ratio, and irradiation time) on disintegration and dewaterability of WAS. MLVSS removal, capillary suction time (CST) reduction, sCOD, and EPS were obtained as 70%, 25%, 12,000 mg/L, and 500 mg/L, respectively, at the optimal conditions, i.e., 725 g H2O2/kg TS, H2O2/Fe2+ molar ratio 80, and irradiation time 40 min. Two batch-fed completely mixed mesophilic anaerobic digesters were then operated at 15-day solid retention time (SRT) and 37 ± 0.5 °C to compare the digestibility of untreated and photo-Fenton pretreated sludge in terms of volatile solids (VS) reduction, COD removal, and biogas production at steady-state operations. Photo-Fenton pretreatment followed by anaerobic digestion of WAS was very effective and yielded 75.7% total VS reduction, 81.5% COD removal, and 0.29-0.31 m3/kg VSfed·d biogas production rate, compared to 40.7% total VS solid reduction, 54.7% COD removal, and 0.12-0.17 m3/kg VSfed·d biogas production rate for control. Thus, photo-Fenton can be a useful pretreatment step in sludge management.
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Affiliation(s)
- Gan Chin Heng
- Department of Civil and Environmental Engineering, Universiti Teknologi PETRONAS, 32610, Bandar Seri Iskandar, Perak, Malaysia
| | - Mohamed Hasnain Isa
- Department of Civil and Environmental Engineering, Universiti Teknologi PETRONAS, 32610, Bandar Seri Iskandar, Perak, Malaysia.
| | - Jun-Wei Lim
- Department of Fundamental and Applied Sciences, Universiti Teknologi PETRONAS, 32610, Bandar Seri Iskandar, Perak, Malaysia
| | - Yeek-Chia Ho
- Department of Civil and Environmental Engineering, Universiti Teknologi PETRONAS, 32610, Bandar Seri Iskandar, Perak, Malaysia
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Li Y, Wang J, Zhang A, Wang L. Enhancing the quantity and quality of short-chain fatty acids production from waste activated sludge using CaO2 as an additive. WATER RESEARCH 2015; 83:84-93. [PMID: 26141424 DOI: 10.1016/j.watres.2015.06.021] [Citation(s) in RCA: 115] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 06/11/2015] [Accepted: 06/12/2015] [Indexed: 05/25/2023]
Abstract
The effect of calcium peroxide (CaO2) addition on anaerobic fermentation of waste activated sludge (WAS) was investigated. The lab-scale experiments were conducted at 35 °C with CaO2 doses ranging from 0.05 to 0.3 g/g VSS. The performances of hydrolysis and acidification of WAS were significantly enhanced by CaO2 addition, whereas the production of methane was inhibited. Maximum total short-chain fatty acids (TSCFA) production (284 mg COD/g VSS) occurred at a CaO2 dose of 0.2 g/g VSS and fermentation time of 7 d, which was 3.9 times higher than the control tests. Further, CaO2 addition led to the conversion of other SCFAs to acetic acid. Acetic acid comprised 60.2% of TSCFA with the addition of 0.2 g CaO2/g VSS compared with 45.1% in the control tests. The mechanism of improved SCFAs generation was analyzed from the view of both chemical and biological effects. Chemical effect facilitated the disintegration of WAS, and improved the activities of both hydrolytic enzymes and acid-forming enzymes. Illumina MiSeq sequencing analysis revealed that bacteria within phylum Firmicutes increased significantly due to CaO2 addition, which played an important role in the hydrolysis and acidification of WAS. In addition, CaO2 oxidized most refractory organic contaminants, which were difficult to biodegrade under the ordinary anaerobic condition. Hydroxyl radicals were the most abundant reactive oxygen species released by CaO2, which played a key role in the removal of refractory organic compounds. We developed a promising technology to produce a valuable carbon source from WAS.
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Affiliation(s)
- Yongmei Li
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
| | - Jie Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Ai Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Lin Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
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Feki E, Khoufi S, Loukil S, Sayadi S. Improvement of anaerobic digestion of waste-activated sludge by using H₂O₂ oxidation, electrolysis, electro-oxidation and thermo-alkaline pretreatments. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:14717-14726. [PMID: 25982985 DOI: 10.1007/s11356-015-4677-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 05/07/2015] [Indexed: 06/04/2023]
Abstract
Disintegration of municipal waste-activated sludge (WAS) is regarded as a prerequisite of the anaerobic digestion process to reduce sludge volume and improve biogas yield. Pretreatment of WAS using thermo-alkaline (TA), H2O2 oxidation, electrolysis and electro-oxidation (EO) processes were investigated and compared in term of COD solubilization and biogas production. For each pretreatment, the influences of different operational variables were studied in detail. At optimum conditions, EO gave the maximum COD solubilization (28 %). The effects of pretreatments under the optimum conditions on anaerobic digestion were experienced with biochemical methane potential assay. Significant increases in biogas yield up to 78 and 40 % were observed respectively in the EO and TA pretreated samples compared to raw sludge. Results clearly revealed that the application of EO is a significant alternative method for the improvement of WAS anaerobic digestion.
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Affiliation(s)
- Emna Feki
- Environmental Bioprocess Laboratory, Centre of Biotechnology of Sfax, BP 1177, 3018, Sfax, Tunisia
| | - Sonia Khoufi
- Environmental Bioprocess Laboratory, Centre of Biotechnology of Sfax, BP 1177, 3018, Sfax, Tunisia.
| | - Slim Loukil
- Environmental Bioprocess Laboratory, Centre of Biotechnology of Sfax, BP 1177, 3018, Sfax, Tunisia
| | - Sami Sayadi
- Environmental Bioprocess Laboratory, Centre of Biotechnology of Sfax, BP 1177, 3018, Sfax, Tunisia
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12
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Zhang A, Li Y. Removal of phenolic endocrine disrupting compounds from waste activated sludge using UV, H2O2, and UV/H2O2 oxidation processes: effects of reaction conditions and sludge matrix. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 493:307-23. [PMID: 24951888 DOI: 10.1016/j.scitotenv.2014.05.149] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 04/25/2014] [Accepted: 05/31/2014] [Indexed: 05/20/2023]
Abstract
Removal of six phenolic endocrine disrupting compounds (EDCs) (estrone, 17β-estradiol, 17α-ethinylestradiol, estriol, bisphenol A, and 4-nonylphenols) from waste activated sludge (WAS) was investigated using ultraviolet light (UV), hydrogen peroxide (H2O2), and the combined UV/H2O2 processes. Effects of initial EDC concentration, H2O2 dosage, and pH value were investigated. Particularly, the effects of 11 metal ions and humic acid (HA) contained in a sludge matrix on EDC degradation were evaluated. A pseudo-first-order kinetic model was used to describe the EDC degradation during UV, H2O2, and UV/H2O2 treatments of WAS. The results showed that the degradation of the 6 EDCs during all the three oxidation processes fitted well with pseudo-first-order kinetics. Compared with the sole UV irradiation or H2O2 oxidation process, UV/H2O2 treatment was much more effective for both EDC degradation and WAS solubilization. Under their optimal conditions, the EDC degradation rate constants during UV/H2O2 oxidation were 45-197 times greater than those during UV irradiation and 11-53 times greater than those during H2O2 oxidation. High dosage of H2O2 and low pH were favorable for the degradation of EDCs. Under the conditions of pH = 3, UV wavelength = 253.7 nm, UV fluence rate = 0.069 mW cm(-2), and H2O2 dosage = 0.5 mol L(-1), the removal efficiencies of E1, E2, EE2, E3, BPA, and NP in 2 min were 97%, 92%, 95%, 94%, 89%, and 67%, respectively. The hydroxyl radical (OH) was proved to take the most important role for the removal of EDCs. Metal ions in sludge could facilitate the removal of EDCs during UV/H2O2 oxidation. Fe, Ag, and Cu ions had more obvious effects compared with other metal ions. The overall role of HA was dependent on the balance between its competition as organics and its catalysis/photosensitization effects. These indicate that the sludge matrix plays an important role in the degradation of EDCs.
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Affiliation(s)
- Ai Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Yongmei Li
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
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Zhou X, Jiang G, Wang Q, Yuan Z. A review on sludge conditioning by sludge pre-treatment with a focus on advanced oxidation. RSC Adv 2014. [DOI: 10.1039/c4ra07235a] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The production of excess sludge by biological wastewater treatment processes has been a serious issue for the operation of wastewater treatment plants (WWTP) on both the economic and environmental sides.
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Affiliation(s)
- Xu Zhou
- Advanced Water Management Centre
- The University of Queensland
- St. Lucia, Australia
| | - Guangming Jiang
- Advanced Water Management Centre
- The University of Queensland
- St. Lucia, Australia
| | - Qilin Wang
- Advanced Water Management Centre
- The University of Queensland
- St. Lucia, Australia
| | - Zhiguo Yuan
- Advanced Water Management Centre
- The University of Queensland
- St. Lucia, Australia
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Alizadeh Fard M, Aminzadeh B, Taheri M, Farhadi S, Maghsoodi M. MBR excess sludge reduction by combination of electrocoagulation and Fenton oxidation processes. Sep Purif Technol 2013. [DOI: 10.1016/j.seppur.2013.10.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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15
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Liu C, Yang Y, Wang Q, Kim M, Zhu Q, Li D, Zhang Z. Photocatalytic degradation of waste activated sludge using a circulating bed photocatalytic reactor for improving biohydrogen production. BIORESOURCE TECHNOLOGY 2012; 125:30-36. [PMID: 23023234 DOI: 10.1016/j.biortech.2012.08.139] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Revised: 08/30/2012] [Accepted: 08/30/2012] [Indexed: 06/01/2023]
Abstract
In this study, a sloping trough circulating bed photocatalytic reactor (STCBPR) was developed to degrade waste activated sludge (WAS). Effects of the four factors (shape of trough, circulating speed, TiO(2) dosage and dilution multiple of WAS) on the photocatalytic degradation of WAS were examined. Under the optimum conditions, 45% of the chemical oxygen demand (COD) removal and 47% of the volatile solids (VS) removal were achieved in 7.5-fold dilution after reaction for 8h. Moreover, the WAS was pretreated by STCBPR and then fermented to produce hydrogen. The result showed that the cumulative hydrogen production from photocatalysis pretreated WAS was 3.6 times higher than that from UV-light pretreated WAS, and 17 times higher than that from raw WAS. Therefore, it could be confirmed that the STCBPR has higher photocatalytic degradation efficiency for WAS, and photocatalytic pretreatment could enhance the biohydrogen production.
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Affiliation(s)
- Chunguang Liu
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
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16
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Pham TTH, Brar SK, Tyagi RD, Surampalli RY. Optimization of Fenton oxidation pre-treatment for B. thuringiensis - based production of value added products from wastewater sludge. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2010; 91:1657-1664. [PMID: 20381232 DOI: 10.1016/j.jenvman.2010.03.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2009] [Revised: 02/23/2010] [Accepted: 03/09/2010] [Indexed: 05/28/2023]
Abstract
Fenton oxidation pretreatment was investigated for enhancement of biodegradability of wastewater sludge (WWS) which was subsequently used as substrate for the production of value- added products. The Response surface method with fractional factorial and central composite designs was applied to determine the effects of Fenton parameters on solubilization and biodegradability of sludge and the optimization of the Fenton process. Maximum solubilization and biodegradability were obtained as 70% and 74%, respectively at the optimal conditions: 0.01 ml H(2)O(2)/g SS, 150 [H(2)O(2)](0)/[Fe(2+)](0), 25 g/L TS, at 25 degrees C and 60 min duration. Further, these optimal conditions were tested for the production of a value added product, Bacillus thuringiensis (Bt) which is being used as a biopesticide in the agriculture and forestry sector. It was observed that Bt growth using Fenton oxidized sludge as a substrate was improved with a maximum total cell count of 1.63 x 10(9)CFU ml(-1) and 96% sporulation after 48 h of fermentation. The results were also tested against ultrasonication treatment and the total cell count was found to be 4.08 x 10(8)CFU ml(-1) with a sporulation of 90%. Hence, classic Fenton oxidation was demonstrated to be a rather more promising chemical pre-treatment for Bt - based biopesticide production using WWS when compared to ultrasonication as a physical pre-treatment.
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Affiliation(s)
- T T H Pham
- INRS-ETE, Université du Québec, 490, Rue de Couronne, Québec G1K 9A9, Canada
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17
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Park CH, Bae YS, Han GB. Implementation of an excess sludge reduction step in an activated sludge process. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2010; 45:709-718. [PMID: 20390919 DOI: 10.1080/10934521003648925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
In this study, excess sewage sludge reduction resulting from the modification of an activated sludge process by incorporation of an excess sludge digesting reactor (ESDR) was examined. The ESDR was coupled to the sludge return line, and enhanced the solubilization of cell mass under thermophilic aerobic conditions. The decrease in the level of total suspended solids (TSS) observed in the reference ESDR (without thermophilic microbial inoculation) was 13.76% whereas a TSS decrease of 32.09% was achieved by the test ESDR (with thermophiles), thus showing microbial enhancement of solubilization of 18.33% over a test period of 48 h. The average excess sludge solubilization ratios (beta values) of TSS were 51.17% and 41.56% in two distinct protocols varying in operative parameters. The calculated excess sludge reduction ratio was 49.60% with a sludge recirculation ratio of 2, but increased to 68.97% when the sludge recirculation ratio rose to 3. The sludge volume indexes (SVIs) for the control and test processes were 68.4 and 57.0 respectively, indicating the absence of any negative effect of the modification on sludge settling characteristics. Effluent water quality satisfied national legislative requirements.
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Affiliation(s)
- Chul-Hwi Park
- Department of Environmental Engineering, University of Seoul, Seoul, Republic of Korea
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Aragón C, Quiroga JM, Coello MD. Comparison of four chemical uncouplers for excess sludge reduction. ENVIRONMENTAL TECHNOLOGY 2009; 30:707-714. [PMID: 19705608 DOI: 10.1080/09593330902894372] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A substantial part of the operating costs of wastewater treatment plants (WWTP) is associated with the management and treatment of the excess sludge generated during the treatment process. Different strategies have been applied for excess sludge reduction, such as the oxic-settling-anaerobic process, the high dissolved oxygen process, the uncoupler-containing activated sludge process, the ozonation-combined activated sludge process, control of sludge retention time and biodegradation of sludge in a membrane-assisted reactor. Chemical uncouplers have been shown to reduce excess sludge production, disassociating the energy coupling between catabolism and anabolism. These metabolic uncouplers may be organic compounds, such as 2,4-dinitrophenol (2,4-DNP) or 3,3',4',5-tetrachlorosalicylanilide (TCS), or heavy metals. In this paper, four different chemicals (2,4-DNP, TCS, copper (Cu) and zinc (Zn)) were chosen for short-term tests for studying their ability to reduce sludge yield (Y(x/s)) and, consequently, their potential for reducing excess sludge production. According to the results obtained, only TCS seems to be very effective in reducing sludge production from the activated sludge process. Compared with the control test, Y(x/s) can be reduced by over 30% at 0.8 mg/l TCS. It was also found that the substrate removal capability was not adversely affected by the presence of TCS. Furthermore, an increase in the microbial activity of the system was observed.
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Affiliation(s)
- C Aragón
- Centre for New Water Technologies (CENTA), Isla de la Cartuja, Seville, Spain
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