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Wang L, Zhou J, Jia Q, Ma X, Zhao Y, Gong L, Zhang H. Anaerobic digestion of hydrothermally pretreated dewatered sewage sludge: effects of process conditions on methane production and the fate of phosphorus. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:66767-66780. [PMID: 37099108 DOI: 10.1007/s11356-023-26990-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 04/09/2023] [Indexed: 05/25/2023]
Abstract
The hydrothermal pretreatment (HTP) characteristics and the fate of phosphorus (P) and anaerobic digestion (AD) performance of dewatered sewage sludge (DSS) were investigated at different hydrothermal conditions. The maximum methane yield reached 241 mL CH4/g COD when the hydrothermal conditions were 200 °C-2 h-10% (A4), and the yield was 78.28% higher than that without pretreatment (A0) and 29.62% higher than that of the initial hydrothermal conditions (A1, 140 °C-1 h-5%). Proteins, polysaccharides, and volatile fatty acids (VFAs) were the main hydrothermal products of DSS. 3D-EEM analysis revealed that tyrosine, tryptophan proteins, and fulvic acids decreased after HTP, but the content of humic acid-like substances increased, and this phenomenon was more noticeable after AD. Solid-organic P was converted into liquid-P during the hydrothermal process, and nonapatite inorganic P was converted into organic P during AD. All samples achieved positive energy balance, and the energy balance of A4 was 10.50 kJ/g VS. Microbial analysis showed that the composition of the anaerobic microbial degradation community changed as the sludge organic composition was altered. Results showed that the HTP improved the anaerobic digestion of DSS.
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Affiliation(s)
- Luyu Wang
- School of Environmental Engineering, Faculty of Environmental and Safety Engineering, Qingdao University of Science and Technology, 53, Zhengzhou Road, Qingdao, 266042, Shandong Province, China
| | - Jun Zhou
- School of Environmental Engineering, Faculty of Environmental and Safety Engineering, Qingdao University of Science and Technology, 53, Zhengzhou Road, Qingdao, 266042, Shandong Province, China
| | - Qinwei Jia
- School of Environmental Engineering, Faculty of Environmental and Safety Engineering, Qingdao University of Science and Technology, 53, Zhengzhou Road, Qingdao, 266042, Shandong Province, China
| | - Xiaofan Ma
- School of Environmental Engineering, Faculty of Environmental and Safety Engineering, Qingdao University of Science and Technology, 53, Zhengzhou Road, Qingdao, 266042, Shandong Province, China
| | - Yuhang Zhao
- School of Environmental Engineering, Faculty of Environmental and Safety Engineering, Qingdao University of Science and Technology, 53, Zhengzhou Road, Qingdao, 266042, Shandong Province, China
| | - Lei Gong
- School of Environmental Engineering, Faculty of Environmental and Safety Engineering, Qingdao University of Science and Technology, 53, Zhengzhou Road, Qingdao, 266042, Shandong Province, China.
| | - Haonan Zhang
- School of Environmental Engineering, Faculty of Environmental and Safety Engineering, Qingdao University of Science and Technology, 53, Zhengzhou Road, Qingdao, 266042, Shandong Province, China
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Castro TMSD, Cammarota MC, Pacheco EBAV. Anaerobic co-digestion of oil refinery waste activated sludge and food waste. ENVIRONMENTAL TECHNOLOGY 2022; 43:4279-4290. [PMID: 34165033 DOI: 10.1080/09593330.2021.1946598] [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: 02/11/2021] [Accepted: 06/14/2021] [Indexed: 06/13/2023]
Abstract
The technology of anaerobic co-digestion to treat the excess biological sludge discharged from activated sludge systems in oil refineries was evaluated in bench scale experiments. Mixing food waste rich in fruits and vegetables with this sludge increased the reduction of volatile solids and biogas yield. An experimental design indicated that the best co-digestion condition was the use of waste activated sludge without previous dewatering (3.5% total solids) and food waste in an 80:20 ratio (% v/v), without the addition of inoculum. After 45 days at 35 °C, this condition resulted in volatile solid (VS) removal of 52% and biogas yield of 80.7 mL biogas/g VSadded, against only 19% and 38.5 mL biogas/g VSadded in mono-digestion of sludge alone. Anaerobic co-digestion demonstrates promising results and the potential for a simple and effective treatment method for excess biological sludge generated at refineries.
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Affiliation(s)
| | - Magali Christe Cammarota
- Environmental Engineering Program, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
- School of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Elen Beatriz Acordi Vasques Pacheco
- Environmental Engineering Program, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
- Institute of Macromolecules Professor Eloisa Mano, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
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Bareha Y, Faucher JP, Michel M, Houdon M, Vaneeckhaute C. Evaluating the impact of substrate addition for anaerobic co-digestion on biogas production and digestate quality: The case of deinking sludge. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 319:115657. [PMID: 35842989 DOI: 10.1016/j.jenvman.2022.115657] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 06/20/2022] [Accepted: 06/28/2022] [Indexed: 06/15/2023]
Abstract
To reduce greenhouse gas emissions from organic waste, anaerobic digestion has created new opportunities for energy and nutrient recovery from these wastes. However, the use of certain organic wastes in anaerobic digestion is limited due to their atypical physicochemical characteristics (e.g. unbalanced carbon to nitrogen ratio, high ash concentration). Deinking sludge is a residue from the paper recycling industry and is one of such substrates. This study aims at evaluating the impact of deinking sludge (DS) addition into a conventional co-digestion mixture on methane production and digestate quality. To this end, an integrated method was proposed, combining the analysis of physicochemical and biodegradability characteristics with parsimonious modeling using the SYS-Metha tool. The measured characteristics of the deinking sludge showed that its potential use in mono-digestion conditions is very limited. When co-digested with food waste and municipal sludge, no significant synergies or antagonisms were found. Based on these experiments, model simulations were executed to determine the optimal conditions for co-digestion with food waste and municipal sludge. A maximum of 22% of deinking sludge on a fresh mass basis can be added into a co-digestion mixture to achieve proper wet anaerobic digestion conditions. Regarding digestate quality, the addition of DS reduced nutrient and contaminants concentrations, which have an impact on digestate management, particularly for land application. Overall, the proposed methodology in this study allows determining optimal co-digestion mixtures and highlighted the limits needing further investigation under pilot/real conditions.
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Affiliation(s)
- Y Bareha
- BioEngine - Research Team on Green Process Engineering and Biorefineries, Chemical Engineering Department, Université Laval, 1065 Ave. de la Médecine, Québec, QC, G1V 0A6, Canada; CentrEau, Centre de recherche sur l'eau, Université Laval, 1065 Avenue de la Médecine, Québec, QC, G1V 0A6, Canada
| | - J-P Faucher
- Cascades CS+ Inc, 471 Boul. Marie-Victorin, Kingsey Falls, QC, J0A1B0, Canada
| | - M Michel
- Biogaz Eg Inc, 3300 Rte Marie-Victorin, Varennes, QC, J3X1P7, Canada
| | - M Houdon
- Cascades CS+ Inc, 471 Boul. Marie-Victorin, Kingsey Falls, QC, J0A1B0, Canada
| | - C Vaneeckhaute
- BioEngine - Research Team on Green Process Engineering and Biorefineries, Chemical Engineering Department, Université Laval, 1065 Ave. de la Médecine, Québec, QC, G1V 0A6, Canada; CentrEau, Centre de recherche sur l'eau, Université Laval, 1065 Avenue de la Médecine, Québec, QC, G1V 0A6, Canada.
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Huang Z, Niu Q, Nie W, Li X, Yang C. Effects of heavy metals and antibiotics on performances and mechanisms of anaerobic digestion. BIORESOURCE TECHNOLOGY 2022; 361:127683. [PMID: 35882314 DOI: 10.1016/j.biortech.2022.127683] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/18/2022] [Accepted: 07/19/2022] [Indexed: 06/15/2023]
Abstract
Anaerobic digestion (AD) is an efficacious technology to recover energy from organic wastes/wastewater, while the efficiency of AD could be limited by metals and antibiotics in substrates. It is of great significance to deeply understand the interaction mechanisms of metals and antibiotics with anaerobic microorganisms, as well as the combined effects of metals and antibiotics, which will help us break the inherent dysfunction of AD system and promote the efficient operation of AD. Therefore, this paper reviews the effects of metals, antibiotics and their combinations on AD performance, as well as the combined effects and interactional mechanisms of metals and antibiotics with anaerobic microorganisms. In addition, control strategies and future research needs are proposed. This review provides valuable information for the enhancement strategies and engineering applications of AD for organic wastes/wastewater containing metals and antibiotics.
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Affiliation(s)
- Zhiwei Huang
- College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Qiuya Niu
- College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Wenkai Nie
- College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Xiang Li
- College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Chunping Yang
- College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China; Guangdong Provincial Key Laboratory of Petrochemical Pollution Processes and Control, Key Laboratory of Petrochemical Pollution Control of Guangdong Higher Education Institutes, School of Environmental Science and Engineering, Guangdong University of Petrochemical Technology, Maoming, Guangdong 525000, China; Hunan Provincial Environmental Protection Engineering Center for Organic Pollution Control of Urban Water and Wastewater, Changsha, Hunan 410001, China.
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Temporal Variation of Nitrogen and Sulfur Species of Food Waste and Sludge during Anaerobic Co-Digestion. SUSTAINABILITY 2022. [DOI: 10.3390/su14094982] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Anaerobic co-digestion (AcoD) has been a widely accepted method to treat food waste (FW) and sewage sludge (SS). However, there is a knowledge gap regarding the key speciation transformation of nitrogen and sulfur in AcoD. Here, we explored the changes of nitrogen (N) and sulfur (S) compounds in liquid digestion and biogas, as well as the composition of microbial community structure and related metabolic functions. The results showed that H2S in the biogas was the main form of S in the early stage, and then, it was converted into SO42− and SO32−, while NH3 and NH4+ were the main forms of N during the AcoD. In addition, bacterial diversity was associated with N and S compounds; Syntrophomonas and Aminobacterium were positively correlated to H2S, NH3, NH4+ and SO32−, and Saccharibacteria_genera_incertae_sedis, Candidatus_Cloacamonas and Thermomonas were positively correlated to SO42− and NO2−. Additionally, the FAPROTAX prediction showed that the functional composition related to N and S metabolism was different from SS and inoculum after the AcoD. This study provides detailed information of conversion of N and S of the AcoD, which could lay a foundation for the subsequent regulation of the mechanism of nitrogen and sulfur compounds in the methanogenic process.
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Arelli V, Mamindlapelli NK, Begum S, Juntupally S, Anupoju GR. Solid state anaerobic digestion of food waste and sewage sludge: Impact of mixing ratios and temperature on microbial diversity, reactor stability and methane yield. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 793:148586. [PMID: 34328990 DOI: 10.1016/j.scitotenv.2021.148586] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 06/13/2021] [Accepted: 06/17/2021] [Indexed: 06/13/2023]
Abstract
Food waste (FW) and sewage sludge (SS) were anaerobically co digested under solid state conditions (Total solids >15%) and observed that mixing ratio of 3:1 and 2:1 is optimum for mesophilic and thermophilic conditions respectively. The VS reduction and methane yield at optimized ratio was 76% and 0.35 L CH4/(g VS reduced) respectively at mesophilic temperature whereas it was 88% and 0.42 L CH4/(g VS reduced) at thermophilic temperature. The metagenomic analysis for these cases were done and high throughput DNA sequencing revealed that diversified bacterial groups that participate in the different metabolisms (hydrolysis, acidogenesis and acetogenesis) were mainly dominated by the phylum Firmicutes and Bacteriodetes. Genus Methanothrix is found to be dominant which is capable of generating methane by any methanogenic pathway among all the archaeal communities in the reactors followed by Methanolinea and Methanoculleus. However, it was understood through metagenomic studies that acetotrophic pathway is observed to be the major metabolic pathway in the reactors.
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Affiliation(s)
- Vijayalakshmi Arelli
- Bioengineering and Environmental Sciences (BEES) Group, Department of Energy and Environmental Engineering (DEEE), CSIR-Indian Institute of Chemical Technology (IICT), Tarnaka, Hyderabad 500007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
| | - Naveen Kumar Mamindlapelli
- Bioengineering and Environmental Sciences (BEES) Group, Department of Energy and Environmental Engineering (DEEE), CSIR-Indian Institute of Chemical Technology (IICT), Tarnaka, Hyderabad 500007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
| | - Sameena Begum
- Bioengineering and Environmental Sciences (BEES) Group, Department of Energy and Environmental Engineering (DEEE), CSIR-Indian Institute of Chemical Technology (IICT), Tarnaka, Hyderabad 500007, India
| | - Sudharshan Juntupally
- Bioengineering and Environmental Sciences (BEES) Group, Department of Energy and Environmental Engineering (DEEE), CSIR-Indian Institute of Chemical Technology (IICT), Tarnaka, Hyderabad 500007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
| | - Gangagni Rao Anupoju
- Bioengineering and Environmental Sciences (BEES) Group, Department of Energy and Environmental Engineering (DEEE), CSIR-Indian Institute of Chemical Technology (IICT), Tarnaka, Hyderabad 500007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India.
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Monitoring of Food Waste Anaerobic Digestion Performance: Conventional Co-Substrates vs. Unmarketable Biochar Additions. Foods 2021; 10:foods10102353. [PMID: 34681402 PMCID: PMC8535009 DOI: 10.3390/foods10102353] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/17/2021] [Accepted: 08/23/2021] [Indexed: 11/16/2022] Open
Abstract
This study proposed the selection of cost-effective additives generated from different activity sectors to enhance and stabilize the start-up, as well as the transitional phases, of semi-continuous food waste (FW) anaerobic digestion. The results showed that combining agricultural waste mixtures including wheat straw (WS) and cattle manure (CM) boosted the process performance and generated up to 95% higher methane yield compared to the control reactors (mono-digested FW) under an organic loading rate (OLR) range of 2 to 3 kg VS/m3·d. Whereas R3 amended with unmarketable biochar (UBc), to around 10% of the initial fresh mass inserted, showed a significant process enhancement during the transitional phase, and more particularly at an OLR of 4 kg VS/m3·d, it was revealed that under these experimental conditions, FW reactors including UBc showed an increase of 144% in terms of specific biogas yield (SBY) compared to FW reactors fed with agricultural residue. Hence, both agricultural and industrial waste were efficacious when it came to boosting either FW anaerobic performance or AD effluent quality. Although each co-substrate performed under specific experimental conditions, this feature provides decision makers with diverse alternatives to implement a sustainable organic waste management system, conveying sufficient technical details to draw up appropriate designs for the recovery of various types of organic residue.
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Aminzadeh M, Bardi MJ, Aminirad H. A new approach to enhance the conventional two-phase anaerobic co-digestion of food waste and sewage sludge. JOURNAL OF ENVIRONMENTAL HEALTH SCIENCE & ENGINEERING 2021; 19:295-306. [PMID: 34150236 PMCID: PMC8172668 DOI: 10.1007/s40201-020-00603-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 12/15/2020] [Indexed: 06/12/2023]
Abstract
BACKGROUND Two-phase anaerobic co-digestion (TAcoD) is a versatile technology for the simultaneous treatment of organic materials and biogas production. However, the produced digestate and supernatant of the system contain heavy metals and organic substances that need to be treated prior to discharge or land application. Therefore, in this study, an innovative TAcoD for organic fertilizer and high supernatant quality achievement was proposed. METHODS In the conventional TAcoD, mixed sewage sludge (SS) and food waste (FW) were first hydrolyzed in the acidogenic reactor, and then the hydrolyzate substrate was subjected to the methanogenic reactor (TAcoD 1). In the modified TAcoD (TAcoD 2), only FW was fed into the acidogenic reactor, and the produced hydrolyzed solid was directly converted to the organic fertilizer, while the supernatant with high soluble chemical demand (SCOD) concentration was further co-digested with SS in the methanogenic reactor. RESULTS Although TAcoD 1 produced bio-methane yield and potential energy of 56.18% and 1.6-fold higher than TAcoD 2, the economical valorization of TAcoD 2 was 9-fold of that from TAcoD 1. The supernatant quality of TAcoD 2 was far better than TAcoD 1, since the SCOD, total nitrogen (TN), and total phosphor (TP) removal in TAcoD 2 and TAcoD 1 were 94.3%, 79.4%, 90.7%, and 68.9%, 28%, 46%, respectively. In terms of solid waste management, the modified TAcoD converted FW to organic fertilizer and achieved a solid reduction of 43.62% higher than that of conventional TAcoD. CONCLUSIONS This new modification in two-phase anaerobic co-digestion of food waste and sewage sludge provides a potentially feasible practice for simultaneous bio-methane, organic fertilizer, and high supernatant quality achievement. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s40201-020-00603-8.
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Affiliation(s)
- Mohammad Aminzadeh
- Faculty of Civil Engineering, Division of Environmental Engineering, Babol Noshirvani University of Technology, Babol, Iran
| | - Mohammad Javad Bardi
- Faculty of Civil Engineering, Division of Environmental Engineering, Babol Noshirvani University of Technology, Babol, Iran
| | - Hassan Aminirad
- Faculty of Civil Engineering, Division of Environmental Engineering, Babol Noshirvani University of Technology, Babol, Iran
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Gao S, Lei X, Ruan W, Zhao M. Synergetic enhancement of methane production and system resilience during anaerobic digestion of food waste in ammonia-tolerant anaerobic sludge system. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:21851-21861. [PMID: 33410077 DOI: 10.1007/s11356-020-11861-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 11/27/2020] [Indexed: 06/12/2023]
Abstract
The anaerobic digestion (AD) of food waste (FW) was augmented with ammonia-tolerant anaerobic sludge (ATAS). Different inoculum substrate ratios (ISR) under an initial ammonia stress of 4220 mg N/L were investigated. Results showed that the average specific methane production (SMP) of FW in the ATAS system increased by 36% compared with that in un-acclimated anaerobic sludge. SMP with ISR of 1:2.5 increased by approximately 6 times. Volatile fatty acids (VFAs) accumulation and sharp pH decline were not detected. These results revealed the high performance of ATAS in simultaneously relieving ammonia and acid stress. This improvement was attributed to multiple factors. ATAS had high ammonia tolerance and ability in conversion of acetate into methane. The equilibrium of NH3/NH4+, CO2/H2CO3/HCO3-, and CxHyCOOH/CxHyCOO- could promote VFAs and ammonia ionization, reduce the levels of free VFAs and ammonia, neutralize pH, and thus enhance the system's buffering capacity to be less susceptible to fluctuations. These results demonstrated that employing ATAS in improving AD performance and resilience from acid and ammonia inhibition is feasible and effective.
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Affiliation(s)
- Shumei Gao
- College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing, 314001, Zhejiang Province, China
- School of Environment and Civil Engineering, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, Jiangsu Province, China
- Jiangsu Key Laboratory of Anaerobic Biotechnology (Jiangnan University), Wuxi, 214122, Jiangsu Province, China
| | - Xinyu Lei
- College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing, 314001, Zhejiang Province, China
| | - Wenquan Ruan
- School of Environment and Civil Engineering, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, Jiangsu Province, China
- Jiangsu Key Laboratory of Anaerobic Biotechnology (Jiangnan University), Wuxi, 214122, Jiangsu Province, China
| | - Mingxing Zhao
- School of Environment and Civil Engineering, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, Jiangsu Province, China.
- Jiangsu Key Laboratory of Anaerobic Biotechnology (Jiangnan University), Wuxi, 214122, Jiangsu Province, China.
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Multiple Effects of Different Nickel Concentrations on the Stability of Anaerobic Digestion of Molasses. SUSTAINABILITY 2021. [DOI: 10.3390/su13094971] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Molasses is a highly thick by-product produced after sugarcane crystallization constitutes large amounts of biodegradable organics. These organic compounds can be converted to renewable products through anaerobic digestion. Nevertheless, its anaerobic digestion is limited due to its high chemical oxygen demand (COD) and ion concentration. The effects of nickel (Ni2+) on the stability of anaerobic digestion of molasses were established by studying the degradation of organic matter (COD removal rate), biogas yield, methane content in the biogas, pH, and alkalinity. The results showed that there were no significant effects on the stability of pH and alkalinity. Increased COD removal rate and higher methane content was observed by 2–3% in the digesters receiving 2 and 4 mg/L of Ni2+ in the first phase of the experiment. Ni2+ supplemented to reactors at concentration 2 mg/L enhanced biogas yield. Overall, it is suggested that the addition of Ni2+ has some effects on the enhancement of biogas yield and methane contents but has no obvious effects on the long-lasting stability of the molasses digestion.
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Bardi MJ, Oliaee MA. Impacts of different operational temperatures and organic loads in anaerobic co-digestion of food waste and sewage sludge on the fate of SARS-CoV-2. PROCESS SAFETY AND ENVIRONMENTAL PROTECTION : TRANSACTIONS OF THE INSTITUTION OF CHEMICAL ENGINEERS, PART B 2021; 146:464-472. [PMID: 33262558 PMCID: PMC7694560 DOI: 10.1016/j.psep.2020.11.035] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/16/2020] [Accepted: 11/21/2020] [Indexed: 05/05/2023]
Abstract
The impacts of different operational temperatures, and organic load (OL) on the fate of SARS-CoV-2 during the anaerobic co-digestion of food waste (FW) and sewage sludge (SS) was evaluated. The lab-scaled batch reactors (i.e. R1-R7) were performed under psychrophilic, mesophilic, and thermophilic conditions and the OL of systems was 1.5, 3.5, 6 gVS/L. The performance parameters showed that at higher OL the stability of systems failed and low biogas was produced. In contrast, increasing of operational temperature of systems induced more biogas generation due to the increment of metabolic activity of bacteria. Therefore, R1-R7 achieved biogas yield of 202.5, 249, 187, 260, 246, 163, and 300 mL/gVS respectively. Both SARS-CoV-2 genes i.e. ORF1ab, and N genes were detected in the effluent of psychrophilic reactors i.e. R1, and R2, with a total concentration of 46 × 103, and 11 × 103 copies/L respectively. In R3, no viral genes were observed, when the VFAs was accumulated up to 2000 mg/L and caused a pH drop to 5.6. At the mesophilic condition, the viral concentration was significantly declined, and no viral genes were observed at an OL of 3.5 gVS/L. Furthermore, the synergistic effect of temperature and accumulation of intermediate metabolites provided a sever condition for SARS-CoV-2 survival at an operational temperature and OL of 50 °C, and 1.5 gVS/L respectively.
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Affiliation(s)
- Mohammad Javad Bardi
- Faculty of Civil Engineering, Division of Environmental Engineering, Babol Noshirvani University of Technology, Babol, Iran
| | - Mohammad Amin Oliaee
- Faculty of Civil Engineering, Division of Environmental Engineering, Babol Noshirvani University of Technology, Babol, Iran
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