1
|
Tang Y, Chu S, Su P, Guo R, Duan Y, Wang Y. Freezing method assists calcium hypochlorite for synergistically promoting methane production from sludge anaerobic digestion. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 324:116243. [PMID: 36155084 DOI: 10.1016/j.jenvman.2022.116243] [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: 07/23/2022] [Revised: 09/04/2022] [Accepted: 09/08/2022] [Indexed: 06/16/2023]
Abstract
Anaerobic digestion is widely considered to be a promising technology for waste activated sludge (WAS) treatment, by which sludge stabilization and resource recovery are simultaneously achieved. The poor reaction efficiency however hinders the large-scale applications of WAS anaerobic digestion technology. This study reported an efficient sludge pretreatment method by combining freezing with calcium hypochlorite (Ca(ClO)2) for enhancing the anaerobic digestion efficiency. Experimental data showed that the optimal combination was freezing at -20 °C coupled with 0.075 g/g VSS (volatile suspended solids) Ca(ClO)2, by which the maximum biomethane production of 274.4 ± 8.2 mL/g VSS was realized, 1.62 times higher than that of the control. Model-based analysis demonstrated that higher potential and rate for methane production were attained by the combined pretreatment. Mechanism analysis revealed that the extracellular polymeric substances (EPS) and microbial cells were both effectively destructed when treated by combined freezing and Ca(ClO)2, and more dissolved organics were generated in consequence. Microbial analysis demonstrated that the co-treated reactor enriched more functional microbes (such as Methanosaeta, Methanosarcina and Candidatus_Methanofastidiosum) responsible for biomethane generation than that of the control. Furthermore, the number of fecal coliform was largely reduced in co-treated reactor. As the correlation between sludge anaerobic digestion performance and numerous pretreatment parameters was systematically revealed, this study can provide important references for engineers when applying the combined freezing and Ca(ClO)2 technology in practical engineering.
Collapse
Affiliation(s)
- Yujia Tang
- School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Guangdong University of Technology, Guangzhou, 510006, China
| | - Shuangshuang Chu
- School of Environmental Science and Engineering, Guangdong Provincial Key Lab of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, 510275, China
| | - Peixin Su
- School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Guangdong University of Technology, Guangzhou, 510006, China
| | - Ruichao Guo
- School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Guangdong University of Technology, Guangzhou, 510006, China
| | - Yan Duan
- School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Guangdong University of Technology, Guangzhou, 510006, China
| | - Yujie Wang
- School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Guangdong University of Technology, Guangzhou, 510006, China.
| |
Collapse
|
2
|
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.
Collapse
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.
| |
Collapse
|
3
|
Gievers F, Walz M, Loewe K, Bienert C, Loewen A. Anaerobic co-digestion of paper sludge: Feasibility of additional methane generation in mechanical-biological treatment plants. WASTE MANAGEMENT (NEW YORK, N.Y.) 2022; 144:502-512. [PMID: 35462294 DOI: 10.1016/j.wasman.2022.04.016] [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: 01/19/2022] [Revised: 03/31/2022] [Accepted: 04/11/2022] [Indexed: 06/14/2023]
Abstract
In this work, the feasibility of the anaerobic digestion of paper sludge as a co-substrate in anaerobic digestion mechanical-biological treatment (MBT) plants is investigated. In the first phase, the biochemical properties, biomethane potential (BMP), and pollutant contents of 20 different industrial paper sludges are determined. Following the general evaluation in the BMP tests, the second phase of the project involves the semi-continuous co-digestion of six paper sludges in continuous stirred reactors (CSTR). Paper sludges are categorized according to their origin within the pulp and paper mills: Deinking Sludge (DS), Primary Sludge (PS) and Biological Sludge (BS). The analysis of potentially inhibiting elements shows that the concentrations of chlororganic compounds, mineral oil and some heavy metals are highest in DS, while the mean heavy metal loads in all paper sludges are relatively low compared to other industrial sludges. Large differences in total solids (TS) and volatile solids (VS) contents are observed among the different paper sludges investigated, with DS having the highest TS due to the high inorganic contents. The BMP of the investigated sludges ranges from 90 to 355 NL CH4 kg-1 VS. In subsequent semi-continuous co-digestion experiments simulating MBT conditions, three DS and two fiber sludges (a mixture of PS and BS) show good methane generation rates, while one fiber sludge causes inhibition and indicates an increase in viscosity. In general, co-digestion of paper sludge in anaerobic digestion MBT plants can be a viable option for energy production and also facilitates a safe disposal of the paper sludge digestates.
Collapse
Affiliation(s)
- Fabian Gievers
- Faculty of Resource Management, University of Applied Sciences and Arts (HAWK), Rudolf-Diesel-Straße 12, 37075 Göttingen, Germany; Faculty of Waste and Resource Management, University of Rostock, Justus-v.-Liebig-Weg 6, 18059 Rostock, Germany.
| | - Meike Walz
- Faculty of Resource Management, University of Applied Sciences and Arts (HAWK), Rudolf-Diesel-Straße 12, 37075 Göttingen, Germany
| | - Kirsten Loewe
- Faculty of Resource Management, University of Applied Sciences and Arts (HAWK), Rudolf-Diesel-Straße 12, 37075 Göttingen, Germany
| | | | - Achim Loewen
- Faculty of Resource Management, University of Applied Sciences and Arts (HAWK), Rudolf-Diesel-Straße 12, 37075 Göttingen, Germany
| |
Collapse
|
4
|
Kinetic study and performance evaluation of an integrated two-phase fixed-film baffled bioreactor for bioenergy recovery from wastewater and bio-wasted sludge. RENEWABLE & SUSTAINABLE ENERGY REVIEWS 2020. [DOI: 10.1016/j.rser.2019.109674] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
|