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Rodriguez-Chiang L, Vanhatalo K, Llorca J, Dahl O. New alternative energy pathway for chemical pulp mills: From traditional fibers to methane production. BIORESOURCE TECHNOLOGY 2017; 235:265-273. [PMID: 28371764 DOI: 10.1016/j.biortech.2017.03.140] [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: 02/04/2017] [Revised: 03/17/2017] [Accepted: 03/22/2017] [Indexed: 06/07/2023]
Abstract
Chemical pulp mills have a need to diversify their end-product portfolio due to the current changing bio-economy. In this study, the methane potential of brown, oxygen delignified and bleached pulp were evaluated in order to assess the potential of converting traditional fibers; as well as microcrystalline cellulose and filtrates; to energy. Results showed that high yields (380mL CH4/gVS) were achieved with bleached fibers which correlates with the lower presence of lignin. Filtrates from the hydrolysis process on the other hand, had the lowest yields (253mL CH4/gVS) due to the high amount of acid and lignin compounds that cause inhibition. Overall, substrates had a biodegradability above 50% which demonstrates that they can be subjected to efficient anaerobic digestion. An energy and cost estimation showed that the energy produced can be translated into a significant profit and that methane production can be a promising new alternative option for chemical pulp mills.
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Affiliation(s)
- Lourdes Rodriguez-Chiang
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University. P.O. Box 16300, Vuorimiehentie 1, Espoo, Finland; Institute of Energy Technologies and Barcelona Research Center in Multiscale Science and Engineering, Technical University of Catalonia, Barcelona, Spain.
| | - Kari Vanhatalo
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University. P.O. Box 16300, Vuorimiehentie 1, Espoo, Finland
| | - Jordi Llorca
- Institute of Energy Technologies and Barcelona Research Center in Multiscale Science and Engineering, Technical University of Catalonia, Barcelona, Spain
| | - Olli Dahl
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University. P.O. Box 16300, Vuorimiehentie 1, Espoo, Finland
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52
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Caicedo LM, Wang H, Lu W, De Clercq D, Liu Y, Xu S, Ni Z. Effect of initial bulk density on high-solids anaerobic digestion of MSW: General mechanism. BIORESOURCE TECHNOLOGY 2017; 233:332-341. [PMID: 28285226 DOI: 10.1016/j.biortech.2017.02.107] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 02/17/2017] [Accepted: 02/22/2017] [Indexed: 06/06/2023]
Abstract
Initial bulk density (IBD) is an important variable in anaerobic digestion since it defines and optimizes the treatment capacity of a system. This study reveals the mechanism on how IBD might affect anaerobic digestion of waste. Four different IBD values: D1 (500-700kgm-3), D2 (900-1000kgm-3), D3 (1100-1200kgm-3) and D4 (1200-1400kgm-3) were set and tested over a period of 90days in simulated landfill reactors. The main variables affected by the IBD are the methane generation, saturation degree, extraction of organic matter, and the total population of methanogens. The study identified that IBD >1000kgm-3 may have significant effect on methane generation, either prolonging the lag time or completely inhibiting the process. This study provides a new understanding of the anaerobic digestion process in saturated high-solids systems.
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Affiliation(s)
- Luis M Caicedo
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Hongtao Wang
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Wenjing Lu
- School of Environment, Tsinghua University, Beijing 100084, China.
| | - Djavan De Clercq
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Yanjun Liu
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Sai Xu
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Zhe Ni
- School of Environment, Tsinghua University, Beijing 100084, China
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53
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Assessment of regional biomass as co-substrate in the anaerobic digestion of chicken manure: Impact of co-digestion with chicken processing waste, seagrass and Miscanthus. Biochem Eng J 2017. [DOI: 10.1016/j.bej.2016.11.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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54
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Mahdy A, Fotidis IA, Mancini E, Ballesteros M, González-Fernández C, Angelidaki I. Ammonia tolerant inocula provide a good base for anaerobic digestion of microalgae in third generation biogas process. BIORESOURCE TECHNOLOGY 2017; 225:272-278. [PMID: 27898317 DOI: 10.1016/j.biortech.2016.11.086] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 11/20/2016] [Accepted: 11/21/2016] [Indexed: 06/06/2023]
Abstract
This study investigated the ability of an ammonia-acclimatized inoculum to digest efficiently protein-rich microalgae for continuous 3rd generation biogas production. Moreover, we investigated whether increased C/N ratio could alleviate ammonia toxicity. The biochemical methane potential (BMP) of five different algae (Chlorella vulgaris)/manure (cattle) mixtures showed that the mixture of 80/20 (on VS basis) resulted in the highest BMP value (431mLCH4 gVS-1), while the BMP of microalgae alone (100/0) was 415mLCH4 gVS-1. Subsequently, anaerobic digestion of those two substrates was tested in continuous stirred tank reactors (CSTR). Despite of the high ammonium levels (3.7-4.2g NH4+-NL-1), CSTR reactors using ammonia tolerant inoculum resulted in relatively high methane yields (i.e. 77.5% and 84% of the maximum expected, respectively). These results demonstrated that ammonia tolerant inocula could be a promising approach to successfully digest protein-rich microalgae and achieve a 3rd generation biogas production.
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Affiliation(s)
- Ahmed Mahdy
- Biotechnological Processes for Energy Production Unit - IMDEA Energy, 28935 Móstoles, Madrid, Spain; Department of Agricultural Microbiology, Faculty of Agriculture, Zagazig University, 44511 Zagazig, Egypt
| | - Ioannis A Fotidis
- Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet Bygning 115, DK-2800 Kgs. Lyngby, Denmark.
| | - Enrico Mancini
- Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet Bygning 115, DK-2800 Kgs. Lyngby, Denmark
| | - Mercedes Ballesteros
- Biotechnological Processes for Energy Production Unit - IMDEA Energy, 28935 Móstoles, Madrid, Spain; Biofuels Unit - Research Center for Energy, Environment and Technology (CIEMAT), 28040 Madrid, Spain
| | | | - Irini Angelidaki
- Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet Bygning 115, DK-2800 Kgs. Lyngby, Denmark
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55
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Wang B, Björn A, Strömberg S, Nges IA, Nistor M, Liu J. Evaluating the influences of mixing strategies on the Biochemical Methane Potential test. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2017; 185:54-59. [PMID: 28314396 DOI: 10.1016/j.jenvman.2016.10.044] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 10/19/2016] [Accepted: 10/21/2016] [Indexed: 06/06/2023]
Abstract
Mixing plays an important role in the Biochemical Methane Potential (BMP) test, but only limited efforts have been put into it. In this study, various mixing strategies were applied to evaluate the influences on the BMP test, i.e., no mixing, shaking in water bath, shake manually once per day (SKM), automated unidirectional and bidirectional mixing. The results show that the effects of mixing are prominent for the most viscous substrate investigated, as both the highest methane production and highest maximal daily methane production were obtained at the highest mixing intensity. However, the organic removal efficiencies were not affected, which might offer evidence that mixing helps the release of gases trapped in digester liquid. Moreover, mixing is required for improved methane production when the digester content is viscous, conversely, mixing is unnecessary or SKM might be sufficient for the BMP test if the digester content is quite dilute or the substrate is easily degraded.
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Affiliation(s)
- Bing Wang
- Division of Biotechnology, Lund University, Naturvetarvägen 16, SE-222 41, Lund, Sweden.
| | - Annika Björn
- Department of Thematic Studies-Environmental Change, Linköping University, SE-581 83, Linköping, Sweden
| | - Sten Strömberg
- Bioprocess Control Sweden AB, Scheelevägen 22, SE-223 63, Lund, Sweden
| | - Ivo Achu Nges
- Division of Biotechnology, Lund University, Naturvetarvägen 16, SE-222 41, Lund, Sweden
| | - Mihaela Nistor
- Bioprocess Control Sweden AB, Scheelevägen 22, SE-223 63, Lund, Sweden
| | - Jing Liu
- Division of Biotechnology, Lund University, Naturvetarvägen 16, SE-222 41, Lund, Sweden; Bioprocess Control Sweden AB, Scheelevägen 22, SE-223 63, Lund, Sweden
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56
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Holliger C, Alves M, Andrade D, Angelidaki I, Astals S, Baier U, Bougrier C, Buffière P, Carballa M, de Wilde V, Ebertseder F, Fernández B, Ficara E, Fotidis I, Frigon JC, de Laclos HF, Ghasimi DSM, Hack G, Hartel M, Heerenklage J, Horvath IS, Jenicek P, Koch K, Krautwald J, Lizasoain J, Liu J, Mosberger L, Nistor M, Oechsner H, Oliveira JV, Paterson M, Pauss A, Pommier S, Porqueddu I, Raposo F, Ribeiro T, Rüsch Pfund F, Strömberg S, Torrijos M, van Eekert M, van Lier J, Wedwitschka H, Wierinck I. Towards a standardization of biomethane potential tests. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2016; 74:2515-2522. [PMID: 27973356 DOI: 10.2166/wst.2016.336] [Citation(s) in RCA: 271] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Production of biogas from different organic materials is a most interesting source of renewable energy. The biomethane potential (BMP) of these materials has to be determined to get insight in design parameters for anaerobic digesters. Although several norms and guidelines for BMP tests exist, inter-laboratory tests regularly show high variability of BMPs for the same substrate. A workshop was held in June 2015, in Leysin, Switzerland, with over 40 attendees from 30 laboratories around the world, to agree on common solutions to the conundrum of inconsistent BMP test results. This paper presents the consensus of the intense roundtable discussions and cross-comparison of methodologies used in respective laboratories. Compulsory elements for the validation of BMP results were defined. They include the minimal number of replicates, the request to carry out blank and positive control assays, a criterion for the test duration, details on BMP calculation, and last but not least criteria for rejection of the BMP tests. Finally, recommendations on items that strongly influence the outcome of BMP tests such as inoculum characteristics, substrate preparation, test setup, and data analysis are presented to increase the probability of obtaining validated and reproducible results.
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Affiliation(s)
- Christof Holliger
- ENAC IIE Laboratory for Environmental Biotechnology, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland E-mail:
| | - Madalena Alves
- Centre of Biological Engineering, University of Minho, Braga, Portugal
| | - Diana Andrade
- Bavarian State Research Center for Agriculture, Freising, Germany
| | | | - Sergi Astals
- Advanced Water Management Center, The University of Queensland, Brisbane, Australia
| | - Urs Baier
- Institute for Chemistry and Biotechnology, ZHAW School of Life Sciences and Facility Management, Wädenswil, Switzerland
| | | | | | - Marta Carballa
- Department of Chemical Engineering, Institute of Technology, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Vinnie de Wilde
- Sub-Department of Environmental Technology, Wageningen University, Wageningen, The Netherlands
| | | | | | | | | | | | | | | | - Gabrielle Hack
- ENAC IIE Laboratory for Environmental Biotechnology, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland E-mail:
| | - Mathias Hartel
- Bavarian State Research Center for Agriculture, Freising, Germany
| | | | | | - Pavel Jenicek
- University of Chemistry and Technology Prague, Prague, Czech Republic
| | - Konrad Koch
- Chair of Urban Water Systems Engineering, Technical University of Munich, Garching, Germany
| | - Judith Krautwald
- Institute for Chemistry and Biotechnology, ZHAW School of Life Sciences and Facility Management, Wädenswil, Switzerland
| | - Javier Lizasoain
- University of Natural Resources and Life Sciences, Vienna, Austria
| | - Jing Liu
- Bioprocess Control AB, Lund, Sweden
| | - Lona Mosberger
- Institute for Chemistry and Biotechnology, ZHAW School of Life Sciences and Facility Management, Wädenswil, Switzerland
| | | | - Hans Oechsner
- State Institute of Agricultural Engineering and Bioenergy, University of Hohenheim, Stuttgart, Germany
| | | | - Mark Paterson
- Association for Technology and Structures in Agriculture (KTBL), Darmstadt, Germany
| | - André Pauss
- Sorbonne Universités, EA 4297 TIMR UTC/ESCOM, Compiègne, France
| | | | | | - Francisco Raposo
- Instituto de la Grasa, Consejo Superior de Investigaciones Científicas, Seville, Spain
| | - Thierry Ribeiro
- Département des Sciences et Techniques Agro-Industrielles, Institut Polytechnique LaSalle Beauvais, Beauvais, France
| | - Florian Rüsch Pfund
- Institute for Chemistry and Biotechnology, ZHAW School of Life Sciences and Facility Management, Wädenswil, Switzerland
| | | | - Michel Torrijos
- INRA, UR0050, Laboratoire de Biotechnologie de l'Environnement, Narbonne, France
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57
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Rodriguez-Chiang L, Llorca J, Dahl O. Anaerobic co-digestion of acetate-rich with lignin-rich wastewater and the effect of hydrotalcite addition. BIORESOURCE TECHNOLOGY 2016; 218:84-91. [PMID: 27347802 DOI: 10.1016/j.biortech.2016.06.074] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 06/16/2016] [Accepted: 06/19/2016] [Indexed: 06/06/2023]
Abstract
The methane potential and biodegradability of different ratios of acetate and lignin-rich effluents from a neutral sulfite semi-chemical (NSSC) pulp mill were investigated. Results showed ultimate methane yields up to 333±5mLCH4/gCOD when only acetate-rich substrate was added and subsequently lower methane potentials of 192±4mLCH4/gCOD when the lignin fraction was increased. The presence of lignin showed a linear decay in methane production, resulting in a 41% decrease in methane when the lignin-rich feed had a 30% increase. A negative linear correlation between lignin content and biodegradability was also observed. Furthermore, the effect of hydrotalcite (HT) addition was evaluated and showed increase in methane potential of up to 8%, a faster production rate and higher soluble lignin removal (7-12% higher). Chemical oxygen demand (COD) removal efficiencies between 64 and 83% were obtained for all samples.
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Affiliation(s)
- Lourdes Rodriguez-Chiang
- Department of Forest Products Technology, School of Chemical Technology, Aalto University, P.O. Box 16300, Vuorimiehentie 1, Espoo, Finland; Institute of Energy Technologies, Technical University of Catalonia, Barcelona, Spain.
| | - Jordi Llorca
- Institute of Energy Technologies, Technical University of Catalonia, Barcelona, Spain
| | - Olli Dahl
- Department of Forest Products Technology, School of Chemical Technology, Aalto University, P.O. Box 16300, Vuorimiehentie 1, Espoo, Finland
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58
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Anaerobic Codigestion of Municipal Wastewater Treatment Plant Sludge with Food Waste: A Case Study. BIOMED RESEARCH INTERNATIONAL 2016; 2016:8462928. [PMID: 27689091 PMCID: PMC5027371 DOI: 10.1155/2016/8462928] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 06/10/2016] [Accepted: 06/30/2016] [Indexed: 11/30/2022]
Abstract
The aim of this study was to assess the effects of the codigestion of food manufacturing and processing wastes (FW) with sewage sludge (SS), that is, municipal wastewater treatment plant primary sludge and waste activated sludge. Bench scale mesophilic anaerobic reactors were fed intermittently with varying ratio of SS and FW and operated at a hydraulic retention time of 20 days and organic loading of 2.0 kg TS/m3·d. The specific biogas production (SBP) increased by 25% to 50% with the addition of 1%–5% FW to SS which is significantly higher than the SBP from SS of 284 ± 9.7 mLN/g VS added. Although the TS, VS, and tCOD removal slightly increased, the biogas yield and methane content improved significantly and no inhibitory effects were observed as indicated by the stable pH throughout the experiment. Metal screening of the digestate suggested the biosolids meet the guidelines for use as a soil conditioner. Batch biochemical methane potential tests at different ratios of SS : FW were used to determine the optimum ratio using surface model analysis. The results showed that up to 47-48% FW can be codigested with SS. Overall these results confirm that codigestion has great potential in improving the methane yield of SS.
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59
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O'Shea R, Wall D, Murphy JD. Modelling a demand driven biogas system for production of electricity at peak demand and for production of biomethane at other times. BIORESOURCE TECHNOLOGY 2016; 216:238-49. [PMID: 27240240 DOI: 10.1016/j.biortech.2016.05.050] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 05/12/2016] [Accepted: 05/14/2016] [Indexed: 06/05/2023]
Abstract
Four feedstocks were assessed for use in a demand driven biogas system. Biomethane potential (BMP) assays were conducted for grass silage, food waste, Laminaria digitata and dairy cow slurry. Semi-continuous trials were undertaken for all feedstocks, assessing biogas and biomethane production. Three kinetic models of the semi-continuous trials were compared. A first order model most accurately correlated with gas production in the pulse fed semi-continuous system. This model was developed for production of electricity on demand, and biomethane upgrading. The model examined a theoretical grass silage digester that would produce 435kWe in a continuous fed system. Adaptation to demand driven biogas required 187min to produce sufficient methane to run a 2MWe combined heat and power (CHP) unit for 60min. The upgrading system was dispatched 71min following CHP shutdown. Of the biogas produced 21% was used in the CHP and 79% was used in the upgrading system.
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Affiliation(s)
- R O'Shea
- MaREI Centre, Environmental Research Institute (ERI), University College Cork (UCC), Ireland; School of Engineering, UCC, Ireland
| | - D Wall
- MaREI Centre, Environmental Research Institute (ERI), University College Cork (UCC), Ireland; School of Engineering, UCC, Ireland.
| | - J D Murphy
- MaREI Centre, Environmental Research Institute (ERI), University College Cork (UCC), Ireland; School of Engineering, UCC, Ireland
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60
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Petersen SO, Olsen AB, Elsgaard L, Triolo JM, Sommer SG. Estimation of Methane Emissions from Slurry Pits below Pig and Cattle Confinements. PLoS One 2016; 11:e0160968. [PMID: 27529692 PMCID: PMC4986936 DOI: 10.1371/journal.pone.0160968] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 07/27/2016] [Indexed: 11/24/2022] Open
Abstract
Quantifying in-house emissions of methane (CH4) from liquid manure (slurry) is difficult due to high background emissions from enteric processes, yet of great importance for correct estimation of CH4 emissions from manure management and effects of treatment technologies such as anaerobic digestion. In this study CH4 production rates were determined in 20 pig slurry and 11 cattle slurry samples collected beneath slatted floors on six representative farms; rates were determined within 24 h at temperatures close to the temperature in slurry pits at the time of collection. Methane production rates in pig and cattle slurry differed significantly at 0.030 and 0.011 kg CH4 kg-1 VS (volatile solids). Current estimates of CH4 emissions from pig and cattle manure management correspond to 0.032 and 0.015 kg CH4 kg-1, respectively, indicating that slurry pits under animal confinements are a significant source. Fractions of degradable volatile solids (VSd, kg kg-1 VS) were estimated using an aerobic biodegradability assay and total organic C analyses. The VSd in pig and cattle slurry averaged 0.51 and 0.33 kg kg-1 VS, and it was estimated that on average 43 and 28% of VSd in fresh excreta from pigs and cattle, respectively, had been lost at the time of sampling. An empirical model of CH4 emissions from slurry was reparameterised based on experimental results. A sensitivity analysis indicated that predicted CH4 emissions were highly sensitive to uncertainties in the value of lnA of the Arrhenius equation, but much less sensitive to uncertainties in VSd or slurry temperature. A model application indicated that losses of carbon in VS as CO2 may be much greater than losses as CH4. Implications of these results for the correct estimation of CH4 emissions from manure management, and for the mitigation potential of treatments such as anaerobic digestion, are discussed.
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Affiliation(s)
- Søren O. Petersen
- Department of Agroecology, Aarhus University, Tjele, Denmark
- * E-mail:
| | - Anne B. Olsen
- Department of Agroecology, Aarhus University, Tjele, Denmark
| | - Lars Elsgaard
- Department of Agroecology, Aarhus University, Tjele, Denmark
| | - Jin Mi Triolo
- Institute of Chemical Engineering, Biotechnology and Environmental Technology, University of Southern Denmark, Odense, Denmark
| | - Sven G. Sommer
- Institute of Chemical Engineering, Biotechnology and Environmental Technology, University of Southern Denmark, Odense, Denmark
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61
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Poggio D, Walker M, Nimmo W, Ma L, Pourkashanian M. Modelling the anaerobic digestion of solid organic waste - Substrate characterisation method for ADM1 using a combined biochemical and kinetic parameter estimation approach. WASTE MANAGEMENT (NEW YORK, N.Y.) 2016; 53:40-54. [PMID: 27156366 DOI: 10.1016/j.wasman.2016.04.024] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 04/21/2016] [Accepted: 04/22/2016] [Indexed: 06/05/2023]
Abstract
This work proposes a novel and rigorous substrate characterisation methodology to be used with ADM1 to simulate the anaerobic digestion of solid organic waste. The proposed method uses data from both direct substrate analysis and the methane production from laboratory scale anaerobic digestion experiments and involves assessment of four substrate fractionation models. The models partition the organic matter into a mixture of particulate and soluble fractions with the decision on the most suitable model being made on quality of fit between experimental and simulated data and the uncertainty of the calibrated parameters. The method was tested using samples of domestic green and food waste and using experimental data from both short batch tests and longer semi-continuous trials. The results showed that in general an increased fractionation model complexity led to better fit but with increased uncertainty. When using batch test data the most suitable model for green waste included one particulate and one soluble fraction, whereas for food waste two particulate fractions were needed. With richer semi-continuous datasets, the parameter estimation resulted in less uncertainty therefore allowing the description of the substrate with a more complex model. The resulting substrate characterisations and fractionation models obtained from batch test data, for both waste samples, were used to validate the method using semi-continuous experimental data and showed good prediction of methane production, biogas composition, total and volatile solids, ammonia and alkalinity.
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Affiliation(s)
- D Poggio
- Energy Research Institute, School of Chemical and Process Engineering, University of Leeds, LS2 9JT, UK
| | - M Walker
- Energy Engineering Group, Mechanical Engineering, University of Sheffield, S10 2TN, UK.
| | - W Nimmo
- Energy Engineering Group, Mechanical Engineering, University of Sheffield, S10 2TN, UK
| | - L Ma
- Energy Engineering Group, Mechanical Engineering, University of Sheffield, S10 2TN, UK
| | - M Pourkashanian
- Energy Engineering Group, Mechanical Engineering, University of Sheffield, S10 2TN, UK
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62
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Bellaton S, Guérin S, Pautremat N, Bernier J, Muller M, Motellet S, Azimi S, Pauss A, Rocher V. Early assessment of a rapid alternative method for the estimation of the biomethane potential of sewage sludge. BIORESOURCE TECHNOLOGY 2016; 206:279-284. [PMID: 26869069 DOI: 10.1016/j.biortech.2016.01.139] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 01/18/2016] [Accepted: 01/19/2016] [Indexed: 06/05/2023]
Abstract
This short communication briefly presents a rapid method using a fluorescent redox indicator, similar to resazurin, in order to estimate the biodegradability of sewage sludge during anaerobic digestion (AD). The biodegradability and by extension the Biochemical Methane Potential (BMP) of nineteen municipal sludge samples (primary, biological and tertiary) were investigated and estimated in only 48 h. Results showed the relevance to follow the metabolic activity of anaerobic sludge by the kinetic of probe reduction. The extended lag phase of inoculum indicated an impact of pre-treatments on enzyme activity. The comparison with Automatic Methane Potential Test System II (AMPTS) confirmed the estimated values of BMP according to an uncertainty limit of 25%. These first results highlight the interest of this rapid assay as a preliminary tool of the biodegradability of sewage sludge in anaerobic digestion.
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Affiliation(s)
- Solenn Bellaton
- AMS Envolure, 1682 rue de la Valsière, 34184 Montpellier Cedex 4, France.
| | - Sabrina Guérin
- SIAAP, Direction du Développement et de la Prospective, 82 Avenue Kléber, 92700 Colombes, France
| | - Nathalie Pautremat
- AMS Envolure, 1682 rue de la Valsière, 34184 Montpellier Cedex 4, France; SCANAE, 1682 rue de la Valsière, 34790 Grabels, France
| | - Jean Bernier
- SIAAP, Direction du Développement et de la Prospective, 82 Avenue Kléber, 92700 Colombes, France
| | - Mathieu Muller
- AMS Envolure, 1682 rue de la Valsière, 34184 Montpellier Cedex 4, France
| | - Stéphane Motellet
- Centre de Recherche Royallieu, Université Technologique de Compiègne, BP 20529, rue Personne de Roberval, 60205 Compiègne Cedex, France
| | - Sam Azimi
- SIAAP, Direction du Développement et de la Prospective, 82 Avenue Kléber, 92700 Colombes, France
| | - André Pauss
- Centre de Recherche Royallieu, Université Technologique de Compiègne, BP 20529, rue Personne de Roberval, 60205 Compiègne Cedex, France
| | - Vincent Rocher
- SIAAP, Direction du Développement et de la Prospective, 82 Avenue Kléber, 92700 Colombes, France
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63
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Koch K, Huber B, Bajón Fernández Y, Drewes JE. Methane from CO₂: Influence of different CO₂ concentrations in the flush gas on the methane production in BMP tests. WASTE MANAGEMENT (NEW YORK, N.Y.) 2016; 49:36-39. [PMID: 26818184 DOI: 10.1016/j.wasman.2016.01.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 01/17/2016] [Accepted: 01/17/2016] [Indexed: 06/05/2023]
Abstract
The influence of carbon dioxide (CO2) in the headspace gas on the specific methane (CH4) production of blank samples with just inoculum during Biochemical Methane Potential (BMP) tests was studied. The headspace of the bottles had been flushed with 15 different ratios of CO2 and N2 prior to incubation, while they were treated otherwise identically. The results revealed that the CH4 yield increased linearly with higher ratio of CO2 in the flush gas reaching a 30% higher yield at pure CO2 relative to pure N2 headspace conditions. However, a slightly distinct lag is noticeable during the initial phase of the degradation process at high ratios of CO2, hypothesizing a reversible disturbance of the biocenosis. Further experiments and analyses need to be performed to elucidate the underlying mechanisms.
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Affiliation(s)
- Konrad Koch
- Chair of Urban Water Systems Engineering, Technical University of Munich, Am Coulombwall 8, D-85748 Garching, Germany.
| | - Bettina Huber
- Chair of Urban Water Systems Engineering, Technical University of Munich, Am Coulombwall 8, D-85748 Garching, Germany; Bavarian State Research Center for Agriculture, Central Department for Quality Assurance and Analytics, Lange Point 6, D-85354 Freising, Germany
| | - Yadira Bajón Fernández
- Cranfield Water Science Institute, School of Energy, Environment and Agrifood, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK
| | - Jörg E Drewes
- Chair of Urban Water Systems Engineering, Technical University of Munich, Am Coulombwall 8, D-85748 Garching, Germany
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64
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Ward AJ. Near-Infrared Spectroscopy for Determination of the Biochemical Methane Potential: State of the Art. Chem Eng Technol 2016. [DOI: 10.1002/ceat.201500315] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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65
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Valero D, Montes JA, Rico JL, Rico C. Influence of headspace pressure on methane production in Biochemical Methane Potential (BMP) tests. WASTE MANAGEMENT (NEW YORK, N.Y.) 2016; 48:193-198. [PMID: 26598214 DOI: 10.1016/j.wasman.2015.11.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 10/29/2015] [Accepted: 11/07/2015] [Indexed: 06/05/2023]
Abstract
The biochemical methane potential test is the most commonly applied method to determine methane production from organic wastes. One of the parameters measured is the volume of biogas produced which can be determined manometrically by keeping the volume constant and measuring increases in pressure. In the present study, the effect of pressure accumulation in the headspace of the reactors has been studied. Triplicate batch trials employing cocoa shell, waste coffee grounds and dairy manure as substrates have been performed under two headspace pressure conditions. The results obtained in the study showed that headspace overpressures higher than 600mbar affected methane production for waste coffee grounds. On the contrary, headspace overpressures within a range of 600-1000mbar did not affect methane production for cocoa shell and dairy manure. With the analyses performed in the present work it has not been possible to determine the reasons for the lower methane yield value obtained for the waste coffee grounds under high headspace pressures.
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Affiliation(s)
- David Valero
- Department of Water and Environmental Science and Technologies, University of Cantabria, Avda. Los Castros, s/n, 39005 Santander, Spain
| | - Jesús A Montes
- Department of Water and Environmental Science and Technologies, University of Cantabria, Avda. Los Castros, s/n, 39005 Santander, Spain
| | - José Luis Rico
- Department of Chemical and Process Engineering Resources, University of Cantabria, Avda. Los Castros, s/n, 39005 Santander, Spain
| | - Carlos Rico
- Department of Water and Environmental Science and Technologies, University of Cantabria, Avda. Los Castros, s/n, 39005 Santander, Spain.
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66
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Protocol for Start-Up and Operation of CSTR Biogas Processes. SPRINGER PROTOCOLS HANDBOOKS 2016. [DOI: 10.1007/8623_2016_214] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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67
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Steffen F, Requejo A, Ewald C, Janzon R, Saake B. Anaerobic digestion of fines from recovered paper processing - Influence of fiber source, lignin and ash content on biogas potential. BIORESOURCE TECHNOLOGY 2016; 200:506-513. [PMID: 26520490 DOI: 10.1016/j.biortech.2015.10.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 09/23/2015] [Accepted: 10/01/2015] [Indexed: 06/05/2023]
Abstract
Fines concentration harms paper machine runability and output quality in recovered paper processing, hence, their extraction would be fundamentally beneficial. In this study, separated fines from an industrial recycled fiber pulp (RFP) were characterized and evaluated for their potential biogas yields with a focus on understanding the role of varying lignin and ash contents. Further, these results were compared with biogas yields from conventional chemical and mechanical pulps. Overall, methane yields of fines from mechanical pulps (21-28mL/gVS) and RFP (127mL/gVS) are relatively low compared to the high methane yields of 375mL/gVS from the chemical pulp fines. However, it was shown that the high ash content in RFP fines (up to 50%) did not negatively influence overall yield, rather, it was the presence of slowly biodegrading lignin-rich fiber fines.
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Affiliation(s)
- Friedrich Steffen
- Chemical Wood Technology, Department of Wood Science, University of Hamburg, Leuschnerstr. 91B, 21031 Hamburg, Germany
| | - Ana Requejo
- Chemical Engineering Department, University of Córdoba, Building Marie-Curie, Campus of Rabanales, 14071 Córdoba, Spain
| | - Christian Ewald
- Department of Paper Technology and Mechanical Process Engineering, University of Darmstadt, Alexanderstr. 8, 64283 Darmstadt, Germany
| | - Ron Janzon
- Chemical Wood Technology, Department of Wood Science, University of Hamburg, Leuschnerstr. 91B, 21031 Hamburg, Germany
| | - Bodo Saake
- Chemical Wood Technology, Department of Wood Science, University of Hamburg, Leuschnerstr. 91B, 21031 Hamburg, Germany.
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68
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Moreda IL. Determining anaerobic degradation kinetics from batch tests. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2016; 73:2468-2474. [PMID: 27191569 DOI: 10.2166/wst.2016.110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Data obtained from a biomethane potential (BMP) test were used in order to obtain the parameters of a kinetic model of solid wastes anaerobic degradation. The proposed model considers a hydrolysis step with a first order kinetic, a Monod kinetic for the soluble organic substrate degradation and a first order decay of microorganisms. The instantaneous release of methane was assumed. The parameters of the model are determined following a direct search optimization procedure. A 'multiple-shooting' technique was used as a first step of the optimization process. The confidence interval of the parameters was determined by using Monte Carlo simulations. Also, the distribution functions of the parameters were determined. Only the hydrolysis first order constant shows a normal distribution.
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Affiliation(s)
- Iván López Moreda
- Facultad de Ingeniería, Universidad de la República, J. Herrera y Ressig 565, Montevideo, Uruguay E-mail:
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69
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Koch K, Plabst M, Schmidt A, Helmreich B, Drewes JE. Co-digestion of food waste in a municipal wastewater treatment plant: Comparison of batch tests and full-scale experiences. WASTE MANAGEMENT (NEW YORK, N.Y.) 2016; 47:28-33. [PMID: 25957939 DOI: 10.1016/j.wasman.2015.04.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 04/15/2015] [Accepted: 04/15/2015] [Indexed: 06/04/2023]
Abstract
The effects of co-digestion of food waste in a municipal wastewater treatment plant (WWTP) were studied in batch tests. The results obtained were compared with the mass balance of a digester at a full-scale WWTP for a one-year period without and with the addition of co-substrate. The specific methane yield calculated from the balance was 18% higher than the one in the batch tests, suggesting a stimulation of methane generation by co-digestion. It was hypothesized that this increase was caused by shifting the C/N ratio of raw sludge (8.8) to a more favourable ratio of the added food waste (17.7). In addition, potential benefits by adding food waste for energy autarky was investigated. While just 25% of the total energy demand of the plant could be recovered by biogas generation when no co-substrate was fed, this percentage has more than doubled when food waste was added at a ratio of 10% (w/w).
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Affiliation(s)
- Konrad Koch
- Chair of Urban Water Systems Engineering, Technische Universität München, Am Coulombwall 8, 85748 Garching, Germany.
| | - Markus Plabst
- Chair of Urban Water Systems Engineering, Technische Universität München, Am Coulombwall 8, 85748 Garching, Germany
| | - Andreas Schmidt
- Wastewater Treatment Plant Garching an der Alz, Berndlmühle 34, 84518 Garching an der Alz, Germany
| | - Brigitte Helmreich
- Chair of Urban Water Systems Engineering, Technische Universität München, Am Coulombwall 8, 85748 Garching, Germany
| | - Jörg E Drewes
- Chair of Urban Water Systems Engineering, Technische Universität München, Am Coulombwall 8, 85748 Garching, Germany
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70
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Sun L, Liu T, Müller B, Schnürer A. The microbial community structure in industrial biogas plants influences the degradation rate of straw and cellulose in batch tests. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:128. [PMID: 27330562 PMCID: PMC4912747 DOI: 10.1186/s13068-016-0543-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Accepted: 06/02/2016] [Indexed: 05/03/2023]
Abstract
BACKGROUND Materials rich in lignocellulose, such as straw, are abundant, cheap and highly interesting for biogas production. However, the complex structure of lignocellulose is difficult for microbial cellulolytic enzymes to access, limiting degradation. The rate of degradation depends on the activity of members of the microbial community, but the knowledge of this community in the biogas process is rather limited. This study, therefore, investigated the degradation rate of cellulose and straw in batch cultivation test initiated with inoculums from four co-digestion biogas plants (CD) and six wastewater treatment plants (WWTP). The results were correlated to the bacterial community by 454-pyrosequencing targeting 16S rRNA gene and by T-RFLP analysis targeting genes of glycoside hydrolase families 5 (cel5) and 48 (cel48), combined with construction of clone libraries. RESULTS UniFrac principal coordinate analysis of 16S rRNA gene amplicons revealed a clustering of WWTPs, while the CDs were more separated from each other. Bacteroidetes and Firmicutes dominated the community with a comparably higher abundance of the latter in the processes operating at high ammonia levels. Sequences obtained from the cel5 and cel 48 clone libraries were also mainly related to the phyla Firmicutes and Bacteroidetes and here ammonia was a parameter with a strong impact on the cel5 community. The results from the batch cultivation showed similar degradation pattern for eight of the biogas plants, while two characterised by high ammonia level and low bacterial diversity, showed a clear lower degradation rate. Interestingly, two T-RFs from the cel5 community were positively correlated to high degradation rates of both straw and cellulose. One of the respective partial cel5 sequences shared 100 % identity to Clostridium cellulolyticum. CONCLUSION The degradation rate of cellulose and straw varied in the batch tests dependent on the origin of the inoculum and was negatively correlated with the ammonia level. The cellulose-degrading community, targeted by analysis of the glycoside hydrolase families 5 (cel5) and 48 (cel48), showed a dominance of bacteria belonging the Firmicutes and Bacteriodetes, and a positive correlation was found between the cellulose degradation rate of wheat straw with the level of C. cellulolyticum.
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Affiliation(s)
- Li Sun
- />Department of Microbiology, Swedish University of Agricultural Science, Uppsala BioCenter, P.O. Box 7025, 750 07 Uppsala, Sweden
| | - Tong Liu
- />Department of Microbiology, Swedish University of Agricultural Science, Uppsala BioCenter, P.O. Box 7025, 750 07 Uppsala, Sweden
| | - Bettina Müller
- />Department of Microbiology, Swedish University of Agricultural Science, Uppsala BioCenter, P.O. Box 7025, 750 07 Uppsala, Sweden
| | - Anna Schnürer
- />Department of Microbiology, Swedish University of Agricultural Science, Uppsala BioCenter, P.O. Box 7025, 750 07 Uppsala, Sweden
- />Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Science, 1432 Ås, Norway
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71
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Wang B, Strömberg S, Nges IA, Nistor M, Liu J. Impacts of inoculum pre-treatments on enzyme activity and biochemical methane potential. J Biosci Bioeng 2015; 121:557-60. [PMID: 26526543 DOI: 10.1016/j.jbiosc.2015.10.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 09/07/2015] [Accepted: 10/05/2015] [Indexed: 11/30/2022]
Abstract
Biochemical methane potential (BMP) tests were carried out to investigate the influence of inoculum pre-treatments (filtration and pre-incubation) on methane production from cellulose and wheat straw. First-order model and Monod model were used to evaluate the kinetic constants of the BMP assays. The results demonstrated that fresh inoculum was the best option to perform BMP tests. This was evidenced by highest enzyme activity (0.11 U/mL) and highest methane yields for cellulose (356 NmL CH4/gVS) as well as wheat straw (261 NmL CH4/gVS). Besides, high biodegradability (85.8% for cellulose and 61.3% for wheat straw) was also obtained when the fresh inoculum was used. Moreover, a kinetic evaluation showed that inoculum pre-incubation at 37°C or storage at 4°C introduced a lag-time whereas the effects on hydrolysis rate were less consequent. In summary, pre-treatments affected the enzyme activity of the inoculum, and further on, significantly influenced the methane production and the degradation kinetics of the investigated substrates. It is recommended that filtration of inoculum should be avoided unless in case too large particles therein.
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Affiliation(s)
- Bing Wang
- Department of Biotechnology, Lund University, Getingevägen 60, SE-221 00 Lund, Sweden.
| | - Sten Strömberg
- Department of Biotechnology, Lund University, Getingevägen 60, SE-221 00 Lund, Sweden
| | - Ivo Achu Nges
- Department of Biotechnology, Lund University, Getingevägen 60, SE-221 00 Lund, Sweden
| | - Mihaela Nistor
- Bioprocess Control Sweden AB, Scheelevägen 22, SE-223 63 Lund, Sweden
| | - Jing Liu
- Department of Biotechnology, Lund University, Getingevägen 60, SE-221 00 Lund, Sweden; Bioprocess Control Sweden AB, Scheelevägen 22, SE-223 63 Lund, Sweden
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72
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Koch K, Bajón Fernández Y, Drewes JE. Influence of headspace flushing on methane production in Biochemical Methane Potential (BMP) tests. BIORESOURCE TECHNOLOGY 2015; 186:173-178. [PMID: 25817027 DOI: 10.1016/j.biortech.2015.03.071] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2015] [Revised: 03/13/2015] [Accepted: 03/14/2015] [Indexed: 06/04/2023]
Abstract
The influence of headspace flushing on the specific methane (CH4) production of blank samples with just inoculum in Biochemical Methane Potential (BMP) tests was studied. The three most common ways were applied: flushing with nitrogen (N2) gas, flushing with a mixture of N2 and CO2 (80/20 v/v), and no flushing. The results revealed that removing the oxygen is crucial to avoid aerobic respiration, which caused both hindered activity of methanogens and loss of methane potential. Furthermore it was demonstrated that 20% of CO2 in the flush gas increased significantly the methane production by over 20% compared to the flushing with pure N2. In order to mimic the same headspace conditions as in full-scale treatment plants, using a flush gas with a similar CO2 concentration as the expected biogas is suggested.
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Affiliation(s)
- Konrad Koch
- Chair of Urban Water Systems Engineering, Technische Universität München, Am Coulombwall 8, 85748 Garching, Germany.
| | - Yadira Bajón Fernández
- Cranfield Water Science Institute, School of Applied Sciences, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK
| | - Jörg E Drewes
- Chair of Urban Water Systems Engineering, Technische Universität München, Am Coulombwall 8, 85748 Garching, Germany
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73
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Strömberg S, Nistor M, Liu J. Early prediction of Biochemical Methane Potential through statistical and kinetic modelling of initial gas production. BIORESOURCE TECHNOLOGY 2015; 176:233-241. [PMID: 25461008 DOI: 10.1016/j.biortech.2014.11.033] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 11/06/2014] [Accepted: 11/08/2014] [Indexed: 06/04/2023]
Abstract
A major drawback of Biochemical Methane Potential (BMP) tests is their long test duration, which could be reduced substantially if the final gas production could be predicted at an earlier stage. For this purpose, this study evaluates 61 different algorithms for their capability to predict the final BMP and required degradation time based on data from 138 BMP tests of various substrate types. By combining the best algorithms it was possible to predict the BMP with a relative root mean squared error (rRMSE) of less than 10% just 6days after initiation of the experiment. The results from this study indicate that there is a possibility to shorten the test length substantially by combining laboratory tests and intelligent prediction algorithms. Shorter test duration may widen the possible applications for BMP tests in full-scale biogas plants, allowing for a better selection and proper pricing of biomass.
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Affiliation(s)
- Sten Strömberg
- Department of Biotechnology, Lund University, Getingevägen 60, 221 00 Lund, Sweden.
| | - Mihaela Nistor
- Bioprocess Control AB, Scheelevägen 22, 223 63 Lund, Sweden.
| | - Jing Liu
- Department of Biotechnology, Lund University, Getingevägen 60, 221 00 Lund, Sweden; Bioprocess Control AB, Scheelevägen 22, 223 63 Lund, Sweden.
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