Download or read book The Anaerobic Digestion of Organic Solid Wastes of Variable Composition written by Nigel Gareth Hugh Guilford and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract Every year in Canada approximately 8 million tonnes of organic solid waste is placed in landfills where it decomposes anaerobically over decades, produces large volumes of leachate requiring treatment, and releases 20 million tonnes of greenhouse gas emissions as CO2eq. Anaerobically digesting this waste prior to landfill would obviously be beneficial, but this is difficult to achieve because solid waste is a complex, heterogeneous and variable mixture, making any form of processing much more expensive than landfill. This thesis investigates the capabilities of a new approach to the anaerobic digestion of solid waste designed to overcome these obstacles. Most of the costly separation and pretreatment steps common in European anaerobic digesters are eliminated. The waste remains stationary, the leachate is recirculated through it, and the resulting digestate is aerobically cured. The biogas generated is recovered for the generation of electricity or the production of renewable natural gas. A laboratory scale system comprising six sequentially batch fed leach beds and an upflow anaerobic sludge blanket reactor was constructed, and operated continuously for 616 days. The feedstock consisted of a mixture of cardboard, boxboard, newsprint, and fine paper, to which varying amounts of food waste were added (from 0% to 29% on a COD basis). The digester accommodated these and other changes without any signs of process upset or instability. It was found that the addition of food waste increased biogas production from the fibre mixture from 101 L.kg-1CODfibreadded to 330 L. kg-1CODfibreadded an increase of 225%. A substrate destruction efficiency of 65% (on a COD basis) and a methane yield of 225 L.kg-1 CODadded were achieved, at a solids retention time of 42 days. This performance was similar to that of a CSTR digesting similar wastes. A financial analysis showed that the technology can be competitive with landfill.
Download or read book Anaerobic Digestion Model No 1 ADM1 written by IWA Task Group for Mathematical Modelling of Anaerobic Digestion Processes and published by IWA Publishing. This book was released on 2002-02-01 with total page 61 pages. Available in PDF, EPUB and Kindle. Book excerpt: The IWA Task Group for Mathematical Modelling of Anaerobic Digestion Processes was created with the aim to produce a generic model and common platform for dynamic simulations of a variety of anaerobic processes. This book presents the outcome of this undertaking and is the result of four years collaborative work by a number of international experts from various fields of anaerobic process technology. The purpose of this approach is to provide a unified basis for anaerobic digestion modelling. It is hoped this will promote increased application of modelling and simulation as a tool for research, design, operation and optimisation of anaerobic processes worldwide. This model was developed on the basis of the extensive but often disparate work in modelling and simulation of anaerobic digestion systems over the last twenty years. In developing ADM1, the Task Group have tried to establish common nomenclature, units and model structure, consistent with existing anaerobic modelling literature and the popular activated sludge models (See Activated Sludge Models ASM1, ASM2, ASM2d and ASM3, IWA Publishing, 2000, ISBN: 1900222248). As such, it is intended to promote widespread application of simulation from domestic (wastewater and sludge) treatment systems to specialised industrial applications. Outputs from the model include common process variables such gas flow and composition, pH, separate organic acids, and ammonium. The structure has been devised to encourage specific extensions or modifications where required, but still maintain a common platform. During development the model has been successfully tested on a range of systems from full-scale waste sludge digestion to laboratory-scale thermophilic high-rate UASB reactors. The model structure is presented in a readily applicable matrix format for implementation in many available differential equation solvers. It is expected that the model will be available as part of commercial wastewater simulation packages. ADM1 will be a valuable information source for practising engineers working in water treatment (both domestic and industrial) as well as academic researchers and students in Environmental Engineering and Science, Civil and Sanitary Engineering, Biotechnology, and Chemical and Process Engineering departments. Contents Introduction Nomenclature, State Variables and Expressions Biochemical Processes Physicochemical Processes Model Implementation in a Single Stage CSTR Suggested Biochemical Parameter Values, Sensitivity and Estimation Conclusions References Appendix A: Review of Parameters Appendix B: Supplementary Matrix Information Appendix C: Integration with the ASM Appendix D: Estimating Stoichiometric Coefficients for Fermentation Scientific & Technical Report No.13
Download or read book Anaerobic Digestion of Organic Solid Waste for Energy Production written by Satoto Endar Nayono and published by KIT Scientific Publishing. This book was released on 2010 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: Anaerobic digestion of the organic fraction of municipal solid waste as such or together with food waste, press water or patatoes sludge was investigated to equilibrate methane production within a day or over the weekend, when no OFMSW was available. A stable co-digestion process could be achieved with COD degradation between 60 and 80 %. The max. organic loading rates were 28 kg COD/L, d. For stable methane production the OLR during Co-digestion should not excede 22,5 kg/L,
Download or read book Biomethanization of the Organic Fraction of Municipal Solid Wastes written by J. Mata-Alvarez and published by IWA Publishing. This book was released on 2002-08-31 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biomethanization of the Organic Fraction of Municipal Solid Wastes is a comprehensive introduction to both the fundamentals and the more practical aspects of the anaerobic digestion of organic solid wastes, particularly those derived from households, that is, the organic fraction of municipal solid wastes (OFMSW). It can be used as a textbook for specialized courses and also as a guide for practitioners. In the first part, the book covers the relevant aspects of anaerobic digestion (AD) of organic wastes. The fundamentals and kinetic aspects of AD are reviewed with particular emphasis on the aspects related to solid wastes. This introduction is necessary to have a comprehensive view of the AD process and to understand the practical principles as well as the origin of possible problems arising from the management of the process. Chapter 2 emphasizes the role of kinetics in designing the reactor, paying special attention to existing models, particularly the dynamic ones. Through this introduction, it is intended to facilitate the technology transfer from laboratory or pilot plant experiences to full-scale process, in order to implement improvements in current digesters. Laboratory methods are described for the analysis and optimization of reactor performance, such as methanogenic activity tests or experimental evaluation of the biodegradation kinetics of solid organic waste. The different reaction patterns applied to industrial reactors are outlined. Industrial reactors are classified in accordance with the system they use, pointing out advantages and limitations. Co-digestion, enabling the co-treatment of organic wastes of different origin in a more economically feasible way, is described in detail. Examples of co-digestion are given, with OFMSW as a base-substrate. Finally, full-scale co-digestion plants are discussed. Various types (mechanical, biological, physico-chemical) of pre-treatment to increase the biodegradability, and thus the yields of the process, are reviewed in detail. The use of the fermentation products of anaerobic digesters for biological nutrient removal processes in wastewater treatment plants is described. This constitutes an example of integrated waste management, a field in which both economic and technical advances can be achieved. Balances are given to justify the approach, and a full-scale case study is presented. The important topic of economics and the ecological advantages of the process are emphasized. The use of compost, the integration with composting technology, and advantages over other technologies are detailed in the framework of an environmental impact assessment of biowaste treatment. Finally, the anaerobic digestion of MSW in landfills is reviewed in detail, with emphasis on landfill process enhancement and strategies for its application.
Download or read book Anaerobic Digestion of Organic Solid Waste written by Fernando G. Fermoso and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the years, research on the anaerobic digestion of solid waste has mainly focused on single feedstocks with a fixed composition. Nevertheless, the impact assessment that drastic changes in the type and composition of feedstock might have on AD process stability has not been investigated in depth. The existence of a wide variety of organic solid waste whose generation and composition are highly dependent on seasonality, just as the possibility of using treatment plant facilities already in operation for treating new waste, makes it necessary to improve our knowledge of transitory states in AD. This chapter aims to provide insight into research on transitory states during the AD process when the type or composition of the feedstock has suffered a change to assess whether the AD process was finally able to adapt to system disturbances. Information about process stability control and microbial population adaptation, among others, derived from the transition states will be addressed.
Download or read book Anaerobic Digestion of Classified Municipal Solid Wastes written by and published by . This book was released on 1981 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Anaerobic Digestion of Organic Solid Waste for Energy Production written by Satoto Endar Nayono and published by . This book was released on 2009 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Anaerobic Digestion of Organic Waste written by Charles Sendaaza and published by . This book was released on 2018 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Rapid population growth, urbanization, improved living standards and a shift in the consumption patterns have accordingly escalated the intensity of waste generation. The 2012 World Bank report on solid waste estimated the annual municipal solid waste generation at 1.3 billion tons per year with a projection of over a 40% increase in the annual generation rate by 2025 and a 300% increase by 2100 worldwide. Nearly half of the generated municipal solid waste is organic, including food wastes. About 30% of the food produced annually is wasted at different stages along the food supply chain before human consumption. Kitchens serving the food needs of The American University in Cairo’s New campus haven’t performed any different in their yield of food waste, with on campus kitchens producing up to 150kg of food waste, mainly a composition of fruit and vegetable waste daily. Agricultural development mainly driven by extensive mechanization, continued incentivization and growing demand for food on the other hand is also a significant organic waste generator. Recent data estimates the annual production of agricultural waste at close to 1000 million tons. Animal and poultry wastes in form of manure have been reported by different researchers for their negative environmental impacts resulting from their direct application in agriculture or mismanagement, raising concern over possible alternative means of sustainable management. Anaerobic digestion stands out as the most viable means of sustainable management thanks to the high moisture content and nutrient composition of the manures. This study carried out in two phases aimed at investigating anaerobic digestion of the American University in Cairo’s kitchen waste, market vegetable waste and animal and chicken manure. In Phase I of the experiment, batch setups of 100% animal manure (A), 100% chicken manure (B), 1:1 animal to chicken manure (C) and 1:4 animal to market vegetable waste (D) were digested for nine weeks. Biogas yield at the end of digestion was 285.33L, 300.54L, 329.95L and 0.00L respectively. Average methane composition in digesters A, B and C was 43.54%, 52.59% and 45.58% respectively. Phase II of the experiment was exclusive to The American University in Cairo’s kitchen waste. Three batch set ups; KW1, KW2 and KW3 of uniform amounts of kitchen waste were prepared. KW1 was inoculated with digested animal manure from A, KW2 with digested chicken manure from B and KW3 inoculated with Chinese bokashi. Results of accumulated biogas yield at the end of a six weeks’ psychrophilic digestion period were in the order KW2 > KW3 > KW1; 498.64L, 284.58L, and 65.54L respectively. Average methane composition was 41.63%, 40.33% and 25.55% in KW3, KW2 and KW1 respectively. Following confirmation of the biological feasibility of anaerobic digestion of the University’s kitchen waste, technical and economic studies make the project even a more daring venture for the university’s engagement. A biogas production project satisfactorily blends into the university’s sustainability goals with the potential to offset up to an equivalent of over 4% of the CO2 emissions from the combustion of natural gas for on campus domestic and lab purposes. The many strengths and opportunities listed in the SWOT analysis of the project make it a viable step towards sustainable development. However, the noted weaknesses and threats demand for close collaboration of the University’s offices overseeing food services, campus sustainability, landscape, and facilities and operation with technical help from the Center for Sustainable Development and the Research Institute for a Sustainable Environment if the project is to come to life.
Download or read book Anaerobic Digestion of Solid Waste written by F. Cecchi and published by IWA Publishing (International Water Assoc). This book was released on 1993-05-31 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is no description available for this title
Download or read book Anaerobic Digestion of Solid Waste and Sewage Sludge to Methane written by Steven J. Hitte and published by . This book was released on 1975 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Methane Production from Agricultural and Domestic Wastes written by Hobson and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 343 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume in the Energy from Wastes Series covers the area of methane production from agricultural and domestic wastes. Principally this involves the conversion of excreta and other organic effluents to a valuable gaseous fuel plus, in many cases, a useful sludge for fertiliser or feedstuffs. Dr Hobson and his colleagues have written a comprehensive text on the principles of microbiological processes and the biochemistry of anaerobic digestion, embracing the design of digesters with examples of current working installations. The potential for anaerobic digestion of wastes as diverse as sewage to fruit processing effluents is also reviewed. This work should be of interest to all who have to manage organic waste treatment and disposal, as well as to a wider readership who wish to know more about methane production by anaerobic digestion. ANDREW PORTEOUS v Preface The production of methane, or more exactly, a flammable 'biogas' containing methane and carbon dioxide, by microbiological methods ('anaerobic digestion') is not new. The reactions have been in industrial use for over a hundred years, but only in sewage purification processes. In some times of national stress, such as war-time, the microbiological production of gas purely for fuel has been investigated, but with the resumption of plentiful su pplies of fossil fuels the investigations have faded awa y.
Download or read book Anaerobic Digestion of Solid Waste II written by J. Mata-Alvarez and published by IWA Publishing (International Water Assoc). This book was released on 2000-05-31 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the last decade much progress has been made in anaerobic digestion of solid waste: advances in research and development, construction of new plants, more favourable legislation. Key features of this progress are reported in these proceedings. While the selected papers cover a wide range of work on 'solid' organic wastes, there is a particular focus on the organic fraction of Municipal Solid Waste (MSW). Many landfills are set to close and there is a significant increase in separate collection of MSW. Biological treatments can maximise recycling and recovery of its components; anaerobic digestion, with its high energy recovery and limited environmental impact, is frequently the most cost-effective of these treatments. The future of anaerobic digestion of solid wastes is increasingly seen in the integration of this unique unit process in overall sustainable waste treatment. In Life Cycle Analysis anaerobic digestion offers several interesting features: energy recovery (a particularly important factor in third world countries); and a significantly lower contribution to global warming. Problems remain (as for all types of wastes treatments), particularly concerning the fate of micro-pollutants and overall end-product quality, but anaerobic digestion offers major potential in the long-term environmental management. These proceedings offer an unrivalled authoritative view of the present and future of anaerobic digestion of solid waste.
Download or read book Experimental and Modeling Assessment of the Main Bio physical chemical Mechanisms and Kinetics in High solids Anaerobic Digestion of Organic Waste written by Vicente Pastor Poquet and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The organic fraction of municipal solid waste (OFMSW) includes readily biodegradable wastes such as food waste, and slowly biodegradable wastes such as lignocellulosic materials. Anaerobic digestion (AD) is a mature treatment biotechnology in which OFMSW is decomposed to a mixture of methane (CH4) and carbon dioxide (CO2), known as biogas. Due to the elevated CH4 content (50-70%), biogas can be used as a source of renewable energy. Moreover, AD yields a partially stabilized digestate, allowing the recycle of nutrients to agriculture. High-solids anaerobic digestion (HS-AD) is a well-suited strategy to enhance the overall AD efficiency for OFMSW treatment. HS-AD is operated at a total solid (TS) content ≥ 10%, permitting to reduce the reactor size and overall operational costs. Nonetheless, the TS increase can result into biochemical instability, and even reactor failure by acidification. Both the high organic load and the buildup of inhibitors can be responsible for the HS-AD instability. The most notable inhibitor in HS-AD of OFMSW is NH3. Therefore, a balance is often required between enhancing the HS-AD economy and the 'undesired' instability for OFMSW treatment. This PhD research investigated the main bio-physical-chemical mechanisms and kinetics in HS-AD of OFMSW, with the aim to optimize the industrial application and maximize the kinetic rates. Laboratory-scale batch and semi-continuous experiments highlighted the main strengths and weaknesses of HS-AD. Simultaneously, the development of a HS-AD model permitted to condense the experimental knowledge about the bio-physical-chemical effects occurring when increasing the TS content in HS-AD.HS-AD batch experiments required a tradeoff between the initial TS, the inoculum-to-substrate ratio (ISR), the alkalinity and the nitrogen content, to assess the effects of increasing the initial TS content upon the methane yield, TS removal and chemical oxygen demand conversion. Particularly, a low ISR led to acidification, whereas the NH3 buildup led to volatile fatty acid (VFA) accumulation, reducing the methane yield, whether or not co-digestion of OFMSW with beech sawdust was used.In semi-continuous experiments, HS-AD of OFMSW required a reduced effluent compared to the influent to counterbalance the organic mass removal associated to the biogas production. Nonetheless, mono-digestion of readily-biodegradable OFMSW could not sustain a TS ≥ 10% without exacerbating the risk of substrate overload. Overloading was associated to the high biodegradability and the NH3 buildup. Thus, adding sawdust to OFMSW permitted to operate the reactors up to 30% TS, due to the lower biodegradability and nitrogen content of lignocellulosic substrates. As the main novelty of this PhD research, a HS-AD model based on the Anaerobic Digestion Model No.1 (ADM1) was developed. This model simulates the reactor mass and TS in HS-AD, in contrast of models focusing on 'wet' AD simulations (TS
Download or read book Thermophilic Digestion of Municipal Organic Solid Waste in an Anaerobic Phased Solids Digester System written by Willus B. Withrow and published by . This book was released on 2006 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of Anaerobic Digestion Process for Derived MBT Organic Solid Wastes written by M. Arsand and published by . This book was released on 2008 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Anaerobic Digestion of Organic Fraction of Municipal Solid Wastes written by Lucia Martín González and published by . This book was released on 2011 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Anaerobic Digestion of Food and Vegetable Waste written by Ying Jiang and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Food and vegetable wastes contribute a large percentage of the organic fraction of municipal solid waste (OFMSW), and anaerobic digestion potentially offers an ideal method for their management. Their chemical composition can, however, lead to unstable operation and in extreme cases complete process failure has been reported with this type of substrate. Semi-continuous trials on vegetable waste were carried out in laboratory-scale digesters with daily feed additions at different organic loading rates (OLR). At an OLR of 2g volatile solids (VS) 1-1 day-1 the methane yield was 0.345 1g-1 VS added, or 99% of that found in a biochemical methane potential (BMP) test. Higher OLRs led to reduced methane yield and energy conversion efficiency and to a drop in digester pH which could not be effectively controlled by alkali additions. To maintain digester stability it was necessary to supplement with additional trace elements including tungsten, which allowed OLR of up to 4g VS 1-1 day-1 to be achieved. Stability was also improved by the addition of yeast extract (YE). Co-digestion with card packaging and cattle slurry proved an effective means of restoring and maintaining stable operating conditions. Digesters fed on source segregated domestic food waste showed a long term pattern of failure as a result of the build-up of ammonia in the digester and the accumulation of volatile fatty acids, in particular propionic acid. The research gathered evidence to link this to an enzyme deficiency which was caused by a lack of selenium, or possibly other trace elements. Results from a fractional factorial designed batch experiment showed the importance of Se in the degradation of propionic acid, and indicated that Mo and Co might also play a role in this respect. Semi-continuous trials using laboratory-scale digesters also confirmed the requirement for Se which proved to be essential for both propionate oxidation and syntrophic hydrogenotrophic methanogenesis. Supplementation with Se allowed the digesters to operate at substantially higher OLR. At high loadings cobalt also becomes limiting, due to its role either in acetate oxidation in a reverse Wood-Ljungdahl pathway or in hydrogenotrophic methanogenesis. Critical Se and Co concentrations were established as 0.16 and 0.22mg kg-1 fresh matter feed at moderate loading. At this dosage the OLR could be raised to 5g VS 1-1 day-1 with specific and volumetric biogas productions of 0.75m3 kg-1 VS added and 3.75m3 m-3 day-1 at a standard temperature and pressure (STP) of 0°C and 101.325 kPa, representing a significant increase in process performance and operational stability. A tracer experiment using a radio-labelled isotope [2-14C] of acetate proved that under high ammonia concentrations, hydrogenotrophic methanogenesis was the dominant pathway leading to methane production in food waste digesters. A rapid non-derivatisation gas chromatographic method for quantification of palmitic, stearic and oleic acids was developed. These long chain fatty acids (LCFA) can accumulate in anaerobic digesters, and a simple extraction method was also developed to permit a more rapid sample turn-around time. The method was tested on digestate from food waste digesters. It was observed that the concentrations of stearic and palmitic acid in digesters routinely supplemented with trace elements were proportionally lower with respect to their relative loading when compared to those without supplementation. It was concluded that both Se and Co were deficient in source segregated domestic food waste collected in the UK, and that supplementation with these elements could improve digestion stability, allow higher OLR to be applied, and in doing so improve the energy yield of the digestion process.
