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 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 Kinetic Modeling and Experimentation of Anaerobic Digestion written by Jonathan E. Rea and published by . This book was released on 2014 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: Anaerobic digesters convert organic waste (agricultural and food waste, animal or human manure, and other organic waste), into energy (in the form of biogas or electricity). An added benefit to bio-digestion is a leftover high-grade organic fertilizer. Models of the anaerobic digestion process do exist, but either rely on simple algebraic equations instead of biochemical reactions, or consider so many external parameters that they become overly complicated and require much input information and computation time. This work provides an intermediate kinetic model that predicts biogas output over time with few inputs. This kinetic model is justified by a small-scale laboratory experiment, and parameters are adjusted to match experimental results. This model can be used to optimize design parameters for an anaerobic digester, and provides information such as the relationship between digester sizing and feed rate. The process used here may be expanded to other feedstock materials and repeated for other similar applications, in an effort to expand anaerobic digestion systems as a clean energy source.

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 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 The Microbiology of Anaerobic Digesters written by Michael H. Gerardi and published by John Wiley & Sons. This book was released on 2003-09-19 with total page 189 pages. Available in PDF, EPUB and Kindle. Book excerpt: Anaerobic digestion is a biochemical degradation process that converts complex organic material, such as animal manure, into methane and other byproducts. Part of the author's Wastewater Microbiology series, Microbiology of Anareboic Digesters eschews technical jargon to deliver a practical, how-to guide for wastewater plant operators.

Download or read book Selected Water Resources Abstracts written by and published by . This book was released on 1988 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bio methanation Tests and Mathematical Modelling to Assess the Role of Moisture Content on Anaerobic Digestion of Organic Waste written by Flavia Liotta and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dry Anaerobic Digestion (AD) presents different advantages if compared to wet AD, i.e. smaller reactor size, lesser water addition, digestate production and pretreatment needed, although several studies have demonstrated that water promotes substrate hydrolysis and enables the transfer of process intermediates and nutrients to bacterial sites. To better understand the role of water on AD, dry and semidry digestion tests of selected complex organic substrates (food waste, rice straw, carrot waste), with various TS contents of the treated biomass have been carried out in the present study. The results confirm that water plays an essential role on the specific methane production rate, final methane yield and Volatile Solids (VS) degradation. The final methane yield in semi-dry and dry conditions was 51% and 59% lower for rice straw and 4% and 41% lower for food waste, respectively, if compared with wet conditions. Inhibition tests, based on Volatile Fatty Acid (VFA) analysis, were carried out to investigate the specific inhibition processes that take place with the selected substrates at different TS contents. In wet AD of carrot waste no VFA accumulation was found, and all VFA concentrations were lower than the inhibition limits. A direct correlation between TS content and total VFA (TVFA) concentration was noticed for rice straw and food waste AD. For rice straw a maximum TVFA concentration of 2.1 g/kg was found in dry condition, 1 g/kg in semidry conditions and 0.2 g/kg in wet conditions, whereas for food waste the TVFA concentration was 10 g/kg in dry condition, 9 g/kg in semidry conditions and 3 g/kg in wet conditions. A Mathematical model of complex organic substrate AD in dry and semidry conditions has been proposed to simulate the effect of TS content on the process. The data obtained from batch experiments, in terms of methane production and VFA concentrations, were used to calibrate the proposed model. The kinetic parameters of VFA production and degradation, calibrated using the experimental data, resulted highly dependent on the TS content and different from wet AD literature values. This is due to VFA accumulation in dry conditions, which implies higher values of the inhibition factors introduced in the model. Finally, as dry AD takes usually place in Plug Flow (PF) reactors, an historical and critical review on the role of hydrodynamics in PF bioreactors has been carried out.

Download or read book Anaerobic Digestion Processes written by Nigel Horan and published by Springer. This book was released on 2018-04-18 with total page 187 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents new application processes in the context of anaerobic digestion (AD), such as phosphorus recovery, microbial fuel cells (MFCs), and seaweed digestion. In addition, it introduces a new technique for the modeling and optimization of AD processes. Chapters 1 and 2 review AD as a technique for converting a range of organic wastes into biogas, while Chapter 3 discusses the recovery of phosphorus from anaerobically digested liquor. Chapters 4 and 5 focus on new techniques for modeling and optimizing AD. Chapters 6 and 7 then describe the state of the art in AD effluent treatment. The book’s final three chapters focus on more recent developments, including microbial fuel cells (MFCs) (Chapter 8), seaweed production (Chapter 9), and enzyme technologies (Chapter 10).

Download or read book Continuous Anaerobic Digestion of High Solids Biomass written by Robert Legrand and published by . This book was released on 1983 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Simulation of Flow Mass Transfer and Bio chemical Reactions in Anaerobic Digestion written by Liang Yu (dd) and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The mechnisim of a high rate digestor was explored by a multi-fluid model with KTGF. The simulation results suggest that the dairy manure particles tend to have soft and deformable fluid properties due to the lower contribution of collisional and kinetic components. The evaluation for biomass retention allowed the determination of the optimum SRT in anaerobic digestion. Aided with CFD simulation, the scale-up effect of the hydrodynamic nature from the bottle reactor to the column reactor was reduced.

Download or read book ERDA Energy Research Abstracts written by and published by . This book was released on 1989 with total page 848 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fossil Energy Update written by and published by . This book was released on 1981 with total page 886 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energy Research Abstracts written by and published by . This book was released on 1990 with total page 840 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Kinetics of Anaerobic Purification of Organic Wastes written by Alan Joseph Shuckrow and published by . This book was released on 1963 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 A Study of High Solids Anaerobic Digestion of Bucknell University Food Waste Followed by Aerobic Curing written by Margaret F. Drennan and published by . This book was released on 2011 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: To determine the suitability of food waste produced at Bucknell for high-solids anaerobic digestion (HSAD), a year-long characterization study was conducted. Physical and chemical properties, waste biodegradability, and annual production of biodegradable waste were assessed. Bucknell University food and landscape waste was digested at pilot-scale for over a year to test performance at low and high loading rates, ease of operation at 20% solids, benefits of codigestion of food and landscape waste, and to provide digestate for studies to assess the curing needs of HSAD digestate. A laboratory- scale curing study was conducted to assess the curing duration required to reduce microbial activity, phytotoxicity, and odors to acceptable levels for subsequent use of humus.