This book focuses on biogas production by anaerobic digestion, which is the most popular bioenergy technology of today. Using anaerobic digestion for the production of biogas is a sustainable approach that simultaneously also allows the treatment of organic waste. The energy contained in the substrate is released in the form of biogas, which can be employed as a renewable fuel in diverse industrial sectors. Although biogas generation is considered an established process, it continues to evolve, e.g. by incorporating modifications and improvements to increase its efficiency and its downstream applications. The chapters of this book review the progress made related to feedstock, system configuration and operational conditions. It also addresses microbial pathways utilized, as well as storage, transportation and usage of biogas. This book is an up-to-date resource for scientists and students working on improving biogas production.
Written as a practical introduction to biogas plant design and operation, this book fills a huge gap by presenting a systematic guide to this emerging technology -- information otherwise only available in poorly intelligible reports by US governmental and other official agencies. The author draws on teaching material from a university course as well as a wide variety of industrial biogas projects he has been involved with, thus combining didactical skill with real-life examples. Alongside biological and technical aspects of biogas generation, this timely work also looks at safety and legal aspects as well as environmental considerations.
Reap the benefits of sludge The processing of wastewater sludge for use or disposal has been a continuing challenge for municipal agencies. Yet, whensludge is properly processed, the resulting nutrient-rich product--biosolids--can be a valuable resource for agriculture and other uses. Wastewater Sludge Processing brings together a wide body of knowledge from the field to examine how to effectively process sludge to reap its benefits, yet protect public health. Presented in a format useful as both a reference for practicing environmental engineers and a textbook for graduatestudents, this book discusses unit operations used for processing sludge and the available methods for final disposition of the processed product. Topics discussed include sludge quantities and characteristics, thickening and dewatering, aerobicand anaerobic digestion, alkaline stabilization, composting, thermal drying and incineration, energy consumption, and the beneficial use of biosolids. COMPREHENSIVE IN ITS COVERAGE, THE TEXT: * Describes new and emerging technologies as well as international methods * Compares different types of sludge processing methods * Explains both municipal and industrial treatment technologies Written by authors with decades of experience in the field, Wastewater Sludge Processing is an invaluable tool for anyone planning, designing, and implementing municipal wastewater sludge management projects.
The global demand for energy is met mainly by fossil fuels. Their excessive and indiscriminate use, coupled with increasing demand for energy, will soon deplete their existing reserves. Therefore, it is extremely important to find alternative, environment-friendly, and ecologically sound sources of energy for meeting the present and future energy requirements. Biogas Technology: Towards Sustainable Development makes an attempt to explore the potential of utilizing biodegradable biomass as fuel and manure.
It is necessary to understand the extent of pollution in the environment in terms of the air, water, and soil in order for both humans and animals to live healthier lives. Poor waste treatment or pollution monitoring can lead to massive environmental issues, such as diminishing valuable resources, and cause a significant negative impact on society. Solutions, such as reuse of waste and sustainable waste management, must be explored to prevent these adverse effects. The Handbook of Research on Resource Management for Pollution and Waste Treatment is a collection of innovative research that examines waste and pollution treatment methods that can be adopted at local and international levels and examines appropriate resource management strategies for environmentally related issues. Featuring coverage on a wide range of topics such as soil washing, bioremediation, and runoff handling, this book is ideally designed for environmentalists, engineers, waste management professionals, natural resource regulators, environmental policymakers, scientists, academicians, researchers, and students seeking current research on viable resource management methods for the regeneration of their immediate environment.
Anaerobic digestion processes for the treatment of wastewaters and sludges are well over 100 years old. The anaerobic process is a natural gasification process, producing very useful end-products. It has taken a long time to prove that these processes are useful tools in sustainable development. A breakthrough was the development of the Upflow Anaerobic Sludge Bed reactor by Professor Gatze Lettinga. This showed that the anaerobic process could be operated as a highly effective and high-rate wastewater treatment process, opening the way to its implementation under practical conditions. It has, so far, been a struggle to prove the feasibility of anaerobic treatment, despite the obvious advantages in energy consumption, sludge production, and required land area; its drawbacks, i.e. required effluent polishing, odours, sensitivity to toxic compounds, made potential users reluctant to choose anaerobic instead of the conventional aerobic systems. However, as shown by the contributions in this issue, intensive research has overcome most of these drawbacks. To celebrate the career of Professor Lettinga, leading experts on anaerobic digestion processes were invited to highlight the state-of-the-art and future developments in their specific fields of interest. Seminar topics included microbiology, treatment of industrial wastewaters, xenobiotics and extreme environments, the biological S-cycle, treatment of domestic wastewater and the history of anaerobic digestion. The selected 20 papers in these proceedings represent the state of the art of anaerobic digestion, highlighting its impacts and potentials. They also recognised the stimulating role of Professor Gatze Lettinga in this development and agree with him that anaerobic digestion's full potential is still unexploited.
Intended to assist engineers, government officials and funding agencies to meet present and future challenges and make decisions on the promotion of anaerobic digestion as an alternative source of energy.
This book presents a Two-Stage Anaerobic Digestion (TSAD) technique for producing hydrogen and methane, following a step-by-step approach in order to guide readers through the experimental verification of the related hypothesis. In the first stage of AD, the reaction conditions are optimized to obtain the maximum amount of hydrogen, while in the second the liquid residue from the first phase is used as a substrate to produce fuel-methane. AD has traditionally been used to reduce the organic content of waste; this results in a biogas that is primarily constituted of CH4 and CO2. Over the last few decades, the conversion of organic matter into hydrogen by means of AD and selecting Hydrogen Producing Bacteria (HPB) has matured into a viable and sustainable technology among the pallet of H2 generation technologies. The combined bio-production of hydrogen and methane from Organic Waste Materials (OWM) is considered to be an ideal way of utilizing waste, and can increase energy efficiency (the substrate Heat Value converted into H2 and CH4 fuel) to roughly 80%, since the energy efficiency of H2-production alone (15%) is not energetically competitive. The two gas streams can be used either separately or in combination (Hytane®), be supplied as civilian gas or used for transportation purposes. All the aspects of this sustainable technology are taken into account, from the basic biochemical implications to engineering aspects, establishing the design criteria and the scale-up procedures for full-scale application. The sustainability of the TSAD method is assessed by applying EROI (Energy Return On Investment) and EPT (Energy Payback Time) criteria, and both the general approach and application to the field of Anaerobic Digestion are illustrated.
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.
Interest in anaerobic digestion (AD), the process of energy production through the production of biogas, has increased rapidly in recent years. Agricultural and other organic waste are important substrates that can be treated by AD. This book is one of the first to provide a broad introduction to anaerobic digestion and its potential to turn agricultural crops or crop residues, animal and other organic waste, into biomethane. The substrates used can include any non-woody materials, including grass and maize silage, seaweeds, municipal and industrial wastes. These are all systematically reviewed in terms of their suitability from a biological, technical and economic perspective. In the past the technical competence and high capital investment required for industrial-scale anaerobic digesters has limited their uptake, but the authors show that recent advances have made smaller-scale systems more viable through a greater understanding of optimising bacterial metabolism and productivity. Broader issues such as life cycle assessment and energy policies to promote AD are also discussed.
