Anaerobic Digestion: Principles and Practices for Biogas Systems

摘要

The report is part of a joint global research, development and demonstration effort of the United Nations Development Programme and the World Bank. It explores the history, technology, and applications of anaerobic digestion, the biological process by which organic materials are degraded in the absence of oxygen to produce a combustible gas, methane (CH4), and carbon dioxide (CO2). The process occurs naturally in wet, decaying organic matter (biomass) found in swamps, bottom muds of streams, and garbage dumps. Since about 1900, it has been used in engineered systems for treatment and stabilization of municipal or industrial sludges. Starting around 1920, systems have been operated so as to capture the biogas, identical to marsh gas which contains about 55-75 percent methane, as an energy source. In addition to producing a fuel substitute, benefits of digestion include reduction or elimination of pathogens in human and animal wastes and production of a stable, generally environmentally acceptable slurry or sludge which can be used as a fertilizer and soil conditioner. (Copyright (c) 1986, The International Bank for Reconstruction).