Since the 1950% China has experimented with the production of biogas from agricultural wastes, a practice based upon an age old Chinese tradition of composting human, animal and plant wastes to produce an organic fertilizer of high quality. The breakthrough came in 1975 when a process was developed to ferment the materials in an airtight and watertight container in order to produce methane gas. This was then collected for use as fuel for motors, cooking and lighting.
The production of biogas, which is regarded in many countries as a by-product of an efficient system of energy production, has become in China a comprehensive, controlled
method of waste disposal, recycling resources, supplying energy and fertilizer and improving rural health, asthe digesting of wastes in a closed container kills many of the pathogens responsible for common human diseases.A Chinese Biogas Manual
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