After last 30 years of development, the current anaerobic treatment technology for industrial wastewater and livestock wastes has been in large and medium scale in China. By the end of 2000, 400-500 different kinds of biogas projects for industrial wastewater treatment and over 600 large and medium biogas projects for livestock wastewater and residue treatment had been set up in China. It is estimated that the biogas yield is about 1 billion M~3/a, equivalent to 1 million tons of standard coal. The anaerobic fermentation technology has been applied in wastewater treatment project of nearly 20 industries, such as alcohol, fermentation, slaughter, pharmacy, livestock, chemical etc.. The technologies mainly applied in the project are complete stirred anaerobic process and UASB process. The reactors of the above technologies and their components have been initially completed in serial design. The new process and technology imported from foreign countries are double-folded side biting technology and assemble tank -making technology. After digestion and absorption, these technologies have been widely used in China. There are different types of complete equipment of anaerobic technology (such as solid-liquid separator, biogas storage tank, anaerobic sludge dewatering, biogas desulphurization burning equipment and generator) which are manufactured and sold in the market. Most of the biogas generated from the anaerobic fermentation are used as industrial boiler fuel and for civil purpose and electric energy generation. The digestive liquor after anaerobic fermentation has been handled by different aerobic treatments and agricultural irrigation technology, so as to meet the national discharge standard. It is expected that by 2005, large and medium biogas projects will increase to 2000, with treatment capacity for organic wastewater of 200 million M~3/a, and a biogas yield of 2 billion M~3/a has been formed (equivalent to 2 million tons of standard coal), which can generate electricity of 3.333 billion KWH/a.
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