Animal Husbandry
        Animal husbandry industry is an important part of China's agriculture and rural economy. The problem of environment pollution caused by the rapid development of animal husbandry industry is increasingly serious. Emissions of major pollutants from agriculture, life and industry sources were analyzed and summarized in the First National Survey Bulletin of Pollution Sources, which was released in February 2010. Among the agriculture sources, the COD and ammonia nitrogen emissions in animal husbandry industry were 1,268,26,00 tons and 717,300 tons respectively, accounting for 95.8% and 78.1% of the agricultural COD and ammonia nitrogen emissions, and 41.9% and 41.5% of the national COD and ammonia nitrogen emissions.
Solution: anaerobic and natural treatment technology
       Anaerobic treatment is characterized by low cost, small footprint, low energy demand. It also produces biogas. Moreover, the treatment process does not require oxygen, and it is not limited by the ability to transmit oxygen. Therefore, it has a high organic load potential, which can degrade organic matter in parts that aerobic microorganisms cannot degrade. The common anaerobic methods include fully mixed anaerobic digester, anaerobic contact reactor, anaerobic baffled reactor, up flow anaerobic sludge bed, anaerobic fluidized bed, and up flow solid reactor, etc. The natural treatment is to use the combined action of natural water, physics, chemistry and biology to purify waste water. This kind of method is economical in investment, simple in process, requiring less power consumption. But its purification function is restricted by natural conditions. The main modes of natural treatment are oxidation pond, soil treatment and artificial wetland treatment.