Research Development of the Acid Fermentation by Activated Sludge

Anaerobic biological treatment of organic compounds generally went through three stages: hydrolysis stage,acidogenic and methanogenic stages of fermentation stage;Studies had shown that different fermentation types of acid formation played an important role in the whole anaerobic process,in addition,a large number of volatile fatty acids(VFAs) were produced during the anaerobic digestion process,such as acetic acid,propionic acid,butyric acid,etc.,could be used as chemical raw material for fermentation production of high value-added industrial products.the activated sludge acid fermentation type,the ecology of the acid producing bacteria,the impact factors of acid production process and the determination of VFAs were discussed in this article.