Review of Acids Production by Anaerobic Fermentation of Organic Waste
The rapid development of intensive animal husbandry has contributed to an increasing a-mount of organic waste from livestock and poultry.The traditional anaerobic fermentation process for pro-ducing methane is challenging to integrate into a circular economy and carries the risk of contributing to the greenhouse effect.Research on anaerobic fermentation technology for the production of acid from or-ganic waste from livestock and poultry is of great significance for achieving a circular economy in animal husbandry.This article briefly introduces the mechanism of short-chain fatty acid production during anae-robic fermentation and the factors that affect the yield of short-chain fatty acids,and summarizes the prin-ciples and methods for increasing the yield of short-chain fatty acids,namely,the principle is to enhance the hydrolysis stage and inhibit the methane production stage,promote the rapid production of short-chain fatty acids,and reduce the consumption of short-chain fatty acids.Pretreatment of fermentation substrates and use of additives are common methods for increasing the yield of short-chain fatty acids in current re-search.Heat treatment,ultrasonic treatment,freeze-thawing,acid-base treatment,enzyme treatment,etc.can all increase the yield of short-chain fatty acids.Sodium 2-bromoethanesulfonate,biochar,and some broad-spectrum antibiotics are also used to increase the yield of short-chain fatty acids.This article will provide a reference to or point out new research directions for colleagues engaged in this field in the future.