Current issues of eliminating odor pollution of the environment by poultry by-products: a review
N.V. Syrchina, T.Ya. Ashikhmina, M.H. Kheto
Section: Theoretical problems of ecology
The operation of modern poultry farms is accompanied by the formation of a significant amount of by-products, chicken manure (CM) is among them. The accumulation of manure near poultry farms causes odor pollution of residential areas. Odor-forming substances (OFS) are formed during the metabolism of undigested feed residues a variety of microorganisms that enter the manure from the intestines of chickens and the external environment. Short-chain fatty acids, volatile sulfur compounds (H2S, thioalcohols, thioethers, etc.) and nitrogen (NH3, biogenic amines, etc.) make the main contribution to odor formation. Such bacteria as Firmicutes, Proteobacteria, Bacteroidetes, Actinobacteria, as well as fungi Mucor, Aspergillus, Penicillium, Fusarium dominate in fresh CM. The microbiota composition changes significantly during storage or composting. In particular, the number of Firmicutes decreases and the number of Actinobacteria increases. The microbial community transformation is accompanied by a change in odor. Fresh CM have the most intense odor. Active research is underway to develop methods to deodorize CM. Methods involving the use of microbiological preparations, acidity regulators, and natural sorbents are of greater practical interest. Materials used as deodorants inhibit OFS-producing putrefactive microbiota or eliminate odor by destroying, immobilizing, and masking of OFS. Chemical and physical-chemical methods of deodorization are more convenient for industrial processing of CM into commercial forms of fertilizers. The combined effect of lime (a chemical reagent) and glauconite (a sorbent) followed by drying the mixture leads to a significant reduction of CM odor. The disadvantages of this method include significant losses of nitrogen (in the form of NH3) during the decomposition of ammonium salts in an alkaline medium. To prevent the NH3 emission into the atmosphere, it is possible to use the technology of absorption of this gas by an acid solution (for example, sulfuric acid). The ammonium sulfate formed in this way can be used as a nitrogen fertilizer.
ISSN 1995-4301
Select viewing options
