Studies on Dynamic Change of Humic Acid in Chicken Manure Composting

摘要

Composting technology is used to treat chicken manure in this study,and the dynamic change of the thermal,optical properties and the elemental composition of humic acid (HA) are systemically studied in the process of composting.Results showed that the medium exothermic peak temperature and the high exothermic peak temperature of HA are gradually increased with the prolonging of composting time,and weight loss also increased significantly at high exothermic peak.Infrared spectral analysis indicated that,HA molecules such as polysaccharides,lipids and other small molecule compounds decreased,while the aromatic compounds increased.The change of hue coefficient (△1gK) showed that HA molecular weight is relatively small even in the late composting and there is further stabilized potential.The H/C of HA molecules decreasing tendency further confirms that composting is conducive to higher degree of condensation of HA and further complicated molecular structure,which can promote the HA maturation.