Comparative Study on the Performances and Bacterial Diversity from Anaerobic Digestion and Aerobic Composting in Treating Solid Organic Wastes

The differences of the physical and chemical parameters in the samples from the processes of anaerobic digestion (AD), aerobic composting (AC) and the residue after anaerobic digestion for aerobic composting (RAC) were comparatively investigated in this study. At the same time the quantities and structural characteristics of bacteria were studied by PCR-DGGE. The results showed that in the three ways for treating solid organic wastes, AC process had the most intensive decomposition of organic matter, with degradation rate of 51.51 %. The significant differences in temperature, pH and ammonia nitrogen (NH4+-N) content were observed in these treatments. The microbial species of Bacillus mainly existed in the process of AD while the Proteobacteria and Firmicutes primarily occurred in AC and RAC. AC has the most abundant biodiversity while the biological diversity of RAC is relatively single.