[Rapid and high-efficient composting process of municipal sewage sludge]

Based on the static composting process of the municipal sewage sludge (MSS), the paper demonstrates the dynamic composting process of the MSS from Shanghai Quyang Municipal Wastewater Treatment Plant. The dynamics of different operational and evaluating indices during the treatment process are discussed, such as water content, temperature, pH, dissolved organic carbon (DOC) and germination index (GI) and so on. It is concluded that the water content of materials, temperature,DOC and GI can be interpreted as the evaluating indices of the maturation of MSS. Under optimized condition, when the water content of initial materials was adjusted to 60 % +/- 2 % with appropriate sawdust and recycled materials, the results indicated that the temperature of composting materials could reach > 55 degrees C rapidly and last 4 days, thus 100% of the pathogens would be killed out. In the end of composting process, the water content of outputs was reduced exactly to about 35%, DOC could be decomposed by about 50%. T heincompact, odorless, and almost mature output could meet the land application control standard of MSS and the class A standard of US EPA.