Biodegradabilities and Microbial Activities During Composting of Municipal Solid Waste In Bench-Scale Reactors

In the design of large scale, in-vessel systems, the biodegradability of the waste, the optimal nutritional conditions, and the length of time required to complete the high-rate phase are important. Because composting is a microbial process, the overall levels and activities of microorganisms influence the rate and extent of degradation. In this study, bench-scale reactors were used to determine the biodegradability of municipal solid waste, primarily office trash, and the effects of nutrient supplementation on biodegradability during six weeks of composting. Supplementation with nitrogen, phosphorus, vitamins, and trace minerals did not increase the biodegradability of the waste. Although the levels of specific microbial subpopulations varied, total numbers of microorganisms did not change significantly.