ANAEROBIC BIOCONVERSION OF MUNICIPAL SOLID-WASTES - EFFECTS OF TOTAL SOLIDS LEVELS ON MICROBIAL NUMBERS AND HYDROLYTIC ENZYME-ACTIVITIES

The anaerobic bioconversion of municipal solid wastes (MSW) produces b oth a valuable fuel product (methane) and a residue useful as a soil a mendment. The application of high-solids fermentation technology offer s improved economics over the more traditioinal low-solids fermentatio n systems. An important benefit of the high-solids process is the redu ction in process water, which results in smaller fermentation reactors , and thus lower capital and operating costs. However, the anaerobic b ioconversion process appears to be more efficient at high-solids as co mpared to low-solids levels. To understand the effects of solids level s on the anaerobic bioconversion process more thoroughly, representati ve high-solilds and low-solids anaerobic reactor systems processing id entical MSW feedstocks are compared with respect to fermentation perfo rmance, total microbial cell number, and important hydrolytic enzyme a ctivities.