Studies on the biological stabilization of thin stillage. II. Anaerobic fermentation.

Abstract

Sedimented solids, obtained as a slurry after the aerobic fermentation of thin stillage, were subjected to anaerobic decomposition in stirred culture. The solids were added gradually in increasing increments to anaerobic sludge from a sewage disposal plant for purposes of acclimatization. The fermentation resulted in the generation of large volumes of gas with a methane content of 70% and a reduction in chemical oxygen demand of approximately 65%. Gas production was somewhat inferior to that obtained during anaerobic decomposition of "raw" thin stillage solids.