Effect of Temperature on Dry Anaerobic Fermentation of Animal Manure and Straw

Abstract

Dry anaerobic fermentation of animal manure and straw was conducted to produce biogas. Under C/N=25-30 and TS=20%, three different temperature conditions of room temperature condition(16.5°C-25°C), mesophilic condition(36°C) and thermophilic condition(55°C) were tested to investigate the effect of operation temperature on dry fermentation. The results show that dry fermentation under room temperature starts up slowly with low biogas production, so room temperature is unfit for dry fermentation. Dry fermentation under thermophilic condition and mesophilic condition proceed steadily with high biogas production and mesophilic condition is more suitable for dry fermentation. The organic loading rates under thermophilic condition and mesophilic condition are 1.69 kg•m-3•d-1 and 1.89 kg•m-3•d-1 respectively with total solid (TS) biogas yields of 0.237 m3•kg-1 and 0.208 m3•kg-1, and volumetric biogas yields of 0.401 m3•m-3•d-1 and 0.393 m3•m-3•d-1 respectively. It could provide instructive meaning to the engineering application of dry anaerobic fermentation.