Wp?yw wst?pnej obróbki osadu ?ciekowego na efektywno?? procesu fermentacji metanowej

摘要

The aim of this paper is to demonstrate the effects of pre-treatment increase of the efficiency of anaerobic digestion on waste activated sludge. There were four methods for pre-treatment of the waste activated sludge: A – thermally treated at 121°C for 30 min, homogenized and hydrolysed by Bacillus subtilis bacteria, B – thermally treated at 121°C for 30 min and homogenized, C – thermally treated at 121°C for 30 min and hydrolysed by B. subtilis bacteria, D – thermally treated at 121°C for 30 min. The process consisted of a hydrolyses phase and anaerobic digestion phase operated at 36°C ±1°C for 35 days. It was investigated with regard to hydrolytic enzymes: amylase, cellulase, lipase and protease. Acetic acid (4.3 g?dm-3) and butanediotic acid (0.1 g?dm-3) were reported to appear in biggest quantities in volatile fatty acids according to measurement of VFA. The amount of carbon and nitrogen decreased while the ratio of C:N increased from 8:1 to 10:1. The highest methane yield was obtained in A method.