BIOGAS PRODUCTION FROM SEWAGE SLUDGE BY ANAEROBIC DIGESTION

Abstract

In this research was studied the possibility of producing biogas from sewage sludge by anaerobic digestion and assess the efficiency of the anaerobic treatment of sludge through the measurement of a number of physical and chemical properties of the sludge before and after treatment and calculate the respective removal rates. Primary sewage sludge was used for biogas production at 35o C, and a retention time of 30 days; has been shown that possibility of producing biogas from primary sludge, with daily production rate average of 52.27 cm3 biogas.day-1, and the average yield production was 47.41 cm3 biogas per g volatile solids added. And that the results of the gas chromatography analysis, show the presence of a low percentage of methane within the contents of biogas amounted to 37.11%, in addition to low removal rates recorded 16.34% for total solids, and 26.96% for the volatile solids; 28.05% for COD; 32.48% for BOD, and higher proportion of organic carbon amounted to 42.13%, with a very low removal rate for total nitrogen 3.4%, and 8.7% for phosphorus, as well as remove most of Coliform bacteria with removing rate 94.68%. Recording with a rise in pH to 7.9 at the end of the digestion.