Experimental study of anaerobic digestion of dog waste

Abstract

Bioconversion of dog waste (dung) to energy as one of the ways for proper disposal of the waste was carried out through anaerobic digestion for biogas production. The 59-day experiment was performed within the slurry temperature range of 28 and 44°C using a 50 L metallic biodigester. Prior to charging the digesters, physico-chemical properties and microbial content of the waste were determined using standard methods. The results show that a cumulative gas production of 200 L was generated by 7 kg of the waste at the end of the test period while the microbial load decreased from 8.2×10 14 at the beginning of the test to 4.2×10 8 at the end of the retention time. Five microorganisms were identified at the beginning of the charging period, four were identified at the 20 th day when the gas began to burn due to methane production while only one microorganism was identified at end of the test. Even though it has longer retention period than most common animal wastes used for biogas production, its gas production rate is low. However, pathogen reduction through anaerobic digestion justifies its conversion to energy by this method.