Potential for Anaerobic Digestion (AD) Technology to Treat Organic Solid Waste at Community Level: A Case Study in Gongo La Mboto, Dar Es Salaam Tanzania

Abstract

This paper looks at the potential of anaerobic digestion technology to treat Organic Fraction of Municipal Solid Wastes (OFMSW) in Gongo la Mboto in Dar es Salaam city.   The study evaluates municipal solid waste generation, and composition, at transfer station level. Composition analysis of waste determined the relative amount of (OFMSW).  For composition analysis of waste standard method ASTM-D5231-92 was used. 100 kg of sample was subjected to reduction of the sample using quartering technique. Then the reduced sample was sorted out manually into following categories: food waste, plastics, paper, tin cans, and metals, rubber and glass. Subsequently, the weight of each component were measured and recorded. Other parameters which were evaluated are moisture content of organic fraction, and volume of the digester. The results show that on average 34.39tons/day ton of solid waste is generated/day giving a per capita generation rate of 0.6kg/capita/day based on population of 57312. Results of  waste composition analysis was as follows: food waste accounts for 39%, metals13.6%, wood 10.4%, plastics 9.4%, tin cans 8.4%, paper 7.8%, rubber 6.2% and glass 5%. Analysis indicated 78.3% moisture content of OFMSW. Amount of OFMSW generated was 13.41tons/day. Anaerobic digester of 761 m³ volume was estimated. The study findings indicates that since OFMSW is high, anaerobic digestion could be an appealing option for converting raw solid organic wastes into biogas, which may play a critical role in meeting the world’s ever-increasing energy requirements in the future.