Transformation of Biodegradable Organic Municipal Solid Waste to Compost Using Stationary and Rotary Units

Abstract

This study aims to convert the municipal solid waste (MSW), which include garbage and chicken manure as raw biodegradable organic waste to produce a compost in order to transform these materials into recommended fertilizer. The principle of aerobic composting method is a waste oxidation through holding these mixed raw materials with a ratio of 1:1 garbage and chicken manure in two units of composting, rotary unit and stationary unit with recommended Carbon/Nitrogen ratio C/N of 20:1 and pH of 6.5 with moisture content of about 40% by adding water during composting process and presence of oxygen naturally. The period time of composting process was 69 days to get normal temperature of compost bulk equal to ambient temperature and pH value as natural value using two composting units. The composting results during first 30 days shows the temperature values 59.5 and 55oC for rotary unit and stationary units that refers to microbial action of microorganism and decomposition of organic matter to energy as heat. The pH values were having acidic state during first week that refers to the formation of organic acids. The final compost characteristics show a C/N ratio of 20.8 and 22.275 for rotary and stationary units, respectively with a decrease in C% and N%, which refers to a successful composting process, where Nitrogen, Phosphor and Potassium NPK values were (1.428:1.719:4.508) % for rotary unit and (1.361:0.419:3.884) % for stationary unit and electrical conductivity of 5.5 and 6.04 mS/cm as acceptable value according to the recommended standard values.