Comparative evaluation of aeration methods for municipal solid waste composting from the perspective of resource management: A practical case study in Tehran, Iran

摘要

During four months of practical composting examination, common aeration techniques including forced aeration static pile, pile turning, natural ventilation static pile and a combination of pile turning and natural ventilation static pile were investigated to determine the most appropriate method for a full-scale composting procedure using the organic fraction of Tehran's municipal solid wastes. The results of measured parameters such as temperature, pH, electrical conductivity (EC), C/N, and main nutrients including nitrogen, phosphorus and potassium suggested that both forced aeration and pile turning have efficacy in terms of final compost quality although pile turning showed better results for agricultural applications nevertheless significant energy consumption and pollutant emissions were associated with them. The combination of pile turning and natural ventilation could solve the problem of long degradation time and concurrently guarantee the acceptable quality of finished compost for agricultural purposes. Furthermore, this combinative method showed a specific energy consumption as low as 0.218 MJ per kg-dry and had a potential to save 288.8 kg-CO2/ha by applying the achieved compost on the farm in order to replace the chemical fertilizers.