Effect of ventilation rate on co-composting of night soil and leaf

Aerobic static co-composting of night soil and leaf under different ventilation rates of 0.08, 0.14 and 0.2 m3/(min·m3) was studied in pilot scale for obtaining the best ventilation rate. The indexes such as temperature, CO2 concentration, germination index, fertilizer efficiency such as nitrogen, phosphorus and potassium and contents of heavy metals were analyzed to examine the feasibility of co-composting of night soil and leaf. Results show that: when the wet basis ratio of night soil and leaf was 3/1, night soil and green waste (leaf) can realize co-composting under different ventilation rates of 0.08, 0.14 and 0.20 m3/(min·m3). And the optimal ventilation rate was 0.14 m3/(min·m3) . The fertilizer efficiency and content of heavy metals of co-composting products accord with the national standard.