Household organic waste composting using bins with different types of passive aeration

The objective of this study was to study the performances of six 200-L polyethylene bins, each with different design for passive aeration to organic wastes composting. Food scraps and dry leaves (1.6 kg) were added to each bin once a day until the bin was full. Temperatures at the middle portion were measured daily. The compost from each bin was taken once a week for 120 days for analysis of C, N, volatile solids, and a germination index once a week for 120 days. After 120 days, the compost sample from each bin was taken to determine the mass reduction, size distribution, CEC, N, P and K values. The results showed that the temperatures inside the bins were in the ranges of 24 °C–57 °C. The composts in all bins were found to be stable at around 56–91 days. The wastes decayed fastest in bins with lateral and vertical systems of natural ventilation. It took about two months to stabilize the organic wastes, with a 59–62% decrease of mass. The C/N ratio, CEC, N, P, and K values of the final composts were 14.8–16.0, 66–68 cmol/kg, and 1.26–1.50% N, 0.52–0.56% P2O5 and 1.66–1.92% K2O, respectively.