Decentralized composting of household wet biodegradable waste in plastic drums: Effect of waste turning, microbial inoculum and bulking agent on product quality

Household wet biodegradable waste (HWBW) forms a major portion of municipal solid waste (MSW) in developing nations. Its recycling at the source of generation can not only reduce waste transportation costs but also prevent harmful air emissions. Therefore, the present study was planned to investigate the performance of a decentralized household composting system for onsite recycling of source-segregated HWBW. The study was carried out in the recycled plastic drums (capacity = 100 L). The effect of waste turning and addition of microbial inoculum and bulking agent (garden waste) on the composting process was examined. The results showed that proper provisions for aeration and periodic waste turning are necessary to produce good quality compost. The addition of a suitable microbial inoculum can reduce duration of waste stabilization. During composting, the peak temperature was found greater than 55 degrees C for 3-6 days and the compost yield (<4 mm fraction) was 18%-20%. The phytotoxicity tests results showed that the growth of cress plants is not affected in the presence of 20% of compost mixed in soil. One-time addition of inoculum at the start of composting process was found sufficient for completion of the active decomposition period within 30 days. Based on the above results, two-drum systems can be suggested as feasible option to produce compost from HWBW. (C) 2019 Elsevier Ltd. All rights reserved.