Rapid in-situ composting of household food waste

Composting can be used to reduce the volume of perishable food waste and increase soil fertility. In this study, an innovative composting device was developed to rapidly crush food waste at home. A special thermophilic microbial agent (Consists of four different functioning microorganisms) was prepared from the local food waste and rotted wood to facilitate degradation. After composting for four days with our device and microbial agent, the water-soluble organic carbon to total organic nitrogen ratio (WSOC/TON) in the mature compost was less than 0.55, the germination index (GI) reached 89.7 %, the pH value was 5.57 and the electrical conductivity (EC) was 1984 mu S cm(-1). The mature compost met the soil quality standards and was qualified as planting soil. This techno-economic evaluation shows that our domestic composting model saves labor, transport and classification costs compared with the centralized composting system, and presents new disposal and management model of domestic waste. The total cost of our device was only $0.033 per kg for food waste. Taking the disposal fee saved into account, the net profit of the mature compost was $89.06 per year. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.