Onsite treatment of urban organic waste using home composting systems.

摘要

On-site treatment (home and community composting) of organic waste (OW) reduces cost and environmental issues as opposed to centralized facilities and landfilling. By 2025, such on-site practices could reduce costs and greenhouse gas emissions (GGE) by 50 and 40 %, respectively, and save land as compared to maintaining landfilling practices. However, the shift of municipal solid waste (MSW) management systems from landfill disposal to resource recovery requires technological input, population participation and compost quality assurance. The composting process and quality of composted product depends on the initial compost mixture formulation, design type and management practices of home composting systems (HC).;A project was therefore conducted both in the laboratory and in the field, to establish a home composter design and compost formula, which favours the best organic waste decomposition.;The results indicated that home composter design is important: perforations must be concentrated at the top and bottom to provide an aeration level equivalent to that of a ground pile. Such home composters can reach thermophilic temperatures when fed at least 10 kg (week)-1 of organic waste with a dry matter content over 15 % (half yard trimmings and half food waste). The compost produced generally offers acceptable levels of polycyclic aromatic hydrocarbons (PAHs) and heavy metals, but residents must be careful in applying the right amount of garden herbicides. The total GGE from home composters were found to be equivalent to that of centralized composting facilities but eliminate the need to spend energy equivalent to 50 kg CO2-eq (tonne wet waste)-1 for handling and processing.