Home Composting for Onsite Treatment of Household Organic Solid Waste: A Review

Purpose of Review Home composting is an effective way to treat household waste, but global uptake remains low because of insufficient recognition and technical limits. This review aims to promote the understanding, popularization, and application of home composting by summarizing the facilities, process performance, and product quality, and to sum up the crucial technical limits and potential solve methods. Recent Findings Home composting studies are carried out in 20-1200 L composters for 3-12 months with kitchen and garden feedstocks. During the process, emission amounts of methane (CH4), nitrous oxide (N2O), and ammonia (NH3) are 0.002-2185 kg/Mg FW, 0.004-454 kg/Mg FW, and 0.025-972 kg/Mg FW, respectively. The thermophilic stage in home composting is insufficient for harmless requirement, while the home composting products could meet the standards for the use of organic fertilizer when the basic physical and chemical indicators, biological indicators, spectral indicators, and other indices are carried out in lab. Home composting products are non-toxic to plants and can promote plant growth. The crucial technical limits are caused by slow degradation of organic matter (OM), emission of greenhouse gases (GHGs) and a lack of maturity evaluation standard and directive for subsequent product utilization. Suitable technology and evaluation standard could reduce gas emissions and improve maturity of home composting, which would provide an additional method for existing municipal waste management, therefore reducing the transportation and collection cost of household waste, and realizing the reduction, harmless, and resource recovery.