Effect of powerless-ventilation on large-scale facultative composting: Maturity and pollutant gas emissions

Composting can convert livestock manure into organic fertilizers. However, composting with forced aeration does not allow for large - scale composting due to power consumption. Therefore, this study investigated different powerless – ventilation conditions to improve the performance of large - scale facultative composting. Under the powerless-ventilation with double-membrane-covered and addition of cornstalks treatment, the maturity of compost was most effective (GI reached 118 %). The conditions of powerless - ventilation with membrane covering and cornstalk addition can reduce CH₄ emissions by 84.47 % and H₂S emissions by 28.08 %. The doublemembrane- covered treatment was less effective in reducing gas emission compared with single-membrane-covered. Among the composting conditions, the powerlessventilation with membrane-covered and addition of cornstalks could achieve the best effect of promoting maturity and reducing emissions. The nutrient contents of total nitrogen, total phosphorus, and total potassium increased by 6.21 %, 18.14 %, and 13.22 % under the conditions of powerless-ventilation with membrane-covered and addition of cornstalks. Optimizing the large-scale composting process is an important means to reduce the emission of pollutant gases. This study can provide scientific basis for the large-scale treatment of agricultural waste • Powerless-ventilation can achieve low-cost utilization of large-scale manure. • Powerless-ventilation can promote the maturity by 15 % during composting. • Powerless-ventilation with Single-layer membrane is the most effective way. • Optimizing the process can improve the nutrient content of products by 37.57 %. • Gas emissions had the high correlation with temperature and germination index.