The functional membrane is conducive to improve green waste composting process related microenvironment

Aerobic composting is an environmentally sustainable approach for the bioconversion of green waste (GW). However, conventional GW composting is often limited by prolonged processing times, low degradation efficiency, substantial nitrogen loss, and suboptimal product quality. In this study, three types of functional membranes (T1-T3) with varying air and moisture permeability were applied to assess their effects on the composting microenvironment, using an uncovered treatment (CK) as a control. Among all treatments, T2 demonstrated the most favorable outcomes, with a maximum composting temperature of 66.4 °C and an extended thermophilic phase lasting 12 days. Compared with CK, T2 significantly improved multiple parameters: moisture content, nitrate nitrogen, ammonium nitrogen, total nitrogen, organic matter degradation rate, fulvic acid, humic acid, and germination index increased by 29.3%, 36.3%, 63.0%, 15.9%, 22.8%, 8.3%, 11.1%, and 20.8%, respectively. Enzyme activities related to organic transformation, such as dehydrogenase, were also significantly enhanced. Notably, the composting maturity time for T2 was reduced to 26 days. A comprehensive evaluation using a membership function model revealed that the compost product index (CEI) of T2 reached 0.88, significantly outperforming other treatments. Furthermore, economic analysis indicated an 18.6% reduction in composting cost compared with CK. These findings suggest that an optimal membrane configuration can create a favorable composting microenvironment by regulating gas-liquid exchange, thereby enhancing nitrogen retention, accelerating organic matter transformation, improving compost quality, and reducing economic input. This study offers novel insights into the design of membrane-assisted composting systems for efficient GW management.