Application of a Maturity-accelerating Reagent (MAR) to Food Wastes Composting Processes

Y. Li, J. Liu, G. Huang, H. Yu, K. An and B. Zhang

Abstract
In order to increase the degradation rate of organic materials and reduce ammonia emissions simultaneously during the aerobic composting period, a commercial maturity-accelerating reagent (MAR) was employed. Comparative composting experiments were conducted: Run A with the addition of MAR in the composting mixture, and Run B without the addition of MAR, while some parameters such as organic carbon, ammonia, and pH were measured under controlled air flow rate in the composting process. After 26 days of composting, the experimental results revealed that the degradation rate in Run A (21 g kg–1 d–1 DM (dry mass)) was higher than that in Run B (18 g kg–1 d–1 DM) by 16.7 %, while ammoniacal N (NH3 and NH4+) retained in Run A was 13.6 g kg–1 DM, which was more than that in Run B (8.3 g kg–1 DM), possibly because struvite crystal was formed. Apparently, the application of MAR had a positive effect on composting wastes, not only promoting organic degradation and nitrogen conversion, but also improving the quality of the compost, to be used as soil amendment in agriculture.

This work is licensed under a Creative Commons Attribution 4.0 International License

Keywords
Ammonia emissions, degradation rate, struvite crystal, ammoniacal nitrogen, oxygen uptake rate