Investigation of the aerobic biochemical treatment of food waste: A case study in Zhejiang and Jiangsu provinces in China.

Food waste production is increasing rapidly and becoming a global concern. In areas with small production volumes and scattered production sources, the use of biochemical processors can be a beneficial supplement to the centralized treatment method for the in-situ treatment of wastes to effectively improve the efficiency of resource utilization. China is an important case study for this global issue; however, the implementation and outcomes of this process are not clear in China. In this study, field investigation and laboratory analysis were carried out on 14 biochemical processors in four representative regions of the Jiangsu and Zhejiang Provinces. The results showed that biochemical processors mostly used high-temperature aerobic fermentation, accounting for more than 80% of the commonly used procedures. The fermentation period was relatively short and ranged from 48 h to 10 days. Only 21.4% of devices were equipped with relatively complete secondary pollution-control units, which introduced the risk of secondary pollution during operation. The fermentation products exhibited common characteristics of acidity, high salt levels, and low maturity, rendering them unsuitable for agricultural use directly prior to an additional secondary fermentation process. Therefore, it is necessary to unify the design standards of biochemical processors and develop acid-resistant thermophilic microbial inoculants to increase fermentation efficiency. Thus, this study has significant implications in regulating food waste and serves as a theoretical and practical reference point to promote its in-situ treatment.