Long-term characterization and resource potential evaluation of the digestate from food waste anaerobic digestion plants
2021
Wang, Ning | Huang, Dandan | Zhang, Chao | Shao, Mingshuai | Chen, Qindong | Liu, Jianguo | Deng, Zhou | Xu, Qiyong
The management of digestate from food waste (DFW) has become a big challenge for anaerobic digestion (AD) plants. It is crucial to understand the characteristics of DFW for its beneficial utilization. This study investigated the long-term characteristics of DFW from an industrial-scale AD plant in China for 16 months. The result showed that the characteristics of the DFW were relatively stable. The DFW contained considerable amounts of organic matter (23–40% of lignin and 12–26% of protein) and abundant nutrients (N, P, and K), with high concentrations of metals (e.g., 55.17 mg g⁻¹ and 15.55 mg g⁻¹ of Ca and Fe) and sulfur (1.40%) on a dry basis. Based on the results, pyrolysis and composting were evaluated as optional conversion ways of DFW. The pyrolysis temperature range of 500 °C to 600 °C was recommended for producing biochar. In this temperature range, the Brunauer-Emmett-Teller surface area of the produced biochar is over 120 m² g⁻¹. The composting offered the best potential for recovering the nutrients from DFW, but the high ammonia gas content (6970 ppm) should be paid attention to during composting.
显示更多 [+] 显示较少 [-]