Gasification of effluent from food waste treatment process in sub- and supercritical water: H2-rich syngas production and pollutants management

Mi Yan; Hongcai Su; Zhihao Zhou; Dwi Hantoko; Jianyong Liu; Jingyi Wang; Runpei Wang; Ekkachai Kanchanatip

doi:10.1016/j.scitotenv.2020.138517

Gasification of effluent from food waste treatment process in sub- and supercritical water: H₂-rich syngas production and pollutants management

Sci Total Environ. 2020 Aug 15:730:138517. doi: 10.1016/j.scitotenv.2020.138517. Epub 2020 Apr 23.

Authors

Mi Yan¹, Hongcai Su¹, Zhihao Zhou¹, Dwi Hantoko¹, Jianyong Liu¹, Jingyi Wang², Runpei Wang³, Ekkachai Kanchanatip⁴

Affiliations

¹ Institute of Energy and Power Engineering, Zhejiang University of Technology, Hangzhou 310014, China.
² Zhejiang Zheneng Xingyuan Energy Saving Technology Co., Ltd, Hangzhou 310013, China.
³ Hangzhou Environmental Group, Hangzhou Environment Group Co., Ltd, Hangzhou 310000, China.
⁴ Institute of Energy and Power Engineering, Zhejiang University of Technology, Hangzhou 310014, China; Center of Excellence in Environmental Catalysis and Adsorption, Faculty Engineering, Thammasat University, Pathumthani 12120, Thailand. Electronic address: k_ekk@hotmail.com.

PMID: 32402957
DOI: 10.1016/j.scitotenv.2020.138517

Abstract

The effluent of food waste (FWE) is generated during food waste treatment process. It contains high organic matter content and is difficult to be efficiently treated. In this study, the sample was collected from a 200 t/d food waste treatment center in Hangzhou, China. Subcritical and supercritical water gasification were employed to decompose and convert FWE into energy. The effects of reaction temperature (300-500 °C), residence time (20-70 min) and activated carbon loading (0.5-3.5 wt%) on syngas production and the remaining pollutants in liquid residue were investigated. It was found that higher reaction temperature and longer residence time favored gasification and pollutant decomposition, resulting in higher H₂ production and gasification efficiencies. It is noteworthy that the NH₃-N was difficult to be converted and removed under current experimental conditions. The addition of activated carbon was found to increase the gasification efficiency. The highest total gas yield, H₂ yield, carbon conversion efficiency, gasification efficiency, total organic carbon removal efficiency and chemical oxygen demand removal efficiency were obtained from gasification at 500 °C for 70 min with 3.5 wt% activated carbon.

Keywords: Effluent; Food waste; Gasification; Hydrogen; Sub- and supercritical water.