Effects of Wheat Straw and Ashing Temperature on the Ash Fusion Characteristics of Food Waste

Abstract

The disposal of food waste (FW) has brought severe challenges to the environment and society, the application of gasification technology provides new ideals for its resource utilization, and the effective slagging is one of the key points for this technology. This study mainly focuses on the ash fusion characteristics of FW under different temperature and wheat straw (WS) addition conditions, and analyses of XRF, XRD and SEM were performed to characterize the properties of the ashes. Results show that the ash fusion temperatures (AFTs) of FW were higher than that of WS, and both increased with the temperature due to the volatilization of alkali metals and the formation of high melting points substance such as quartz and mullite. The AFTs of FW decrease by about 23 °C with the blending of 10% WS at 800 °C, and it decreases non-linearly with increasing WS ratio, which mainly originated from the interaction between the ashes of FW and WS. Although the increase of mullite content makes the AFTs of WS50 higher than the calculated value, the increase of low melting point substances such as anorthite and the existence of leucite in WS50 resulting in its lower AFTs than that of FW.