Urban energy mining from municipal solid waste (MSW) via the enhanced thermo-chemical process by carbon dioxide (CO2) as a reaction medium

Abstract

The enhanced gasification of municipal solid waste (MSW) using carbon dioxide (CO2) as the gasification medium was investigated to achieve environmentally benign and energy efficient ways for the disposal of MSW. Two main steps of thermal decomposition of MSW were observed. The first thermal degradation step occurs at temperature between 280 and 350 degrees C and consists of the decomposition of the biomass component into light C1-3-hydrocarbons. The second thermal degradation step occurs between 380 and 450 degrees C and is mainly attributed to polymer components, such as plastics and rubber, in MSW. To extend this understanding to a more practical level, MSW samples were tested in a drop tube reactor (DTR) at a temperature range from 500 to 1000 degrees C under various atmospheres with CO2 concentrations of 0-30%. The release of major chemical species from the DTR has been determined using a micro-GC. For example, CO (similar to 30%), H-2 (similar to 25%) and CH4 (similar to 10%) were generated.