Coal Coke Gasification in a Windowed Solar Chemical Reactor for Beam-Down Optics

Solar thermochemical processes, such as solar gasification of coal, require the development of a high temperature solar reactor operating at temperatures above $1000°C$⁠. Direct solar energy absorption by reacting coal particles provides efficient heat transfer directly to the reaction site. In this work, a windowed reactor prototype designed for the beam-down optics was constructed at a laboratory scale and demonstrated for $CO2$ gasification of coal coke using concentrated visible light from a sun-simulator as the source of energy. Peak conversion of light energy to chemical fuel (CO) of 14% was obtained by irradiating a fluidized bed of $500–710μm$ coal coke size fraction with a power input of about 1 kW and a $CO2$ flow-rate of $6.5dm3min−1$ at normal conditions.