Solar-driven gasification of carbonaceous feedstock—a review

Abstract

Given the future importance of solid carbonaceous feedstocks such as coal, coke, biomass, bitumen, and carbon-containing wastes for the power and chemical industries, gasification technologies for their thermochemical conversion into fluid fuels are developing rapidly. Solar-driven gasification, in which concentrated solar radiation is supplied as the energy source of high-temperature process heat to the endothermic reactions, offers an attractive alternative to conventional autothermal processes. It has the potential to produce high-quality synthesis gas with higher output per unit of feedstock and lower specific CO₂ emissions, as the calorific value of the feedstock is upgraded through the solar energy input by an amount equal to the enthalpy change of the reaction. The elimination of an air separation unit further facilitates economic competitiveness. Ultimately, solar-driven gasification is an efficient means of storing intermittent solar energy in a transportable and dispatchable chemical form. This review article develops some of the underlying science, examines the thermodynamics and kinetics of the pertinent reactions, and describes the latest advances in solar thermochemical reactor technology.