Techno-economic analysis of chemical looping processes with biomass resources for energy production and CO2 utilization. Comparison of CLC and CLOU technologies

Abstract

Bioenergy coupled with carbon capture utilization and storage (BECCUS) is an attractive greenhouse gas mitigation technology that can produce negative CO2 emissions by combining bioenergy resources with the utilization or geological storage of the captured CO2.The main objective of this work was to evaluate the technical and economic feasibility of two BECCUS technologies based on chemical looping concept with two biomass waste as fuels, i.e., swine manure and pine sawdust, for the production of thermal energy and a pure CO2 stream that is subsequently used as raw material in agricultural greenhouses. Direct use of solid biomass resources was considered for the Chemical Looping with Oxygen Uncoupling option, whereas biogas production was the starting point for Chemical Looping Combustion.The profitability of the chemical looping scenarios was assessed through the Levelized Cost of CO2. This parameter was estimated at 218.31 €/t CO2 for the Chemical Looping Combustion scenario, a value much higher than those for the Chemical Looping with Oxygen Uncoupling scenarios (73.04–87.32 €/t CO2) due to the limited conversion degree of the carbon present in the fuel waste to biogas and the need for an additional experimental plant to the Chemical Looping Combustion unit, i.e., the biogas production plant. Comparing the Chemical Looping with Oxygen Uncoupling scenarios, the economic analysis revealed that the profitability of the biomass-fueled chemical looping facility was markedly sensitive to the selling price of the biomass resource. Furthermore, the values of the Levelized Cost of CO2 parameter for the Chemical Looping with Oxygen Uncoupling scenarios were lower than those estimated in other research studies that implemented BECCUS technologies and utilized the captured CO2 for identical purposes. In the particular case of swine manure, this result becomes even more noteworthy since it demonstrates that the energy use of this biomass resource through Chemical Looping with Oxygen Uncoupling technology is an economically profitable and environmentally sustainable solution to the difficult challenge of managing this livestock waste. Therefore, it can be concluded that Chemical Looping with Oxygen Uncoupling processes fed with biomass are a very attractive BECCUS technology for heat generation where, in addition, the pure CO2 stream obtained at the outlet of the fuel reactor can be considered a marketable, high value-added product.