Analysis of biomass as a feedstock in a chemical looping-based polygeneration process for CO2 valorization

Abstract

From the viewpoint of circular economy, the utilization of biomass as a preferred feedstock for power generation with carbon capture has become prevalent. Biomass utilization leads to a carbon-neutral balance by leveraging its inherent carbon that was absorbed from the atmosphere. While chemical looping combustion (CLC) is a promising carbon capture technology for solid fuels such as coal, this paper further explores the feasibility of using biomass in CLC along with valorization of CO₂ to valuable chemicals. A polygeneration approach utilizing biomass has been proposed to produce power and value-added chemicals (methanol and dimethyl ether [DME]), thus yielding an integrated CO₂ capture and utilization system. Biomass has a significant amount of oxygen and a higher H:C ratio than conventional fuels like coal. The effect of the same has been analyzed by assessing biomass as a feedstock in the proposed process and evaluating the effect of higher oxygen content towards the objective of CO₂ valorization relative to that of coal. Furthermore, a comparative discussion of the suitability of biomass compared to coal from a valorization perspective has been presented. Detailed techno-feasibility analysis on the schemes and optimization studies to maximize the performance of the system in terms of energetics, CO₂ mitigation, and profitability has been conducted. From the analysis, it has been identified that the utilization of biomass as a feedstock in CLC-based processes results in higher chemical production rates and higher profits with lesser CO₂ emissions than coal. The above analysis and evaluation has been carried out through simulations using Aspen Plus® software.