Application of calcium oxide/ferric oxide composite oxygen carrier for corn straw chemical looping gasification

Biomass chemical looping gasification (CLG) technology is an important utilization form of renewable energy. In order to obtain high-quality syngas, CaO/Fe2O3 was used as a composite oxygen carrier for biomass CLG in this study. The CLG experiment of corn straw and the study of oxygen carrier recycling were carried out, simultaneously, the reaction mechanism was further discussed. Results shown adding CaO to oxygen carrier could significantly improve the quality of syngas through increasing the H2 and reduce Greenhouse gas (CO2 and CH4, about 14% reduction). Besides, the ratio of Fe2O3 to CaO, steam to biomass, and oxygen carrier to biomass all affected the syngas composition (the H2/CO variation from 1.82 to 2.19), while the temperature had obvious influence on the gas yield of CLG. The most possible reaction mechanism shown that the variation of Ca might be the main factor of gas composition fluctuation.

Automated summary

The study used CaO/Fe2O3 as a composite oxygen carrier for biomass chemical looping gasification (CLG), showing that adding CaO can significantly improve the quality of syngas and reduce greenhouse gas emissions. Various factors such as the ratio of Fe2O3 to CaO, steam to biomass, and oxygen carrier to biomass were found to affect the syngas composition, with temperature also playing a significant role in CLG gas yield. The possible reaction mechanism suggested that variations in Ca may be the main factor in gas composition fluctuation.