Abstract:
To address climate change and reduce carbon emissions, China has pledged to peak CO
2 emissions before 2030 and achieve carbon neutrality by 2060. Currently, fossil fuels such as coal still occupy a significant proportion in China’s energy consumption structure, which is of great significance for ensuring the stability and safety of energy supply. Utilizing carbon capture technology can effectively reduce carbon emissions, even achieving near-zero emissions, thereby facilitating a steady transition in energy sources. Oxygen-enrichment combustion is the core process in carbon capture during combustion. It has advantages such as high CO
2 concentration, low capture cost, high combustion efficiency, and low pollutant emissions, and thus has broad application prospects. To broaden the fuel adaptability of oxygen-enrichment combustion technology and enhance its compatibility with industrial fields, the authors proposed a new idea of the fluidized activation technology of carbon-based raw materials. By using this technology, gas-solid activated like-gas fuel can be prepared. Subsequently, carbon capture can be achieved through oxygen-enriched combustion. Alternatively, the gas-solid activated like-gas fuel can generate CO-rich syngas via oxygen-enriched gasification, which could offer sufficient and high-grade raw materials and key reaction fundamentals for the production of chemicals with CO as the feedstock, thereby achieving the utilization of CO₂ and carbon fixation. Firstly, the basic principle of fluidized activation technology is analyzed, and the functioning mechanism of CO
2 in this process is clarified. The characteristics of the produced fuel gas and the activated semi-char from carbon-based raw materials after fluidized activation process are reviewed. The emphasis is on exploring the effects of activation temperature, molar ratio of carbon to CO
2 (C/C ratio), reaction atmosphere, oxygen concentration, and fuel type on the gas composition, gas yield, and gas calorific value, as well as the influence on the particle size distribution, microstructure, specific surface area, pore structure, carbon framework structure, and reactivity of the activated semi-char. The gasification characteristics of gas-solid activated like-gas-fuel in an O
2/CO
2 atmosphere are summarized, and the effects of fuel type, CO
2 concentration, and O
2/C molar ratio on gasification performance are compared. The combustion characteristics of gas-solid activated like-gas-fuel in an O
2/CO
2 atmosphere are also summarized, and the NO
x emission properties and reaction control mechanisms are analyzed. Finally, the fluidized activation technology is summarized and prospected, with the hope of providing a theoretical basis and data support for in-combustion carbon capture technology in the industrial field and the large-scale resource utilization of CO
2.