钙循环是煤基低碳利用的重要技术路径之一。煅烧过程是钙循环中的关键环节，需要通过煤的富氧燃烧供热实现吸附剂分解再生进而捕集CO2。然而，目前对钙循环的研究多基于N2/CO2等理想煅烧气氛，而与实际煅烧环境相差甚远。初步研究显示，煤富氧燃烧气氛中的水蒸气和SO2对钙基CO2吸附剂的再生过程有着重要影响。本项目拟针对水蒸气/SO2作用下的吸附剂分解再生动力学特性与机制展开研究。通过实验研究与基于密度泛函的分子模拟，弄清水蒸气加速吸附剂分解再生的规律及催化机理；改进变晶粒粒径数值模型，研究伴随有硫酸化反应的单颗粒吸附剂分解过程中的耦合行为、影响因素及规律；通过进一步的实验研究，揭示水蒸气与SO2共同作用下的吸附剂CO2脱附特性与涉及的协同竞争机制，从而调控与优化钙基CO2吸附剂颗粒结构参数及煅烧过程工况。本项目的实施将为钙循环煤基低碳利用技术的发展提供基础科学依据。

Calcium looping (CaL) is one of the most important technical ways in achieving low-carbon coal utilization. Calcination is the key stage in calcium looping, where sorbents are regenerated using the heat supplied by oxygen-enriched combustion of coal and then ready for CO2 capture. However, most of the existed researches on calcium looping are conducted under the ideal calcination atmosphere of N2/CO2 mixtures, which is far from the real operating conditions. Preliminary studies show that the decomposition process of calcium-based sorbents changes significantly with the presence of steam and SO2 produced in the oxygen-enriched combustion of coal. This project will focus on this issue and study the kinetic characteristics and mechanism in the regeneration of sorbents upon the impact of steam and SO2. The law and the catalytic mechanism on the acceleration of sorbents’ decomposition by steam will be revealed by the combined experiment and molecular simulation using the density functional theory. A changing grain size model will be developed to study the coupling behavior, the key factors and the influences during the simultaneous decomposition and sulfation within a single sorbent particle. Further experiments will be performed to understand the CO2 desorption features of the sorbents and the synergistic and competitive mechanism with the combined effect of steam and SO2, thus properties of sorbent particles and the calcination conditions in calcium looping can be adjusted and optimized. The implementation of the project will provide scientific basis for the development of the CaL-based low-carbon coal utilization technology.