新型高铝修饰钙基吸收剂抗烧结抗磨损机理研究

Calcination/ carbonation of calcium based sorbent in fluidized beds is one of the most feasible technologies for CO2 capture. However, great expansion and shrinkage of crystal structure of calcium based sorbents are created during the calcination/ carbonation process, which results in structure collapse and great attrition. To stabilize the crystal structure or modify a relative stable structure of the sorbents presents important significance in decreasing CO2 capture performance and attrition resistance. Al2O3 of high melting point may restrain crystal structure collapse and attrition. This project aimed to use high alumina media like high alumina fly ash, abandoned high alumina refractories, high alumina cement, ect. as modifiers to investigate the mechanism of anti-sintering and attrition resistance of the novel modified calcium based sorbent, which will provide theoretical basis for CO2 capture at low cost. The optimum modified method and CO2 capture performance of the novel modified calcium based sorbent will be studied on the basis of TGA, twin fixed beds and a fluidized bed. The changes of crystal structure and mechanism of anti-sintering of the novel sorbents will also be investigated based on the microstructure, crystal growth and defect concentration of the sorbents. The particle size distribution will also be examined under the conditions of alternate temperature, atmosphere and calcination/ carbonation to study the attrition mechanism and establish the criteria of enhancing attrition resistance of sorbents which will provide solid theory basis for searching economic and effective modified method.

钙基吸收剂流化床循环煅烧/碳酸化捕集CO2是目前最具可行性的CO2捕集技术之一。然而，在CO2吸收和解析过程中，吸收剂晶体结构膨胀和收缩较大，造成结构塌陷，如何保持稳定或修饰出较稳定的晶体结构以减缓吸收剂烧结和磨损，对该技术发展具有重要研究意义。高熔点Al2O3对抑制晶体结构塌陷和磨损可能起积极作用。本项目以高铝粉煤灰、废弃高铝耐火材料、高铝水泥等作修饰剂，研究新型高铝修饰钙基吸收剂在循环过程中抗烧结抗磨损机理，为CO2低成本捕集提供充分理论依据。基于TGA、固定床和流化床系统，研究最佳修饰方法及新型高铝修饰钙基吸收剂循环碳酸化规律；从微观结构、晶粒生长和缺陷浓度等角度揭示新型高铝修饰钙基吸收剂晶体结构变化规律及抗烧结机理；对吸收剂在交变温度、气氛和碳酸化/煅烧条件下的粒径分布统计考察其磨损机制，形成提高吸收剂抗磨损性能判别标准，为寻找更经济有效的改性方法提供理论依据。

钙基吸收剂流化床循环煅烧/碳酸化捕集CO2是目前最具可行性的CO2 捕集技术之一。在循环煅烧/碳酸化过程中，吸收剂烧结及孔隙堵塞是造成其循环碳酸化性能随循环次数增加衰减迅速的主要原因，维持吸收剂高效持续的碳酸化性能，对该技术发展具有重要研究意义。高熔点Al2O3 对减缓吸收剂烧结和磨损可能起积极作用。本项目以高铝粉煤灰、高铝水泥等作修饰剂，基于TGA和固定床系统，研究各种改性方法对高铝粉煤灰修饰钙基吸收剂的影响作用，获得了最佳修饰方法及新型高铝修饰钙基吸收剂循环碳酸化规律；从微观孔隙结构、物相结构等角度揭示新型高铝修饰钙基吸收剂在循环反应过程中的孔隙结构变化以及晶体结构变化规律，分析其对修饰钙基吸收剂的抗烧结影响机制；在流化床系统上对改性钙基吸收剂在交变温度、气氛和碳酸化/煅烧条件下反应过程中颗粒粒径分布规律进行考察，获得了改性钙基吸收剂的磨损性能得以提高的机制，达到课题预期的研究目的，同时为后续开发高效经济的钙基吸收剂提供有益的理论基础。发表论文10篇，其中SCI收录论文4篇，EI收录论文4篇，国内核心期刊论文1篇，会议论文1篇。获得教育部自然科学奖二等奖1项，申请国家发明专利2项；培养硕士研究生3名，均已毕业。