水蒸气强化纤维素模板改性钙基吸附剂固碳性能及强度

Enhanced CO_(2) capture performance and strength of cellulose-templated CaO-based pellets with steam reactivation

采用挤出-滚圆法制备了纤维素模板水泥支撑钙基吸附剂颗粒,基于双固定床反应器探究了煅烧时蒸汽活化对改性吸附剂的CO_(2)捕获性能、力学性能和微观结构的影响特性。实验结果表明,在热致烧结和气氛诱导烧结共同作用下,吸附剂颗粒形成较稳定的孔隙结构,固碳量和力学强度均维持在较高水平。煅烧时通入10%(体积分数)水蒸气,含10%(质量分数)纤维素和5%(质量分数)水泥的吸附剂第20次循环CO_(2)捕获量为0.32g/g,相比原始吸附剂(0.138g/g)和未活化的合成吸附剂(0.20g/g)分别提高了132%和60%。且活化后颗粒平均破碎强度为14.7N,比无蒸汽条件下增强约2.7倍。50次长循环测试后,其强度进一步提升至20.5N。煅烧时蒸汽活化可同时显著提升吸附剂CO_(2)捕获量和力学性能。

Cellulose-templated CaO-basted pellets were prepared by an extrusion-spheronization method.The effects of steam addition during calcination on the CO_(2) capture capacity,mechanical properties,and microstructure of the modified sorbents were investigated based on a double fixed-bed reactor.The experimental results showed that the sorbent pellets formed stable pore structures under the combined effect of thermal sintering and atmosphere-induced sintering,ensuring that the CO_(2) capture capacity and mechanical strength were maintained at a high level.The CO_(2) uptake of the sorbent with 10%(mass ratio)cellulose and 5%(mass ratio)cement as well as 10%volume fraction steam reactivation was 0.32g/g after 20cycles,which was 132%and 60%higher than the raw sorbent(0.138g/g)and the modified sorbent(0.20g/g)without steam injection,respectively.Moreover,the average crushing strength of the pellets calcined with adding 10%volume fraction steam into the calcination atmosphere was 14.7N,which was enhanced by about 2.7 times that without steam.The strength was further increased to 20.5N after 50 cycles.Thus,steam injection during calcination demonstrated great potential in retaining CO_(2) capture durability and improving the mechanical properties of the cellulose-templated sorbent.