CuFe_(2)O_(4)改性脱硫渣氧载体与褐煤的反应特性  

Reaction characteristics of CuFe_(2)O_(4) modified desulfurization slag oxygen carrier with lignite

作　　者：王保文[1] 刘同庆 张港 李炜光 林德顺 王梦家 马晶晶 WANG Baowen;LIU Tongqing;ZHANG Gang;LI Weiguang;LIN Deshun;WANG Mengjia;MA Jingjing(School of Energy and Power Engineering,North China University of Water Resources and Electric Power,Zhengzhou 450045,Henan,China;State Key Laboratory of High-efficiency Utilization of Coa)

机构地区：[1]华北水利水电大学能源与动力工程学院,河南郑州450045 [2]宁夏大学省部共建煤炭高效利用与绿色化工国家重点实验室,宁夏银川750021

出　　处：《化工进展》2023年第6期2884-2894,共11页Chemical Industry and Engineering Progress

基　　金：国家自然科学基金(51776073);河南省科技攻关项目(162102210233);省部共建煤炭高效利用与绿色化工国家重点实验室(2021-KF 42)。

摘　　要：基于烟气脱硫渣采用改进的提纯工艺和优化参数获得高纯度和反应活性的CaSO_(4),以此作为模板剂结合溶胶凝胶燃烧合成法制备了CuFe_(2)O_(4)改性活化并具有“核-壳”结构的CaSO_(4)-CuFe_(2)O_(4)混合氧载体。在固定床反应器上研究了还原反应温度和循环次数作用下自制CaSO_(4)-CuFe_(2)O_(4)混合氧载体与煤化学链燃烧特性,系统研究了CaSO_(4)副反应与CuFe_(2)O_(4)交互作用下不同气相硫的释放和演化。研究表明,改性脱硫渣与煤反应时,CuFe_(2)O_(4)还原产物Cu、FeO通过未反应CaSO_(4)及已还原的CaS形成的熔融界面获得了其中未能利用的晶格氧,实现了本身的原位氧化,不仅明显提高了改性脱硫渣的反应活性,促进了煤的转化,同时也促进了未反应CaSO_(4)中晶格氧的定向传递和梯级利用。进一步,综合考虑煤的碳转化率以及气相硫的释放特性,确定了改性脱硫渣与煤的最佳反应条件为900℃。而循环实验发现,CaSO_(4)-CuFe_(2)O_(4)氧载体在多次循环中CaSO_(4)副反应不能完全抑制,少量气相硫的逸出加之还原氧载体的部分烧结导致反应活性衰减。The purified and active CaSO_(4) was derived from flue gas desulfurization slag using improved purification technology and relevant parameters,which was further utilized as the template to prepare CuFe_(2)O_(4) modified CaSO_(4) mixed oxygen carrier(OC)with special“core-shell”structure via sol-gel combustion synthesis method.Effects of reduction temperature and cycle numbers on the reaction of CaSO_(4)-CuFe_(2)O_(4) mixed OC with coal were studied on the fixed bed reactor.Meanwhile,gaseous sulfur species emitted from different CaSO_(4) side reactions and their interaction with the introduced CuFe_(2)O_(4) were further investigated.The results indicated that during reaction of the CaSO_(4)-CuFe_(2)O_(4) mixed OC with coal,the reduced CuFe_(2)O_(4) products as Cu and FeO regained the unutilized lattice oxygen included in the CaSO_(4) via the solid eutectics between the unreacted CaSO_(4) and reduced CaS to realize their in situ oxidization,which not only enhanced the reactivity of the CaSO_(4)-CuFe_(2)O_(4) mixed OC and promoted coal conversion,but also benefited the directional transfer of the oxygen involved in the unreacted CaSO_(4) to reach cascade utilization of the oxygen involved in the mixed OC.Furthermore,through comprehensive consideration of carbon conversion for coal and gaseous sulfur release from CaSO_(4),optimized reaction condition was determined as 900℃.Finally,after reduction and oxidation cyclic experiments,CaSO_(4)-CuFe_(2)O_(4) OC was found to incompletely inhibit the CaSO_(4) side reactions coupled with partly sintering of the reduced OC,which caused the cyclic reactivity of the modified OC to decay.

关 键 词：煤 化学链燃烧 烟气脱硫渣 CaSO_(4)-CuFe_(2)O_(4)混合氧载体 碳转化 硫原位控制 

分 类 号：TK16[动力工程及工程热物理—热能工程]