榆林煤水蒸气气化条件下钾的迁移行为研究  

Migration behavior of potassium under condition of steam gasification of Yulin coal

作　　者：韦兵 陈倩 王伟成 张万祥 陶睿旻 窦艺帆 王兴军 WEI Bing;CHEN Qian;WANG Wei-cheng;ZHANG Wan-xiang;TAO Rui-min;DOU Yi-fan;WANG Xing-jun(School of Resources and Environmental Engineering,East China University of Science and Technology,Shanghai 200237,China;Shanghai Engineering Research Center of Coal Gasification,Shanghai 200237,China)

机构地区：[1]华东理工大学资源与环境工程学院,上海200237 [2]上海市煤气化工程技术研究中心,上海200237

出　　处：《燃料化学学报》2022年第8期927-936,共10页Journal of Fuel Chemistry and Technology

基　　金：国家自然科学基金(U21A20319)资助。

摘　　要：本研究利用固定床反应装置、原子吸收光谱、X射线衍射法(XRD)考察负载碳酸钾的榆林煤(ZA-K)、负载碳酸钾的榆林脱灰煤(ZA-THK)、负载碳酸钾的模拟灰(采用SiO_(2)、Al_(2)O_(3)、CaO、Fe_(2)O_(3)四种氧化物配置)气化反应后的钾迁移行为,采用傅里叶红外光谱、拉曼光谱,探究ZA-K及ZA-THK在热解过程中的结构演变对钾迁移行为的影响;实验结果表明,温度越高,气化反应残渣中水溶性钾回收效率越低;三次水洗可以回收总水溶性钾的94.06%−98.80%;不溶性钾的生成是因为钾与煤灰中硅铝生成钾的硅铝酸盐物相;ZA-THK比ZA-K中的钾在气化反应过程中更容易挥发,在700−850℃下,ZA-THK中的钾挥发比ZA-K高出10.28%−44.92%。主要原因是ZA-K中的灰分会将负载的钾固定在煤灰中;也是酸洗脱灰使煤的芳香聚合度降低,煤中出现更多的小环芳香结构(2−8环)。A fixed bed reactor and atomic absorption spectroscopy were used to investigate potassium recovery efficiency of Yulin coal loaded with potassium carbonate(ZA-K),Yulin demineralized coal loaded with potassium carbonate(ZA-THK)and synthetic ash(Configurations of four oxides:SiO_(2),Al_(2)O_(3),CaO,Fe_(2)O_(3))loaded with potassium carbonate after reaction.Fourier infrared spectroscopy and Raman spectroscopy were used to study influence of structural evolution of ZA-K and ZA-THK on migration of potassium during pyrolysis.The results show that the yield of water-soluble potassium decreases with increasing temperature.Three times water washing could recover 94.06%−98.80%of the total water-soluble potassium.Formation of insoluble potassium is due to the phase of potassium aluminosilicate formed by potassium,silicon and aluminum in the coal ash.Potassium is easier to volatilize from ZA-THK than that from ZA-K.At 700−850℃potassium in ZA-THK is volatilized 10.28%−44.92%higher than that of ZA-K,resulting from that the ash in ZA-K would fix the loaded potassium in coal ash.Another reason may be caused by decrease in the degree of aromatic polymerization of ZA-THK through demineralization process,leading to more small-ring aromatic structures(2−8 rings)appearing in the coal.

关 键 词：催化气化 钾的迁移行为 回收效率 

分 类 号：TQ54[化学工程—煤化学工程]