磷酸二氢铵脱除气相氯化钾的模拟与实验  

Simulation and experiments of removal process of gaseous KCl by ammonium dihydrogen phosphate

作　　者：韩奎华[1] 齐建荟[1] 李辉[1] 路春美[1] 

机构地区：[1]山东大学燃煤污染物减排国家工程实验室,山东济南250061

出　　处：《化工学报》2014年第3期1093-1098,共6页CIESC Journal

基　　金：国家自然科学基金项目(51206096)~~

摘　　要：脱除生物质燃烧中气相氯化钾,有助于消除受热面的积灰和腐蚀。采用热力学化学平衡分析方法探索了磷酸二氢铵脱除气相氯化钾的反应特性,考察了温度和化学计量比对反应的影响,结果表明磷酸二氢铵在700～950℃范围内可以有效地将气相氯化钾主要转化为磷酸氢二钾。利用X射线衍射分析对沉降炉实验得到的反应产物进行物相分析,探索了磷钾摩尔比、停留时间、温度对磷酸二氢铵脱除氯化钾的影响,实验结果表明增加停留时间以及磷钾摩尔比均可以促进KCl的脱除,停留时间3 s,磷钾摩尔比为1时,700～1000℃下的反应产物中未检测到物相KCl,而生成了磷酸氢二钾、磷酸二氢钾、偏磷酸钾、焦磷酸钾、磷酸钾铵、磷酸二氢铵钾等产物。结果有助于深入研究磷酸二氢铵用于脱除燃烧中碱金属离子。Reduction of gaseous KC1 producing in biomass combustion can help eliminate corrosion and ash deposition on the heating surface. Reaction characteristics of gaseous KC1 and ammonium dihydrogen phosphate （ADP） are studied by using chemical thermal equilibrium analysis, including the effect of temperature and stoichiometric ratio. The simulation results show that gaseous KC1 can be effectively transformed into K2HPO4 in a temperature range of 700--950℃. The reaction products obtained in the experiment using drop tube furnace system are analyzed by X-ray diffraction to examine the effects of mole ratio of P/K （a）, residence time and temperature on KC1 removal by ADP. The experimental results show that prolonging reaction time and increasing P/K mole ratio can promote conversion of gaseous KC1. At the experimental conditions： the temperature range of 700--1000℃, mole ratio of P/K of 1, residence time of 3 s, there is no KC1 in the products （not detected by XRD）. That means that KC1 has be effectively transformed into dipotassium hydrogen phosphate （K2HPO4）, potassium dihydrogen phosphate （KH2PO4）, potassium metaphosphate [（KPO3）n], potassium pyrophosphate （K4P207）, potassium ammonium phosphate, potassium-ammonium dihydrogen phosphate etc. These results will be helpful for further study removing gaseous alkali metal ions by ammonium dihydrogen phosphate.

关 键 词：生物质 燃烧 氯化钾 磷酸二氢铵 脱除 

分 类 号：TQ038[化学工程]