化工学报2016，Vol.67Issue(10)：4399-4405,7.DOI:10.11949/j.issn.0438-1157.20160688
窑法磷酸中磷酸钙对P2O5反吸过程
Reactions between P2O5 and calcium phosphate in kiln phosphoric acid
摘要
Abstract
Side reactions of gaseous product P2O5 with phosphate ores (so-called P2O5 back absorption) in rotary kiln produce large quantities of low melting point solid products, which could form a kiln ring, block material flow and cause unstable operation of the kiln. The back absorption of gaseous P2O5 with calcium phosphate was studied at different temperatures and the products were characterized for P2O5 content, morphology, phase composition, structure and thermal stability by chemical analysis and other techniques of SEM, XRD, IR, Raman, TG and DSC. The experimental results show that temperature significantly affected the back absorption, which was occurred above 500℃. Calcium metaphosphate was formed at 500—900℃ with almost pure calcium metaphosphate at 900℃. Calcium metaphosphate decomposed into calcium pyrophosphate and P2O5at 1000—1300℃ with almost pure calcium pyrophosphate at 1300℃.关键词
窑法磷酸/P2O5反吸/偏磷酸钙/焦磷酸钙/烧结/结垢/化学过程Key words
rotary kiln phosphoric acid/P2O5 back absorption/calcium metaphosphate/calcium pyrophosphate/fouling/sintering/chemical processes分类
信息技术与安全科学引用本文复制引用
吕莉,梁斌,刘强,刘维燥,杨宏辉,吴潘,李春..窑法磷酸中磷酸钙对P2O5反吸过程[J].化工学报,2016,67(10):4399-4405,7.基金项目
四川大学科技计划项目（SCU2015C002）。 （）
