Reactions between P2O5 and calcium phosphate in kiln phosphoric acid

被引：0

作者：

Lü L. ^{[1
]}

Liang B. ^{[1
]}

Liu Q. ^{[1
]}

Liu W. ^{[1
]}

Yang H. ^{[1
]}

Wu P. ^{[1
]}

Li C. ^{[1
]}

机构：

[1] School of Chemical Engineering, Sichuan University, Chengdu, 610065, Sichuan

来源：

Li, Chun (lic@scu.edu.cn) | 1600年 / Materials China卷 / 67期

关键词：

Calcium metaphosphate; Calcium pyrophosphate; Chemical processes; Fouling; P[!sub]2[!/sub]O[!sub]5[!/sub] back absorption; Rotary kiln phosphoric acid; Sintering;

D O I：

10.11949/j.issn.0438-1157.20160688

中图分类号：

学科分类号：

摘要：

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 P2O5 at 1000-1300℃ with almost pure calcium pyrophosphate at 1300℃. © All Right Reserved.

引用

页码：4399 / 4405

页数：6

共 24 条

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