焙烧工艺及典型杂质对磷石膏还原分解过程影响研究  

Research on effects of roasting process and typical impurities on reduction and decomposition process of phosphogypsum

作　　者：胡典 郭泽 张汉泉[2] 路漫漫[2] HU Dian;GUO Ze;ZHANG Hanquan;LU Manman(School of Optoelectronic Information and Energy Engineering,School of Mathematics and Physics,Wuhan Institute of Technology,Wuhan 430205,China;School of Resources and Safety Engineering,Wuhan University of Engineering,Wuhan 430205,China)

机构地区：[1]武汉工程大学光电信息与能源工程学院数理学院,湖北武汉430205 [2]武汉工程大学资源与安全工程学院,湖北武汉430205

出　　处：《无机盐工业》2024年第7期88-95,共8页Inorganic Chemicals Industry

基　　金：武汉工程大学研究生教育创新基金资助项目(CX2022574)。

摘　　要：磷石膏是湿法磷酸工业副产物,因杂质含量高,种类繁杂而难以利用,堆存量巨大。以磷石膏原矿、纯化磷石膏为原料进行还原分解研究,揭示了焙烧工艺和杂质对磷石膏高温分解制备CaS过程的影响规律,结果表明:磷石膏原矿、纯化磷石膏分解反应在60 min时趋于平衡,反应烧失度分别可达47.77%、54.44%;产品在焙烧温度为900℃、还原剂配比为15%(质量分数,下同)以上时无CaSO_(4)残留。磷石膏转化成CaS的最佳条件为焙烧时间为60 min、焙烧温度为950℃、还原剂配比为30%,在此条件下纯化磷石膏组还原分解产物CaS质量分数最高可达76.33%,高于同条件下磷石膏原矿组的57.37%。在磷石膏中掺杂一定量SiO_(2)、NaF、Ca_(3)(PO_(4))_(2),通过与反应中间产物CaO结合可使产品CaS质量分数分别降低1.41%~12.27%、0.61%~11.48%、1.85%~4.82%。Phosphogypsum is a byproduct of industrial wet phosphoric acid production,but because of its high impurity content,it is difficult to utilize,resulting in a huge stockpile.A reduction and decomposition study was conducted using phosphogypsum raw ore and purified phosphogypsum as raw materials,revealing the effects of roasting process and impurities on the hightemperature decomposition of phosphogypsum to prepare CaS.The results showed that the decomposition reaction of phosphogypsum raw ore and purified phosphogypsum tended to equilibrium at 60 min,and the reaction loss on ignition could reach 47.77%and 54.44%,respectively.When the product was calcined at 900℃and the reducing agent ratio was above 15%(mass fraction,the same below),there was no residual CaSO_(4).The best conditions for the conversion of phosphogypsum into CaS were:the roasting time of 60 min,the roasting temperature of 950℃and the reducing agent ratio of 30%.Under the same conditions,the CaS content of the reduced decomposition products of the purified phosphogypsum group was up to 76.33%,which was higher than that of the phosphogypsum raw ore group under the same conditions(57.37%).A certain amount of SiO_(2),NaF and Ca_(3)(PO_(4))_(2) were doped in phosphogypsum,and the CaS content of the product could be reduced by 1.41%~12.27%,0.61%~11.48%and 1.85%~4.82%,respectively by combining with the reaction intermediate product CaO.

关 键 词：磷石膏 热分解 CAS 杂质 机理 

分 类 号：TQ177.375[化学工程—硅酸盐工业]