磷石膏和硫化钙反应过程的熔融特性研究

为探讨影响磷石膏分解制硫酸生产过程中回转窑内结皮、结圈和粘结堵塞等问题的主导因素,以磷石膏和硫化钙为原料,采用微机灰熔融性测定仪研究了不同添加剂和反应气氛对CaSO4和CaS固-固反应中熔融软化温度(ST)的影响。结果表明,提高磷石膏制硫酸反应中熔融软化温度的有效添加剂是高岭土和SO2、CO2、N2的混合气氛,而起助熔作用的添加剂是SiO2、AlPO4、FePO4.2H2 O、Na2 SiF6等。

Research on the melting characteristics during the reaction process of phosphogypsum and calcium sulfide

To explore the dominant factors that cause the problems such as coating formation,ring formation,bonding and blocking,etc.,in rotary kiln used in the industrial production of sulfuric acid,the melting characteristics of decomposition process of phosphogypsum are investigated.With phosphogypsum and calcium sulfide as raw materials,ash melting point measuring instrument is used to study the effects of additives and reaction atmosphere on the melting softening temperature(ST) in the CaSO4 and CaS solid-solid reaction.The results show that,the effective additive of increasing the melting softening temperature during the decomposition of phosphogypsum are kaolin and mixed atmosphere containing SO2,CO2 and N2,respectively.The additives such as SiO2,AlPO4,FePO4·2H2O,Na2SiF6,and so on,play a role in fluxing action.