SiC还原磷灰石气化脱磷的热力学机理研究  

Thermodynamic Mechanism of Gasification Dephosphorization of SiC Reduced Apatite

作　　者：贺腾 罗果萍[1] 张婧[1] 张国成[1,2] 纪祥辉 HE Teng;LUO Guoping;ZHANG Jing;ZHANG Guocheng;JI Xianghui(School of Material and Metallurgy,Inner Mongolia University of Science and Technology,Baotou 041010,China;Department of Chemistry,Baotou Teachers College,Baotou 014010,China)

机构地区：[1]内蒙古科技大学材料与冶金学院,内蒙古包头014010 [2]包头师范学院化学学院,内蒙古包头014010

出　　处：《金属矿山》2022年第8期131-137,共7页Metal Mine

基　　金：国家自然科学基金项目(编号:51664045)。

摘　　要：以SiC为还原剂,Na_(2)CO_(3)、Al_(2)O_(3)和SiO_(2)为辅助脱磷剂研究磷酸钙的还原气化脱磷机理。利用Fact Sage7.1热力学软件计算以及试验分析了不同温度以及辅助脱磷剂添加量对气化脱磷的影响。结果表明:脱磷反应在无液相参与时还原程度较低,在1300℃下气化脱磷率为17.83%。辅助脱磷剂Na_(2)CO_(3)添加量分别为6%、8%和10%时生成液相,气化脱磷率显著提高。X射线衍射分析结果显示,产物中硅酸钙盐较多,与模拟中脱磷反应的固相产物一致。最佳的辅助脱磷剂Na_(2)CO_(3)添加量为8%、Al_(2)O_(3)添加量为7.7%、SiO_(2)添加量为14.06%,在1300℃下对应的气化脱磷率为86.50%。当辅助脱磷剂Na_(2)CO_(3)添加量达到10%时,气化脱磷率降低到35.79%,检测到固相产物中有Na_(2)Ca_(3)Al_(2)(PO_(4))_(2)(SiO_(4))_(2)存在,这是霞石与磷酸钙在1300℃下的反应产物,导致磷元素被固定在其中无法气化脱除,从而降低了气化脱磷率。The reduction gasification dephosphorization mechanism of calcium phosphate was studied with SiC as reducing agent and Na_(2)CO_(3),Al_(2)O_(3)and SiO_(2)as auxiliary dephosphorization agents.FactSage 7.1 thermodynamic software was used to calculate and test the influence of different temperatures and the amount of auxiliary dephosphorization agent on gasification dephosphorization.The results show that the reduction degree of dephosphorization reaction is low without liquid phase,and the dephosphorization rate is 17.83%at 1300℃.When Na_(2)CO_(3)dosage is 6%,8%and 10%systems were added to assist dephosphorization agent to generate liquid phase,the gasification dephosphorization rate was significantly increased.By X-ray diffraction analysis,there are more calcium silicate salts in the product,which is consistent with the simulated dephosphorization product.The optimal supplemental amount of auxiliary dephosphorization agent Na_(2)CO_(3),Al_(2)O_(3),SiO_(2)is 8%,7.7%,14.06%respectively.The corresponding gasification dephosphorization rate is 86.50%at 1300℃.When the addition amount of Na_(2)CO_(3)reaches 10%,the gasification dephosphorization rate decreases to 35.79%,Na_(2)Ca_(3)Al_(2)(PO_(4))_(2)(SiO_(4))_(2)was detected in the solid phase product,which was produced by nepheline and calcium phosphate at 1300℃.As a result,phosphorus was fixed in the product and could not be gasification dephosphorization,thus reducing the gasification dephosphorization rate.

关 键 词：SIC 气化脱磷 热力学机理 辅助脱磷剂 

分 类 号：TD925.7[矿业工程—选矿]