镁渣固定磷石膏中可溶磷的基础研究

Basic study on fixing soluble phosphorus in phosphogypsum with magnesium slag

为了降低磷石膏中可溶性磷对其工程应用的影响,分别以镁渣、镁渣-磷酸二氢钾为固化剂对磷石膏中的可溶磷进行固化,探究镁渣、镁渣-磷酸二氢钾用量对磷石膏中可溶磷固定效果的影响。通过紫外-可见分光光度计法、培养微生物法评价可溶磷的固定效果,采用扫描电镜观察两种体系产物的微观形貌。结果表明:镁渣的加入能够有效固定磷石膏中的可溶磷;当镁渣质量分数为15%、磷酸二氢钾质量分数为5%时固磷效果较优,固定率为30.00%,该浓度下培养的大肠杆菌个数比原状磷石膏培养的大肠杆菌个数少54.49%,磷石膏中可溶磷转化为圆柱状的磷酸镁和板块状的磷酸钾镁。该研究方法固定了磷石膏中的可溶磷并将其转化为具有胶凝性的磷酸镁和磷酸钾镁,为磷石膏的直接利用提供了新途径。

In order to reduce the influence of soluble phosphorus in phosphogypsum on its engineering application,soluble phosphorus in phosphogypsum was cured by using magnesium slag and magnesium slag‐potassium dihydrogen phosphate as the curing agent,respectively,and the influence of magnesium slag dosage and magnesium slag‐potassium dihydrogen phos‐phate dosage on the fixation effect of soluble phosphorus in phosphogypsum was explored.The fixation effect of soluble phos‐phorus was evaluated using ultraviolet‐visible spectrophotometry and microbial cultivation methods,and the microscopic morphology of the products in both systems was observed using scanning electron microscopy.The experimental results showed that the addition of magnesium slag could effectively fix soluble phosphorus in phosphogypsum.The effect of phos‐phorus fixation was better when the addition of magnesium dregs was 15%and the addition of potassium dihydrogen phos‐phate was 5%,the fixation rate was 30.00%,the number of E.coli cultured in this concentration was 54.49%less than that cultured in the original phosphogypsum,and the soluble phosphorus in the phosphogypsum was transformed into magne‐sium phosphates in the form of cylindrical and potassium magnesium phosphates in the form of slabs.The method fixed soluble phosphorus in phosphogypsum and converted it into gelling magnesium phosphate and potassium magnesium phos‐phate,which provided a new way for the direct utilization of phosphogypsum.