Sustainable Mining and Metallurgy

Phosphogypsum is a bulk solid waste produced in the process of phosphoric acid hydrometallurgy, and its stacking has caused serious harm to the environment. Aiming at the problem that phosphogypsum is difficult to be recycled due to low whiteness and high SiO2 content, the influence of kerosene, sodium oleate and waste engine oil on flotation purification of phosphogypsum was studied by taking phosphogypsum produced by a phosphorus chemical enterprise in Guizhou as the research object. The results show that waste engine oil can effectively remove impurities such as SiO2 and organic matter in phosphogypsum, and the flotation effect is the best. The optimum conditions for the removal of phosphogypsum by waste engine oil are as follows: the pH value of pulp is 2.0, the concentration of flotation pulp is 20%, the amount of waste engine oil is 40g/t, and the amount of MIBC is 300g/t. Under the optimum experimental conditions, the concentrate yield is 91.72%, the whiteness is 63.43%, the grade is 97.54%, and the effective separation of dihydrate gypsum and organic matter is realized. This study has important guiding significance for the subsequent realization of resource and high-value utilization of phosphogypsum.