Analysis of Phosphogypsum's Physical and Chemical Properties and Making of Anhydrite Cement from phosphogypsum

摘要

The phosphogypsum (PG) sample produced as the waste of the phosphoric acid fertilizer plant from Guizhou, China was studied for its properties and as a material for anhydrite cement. The impurity content, type and distribution, as well as thermal behavior and solubility of the PG were carefully studied by XRD, DTA techniques and gravimetric determination. The physical properties of the sample were studied as per the China Standard GB175-2007. The mineralogical studies were determined by XRD. The results showed that the impurities of PG are mainly water-soluble P_2O_5, F, organics and P_2O_5 and F in the gypsum lattice which has entered in to solid solution with gypsum as well as the insoluble Ca_3(PO_4)_2 and CaF_2. Experimental datum showed that a suitable anhydrite can be produced by heating PG at 1000°C and PG up to 60% used can be as a main raw material in production of anhydrite cement.