Abstract： Astrakanite resources are rich in the northwest of China, and it is of great significance to process and utilize them efficiently and comprehensively. Based on the phase equilibrium characteristics of Na2SO4-MgSO4-K2SO4-H2O quaternary system at 0 ℃, the technology of processing and separating bloedite by potassium sulfate salting-out method was studied. The technology of producing potassium-magnesium compound fertilizer and sodium sulfate was proposed using bloedite and potassium sulfate as the raw materials, and the process calculation was carried out. Sodium sulfate was produced when reaching phase equilibrium in aqueous solution of bloedite at 0 ℃. Then potassium-magnesium compound was precipitated by adding potassium sulfate into the mother solution, which can be used as a compound fertilizer for agriculture. The remaining solution can be recycled back to the original liquid for continuous production. According to process calculations: the primary yield of sodium sulfate and magnesium sulfate can reach 82.79% and 50.19% respectively. A theoretical basis and data support for the comprehensive utilization of bloedite resources was provided.
