Potassium sulfate preparation system and potassium sulfate preparation method

Abstract

The invention relates to a potassium sulfate preparation method, which comprises: S1, adding ammonium sulfate into a salt dissolving groove to prepare a solution with a saturated ammonium sulfate concentration, introducing the solution of the salt dissolving groove into a crystallizer, adding solid potassium chloride to the crystallizer, carrying out a reaction with the solution, and forming crystal; S2, carrying out gravity separation on the solution and the crystal after the reaction in the step S1 to obtain an upper layer slurry containing ammonium chloride solid, and a lower layer slurry containing potassium ammonium sulfate and potassium sulfate solid; and S3, carrying out solid-liquid separation on the slurry containing potassium ammonium sulfate and potassium sulfate solid, whereinthe liquid phase is a mother liquor 2, the solid phase comprising potassium ammonium sulfate and potassium sulfate is fed into a converter, and a saturated potassium chloride solution is added to theconverter and reacts with potassium ammonium sulfate to form potassium sulfate. According to the present invention, the potassium sulfate product with the potassium oxide content of more than 50% by mass is prepared through gravity selective separation and secondary conversion so as to avoid the use of the catalyst, reduce the evaporation amount, achieve the simple technology, easily control the condition and achieve the low cost.

Description

technical field [0001] The invention relates to a preparation method of potassium sulfate, in particular to a preparation system and method for preparing potassium sulfate with high recovery rate by double decomposition method using potassium chloride and ammonium sulfate as raw materials at normal temperature. Background technique [0002] Potassium sulfate is an important chlorine-free high-quality potassium fertilizer. Potassium is one of the three major nutrients for plants, and sulfur is an intermediate nutrient element required by plants. Potassium sulfate is a more suitable multi-component fertilizer than potassium chloride for chlorine-avoiding economic crops such as tobacco, citrus, tea, sugarcane, etc., and its application range and effect are far better than potassium chloride. In addition, potassium sulfate is also a basic chemical raw material, which is widely used in medicine, glass and dye industries. At present, the annual demand for potassium sulfate in my ...

AI Technical Summary

Problems solved by technology

[0005] Chinese patent CN1168350A proposes that potassium chloride and ammonium sulfate are made into high-temperature saturated solutions respectively, then the two solutions are mixed, and then the main product potassium sulfate is crystallized through cooling, and the filtrate is evaporated to remove water to obtain the by-product potassium chloride ammonium, but potassium The conversion rate is only 70%, and the evaporation energy consumption is high, and the quality is not stable

This process requires high temperature heating, high energy consumption, and high temperature corrosion has high requirements on equipment materials, so it is not economical

Images