Acidolysis method of magnesium-containing phosphate rock

Abstract

The invention discloses an acidolysis method of magnesium-containing phosphate rock. The method provided by the invention is characterized by comprising the following steps of: carrying out acidolysis on the magnesium-containing phosphate rock to obtain a water-soluble calcium, magnesium and phosphoric acid containing acidolysis solution, carrying out acidolysis on the phosphate rock by using the generated phosphoric acid to generate Ca(H2PO4)2.H2O solid, performing a reaction between H2SO4 and water-soluble calcium to generate high-pureness calcium sulfate whisker, and performing a reaction between water-soluble magnesium and phosphor in the acidolysis solution and NH3 to generate character separation magnesium ions of a MgNH4PO4 solid so as to realize complete high-efficiency comprehensive utilization of the acidolyzed magnesium-containing phosphate rock. The focus of the invention is to change magnesium ions into controllable parameters which are beneficial to circulation of the acidolysis solution. The magnesium-containing phosphate rock can be efficiently utilized, and also the compound magnesium ammonium phosphate can be used to realize the separation of phosphor magnesium from a circulation medium HCl or HNO3 or CaCL, Ca(NO3)2, thus realizing the combination and combined production with a present ammonium phosphate and phosphor product processing technology. The method provided by the invention has advantages of concise technology, less investment, low energy consumption, low cost, high benefit and no discharge of ''three wastes (waste gas, wastewater and industrial residue)'', and fully presents great business value and great resource value of the high magnesium-containing phosphate rock.

Description

Technical Field: [0001] The invention relates to a method for acid hydrolysis of phosphate rock, and more specifically to an acid hydrolysis method for complete and comprehensive utilization of magnesium-containing phosphate rock. Background technique: [0002] In the "Method for Acid Hydrolysis of Phosphate Rock" (publication number CN1962421A) published by the inventor, its technical solution includes the following steps: [0003] a. Use acid to react with phosphate rock to generate an acid hydrolysis solution containing water-soluble calcium and phosphoric acid; the acid contains HCl or HNO 3 , Or H 3 PO 4 , Or a mixed acid composed of the three in any ratio; HCl includes H 2 SO 4 The HCl gas generated by the reaction with KCl or NaCl is the HCL solution absorbed by the acid hydrolysis solution. [0004] b. Separate the acid hydrolysate, and use phosphorus-containing compounds to react with phosphoric acid in the acid hydrolysate to generate Ca(H 2 PO 4 ) 2 ·H 2 O crystal solids; ...

AI Technical Summary

Problems solved by technology

Magnesium Ammonium Phosphate MgNH 4 PO 4 It is obtained by the action of magnesium salt solution and ammonium phosphate solution, and the manufacturing cost is relatively high. This long-acting fertilizer component is contained in the current ammonium phosphate products

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