Method for producing urea phosphate with wet-process phosphoric acid as raw material by dilution crystallization

Abstract

The invention relates to a method for producing urea phosphate with wet-process phosphoric acid as a raw material by dilution crystallization. The technical scheme is as follows: adding wet-process phosphoric acid, urea and acetone into a crystallization kettle, crystallizing urea phosphate crystals by changing a fed-batch rate of a dilution agent acetone, performing solid-liquid separation afterthe crystallization is completed, and washing and drying a filter cake to obtain urea phosphate. The method has the advantages of significantly reducing energy consumption of the industrial crystallization operation for producing urea phosphate with wet-process phosphoric acid as the raw material, and improving the quality of the crystallization product, avoids the disadvantages that a suspensiondensity of a crystallization mother liquid in an evaporation crystallization or cooling crystallization process is continuously increased, and can effectively reduce fragmentation and aggregation phenomena of the crystallization product.

Description

technical field [0001] The invention belongs to the technical field of phosphorus chemical production, and in particular relates to a method for producing urea phosphate by dissolution and crystallization of wet-process phosphoric acid as a raw material. Background technique [0002] Urea phosphate (urea phosphate) is a fine chemical product widely used in animal husbandry, industry, agriculture and other fields. In animal husbandry, urea phosphate is not only a legal category I additive for the feed industry of the European Community, but also recommended by the Food and Agriculture Organization of the United Nations. Special nutrient additives for ruminants and phosphorus supplements have broad market prospects and great potential. Urea phosphate is a complex compound obtained by the reaction of equal amounts of phosphoric acid and urea, and its chemical formula is CO(NH 2 ) 2 –H 3 PO 4 At present, most foreign countries use wet-process phosphoric acid as raw material ...

AI Technical Summary

Problems solved by technology

Due to the large specific heat and latent heat of evaporation of water, and the high solubility of urea phosphate in aqueous solution, the viscosity of urea phosphate evaporation crystallization liquid is relatively large and the concentration is high, resulting in high energy consumption in the evaporation and crystallization of urea phosphate. The decompression operation can properly reduce its evaporation operation temperature, but its overall production cost is still relatively high

Images