Process for preparing tricalcium phosphate

Abstract

The invention discloses a method for producing tertiary calcium phosphate, which is characterized by comprising the following steps: mixing powdered rock phosphate, milk of lime and mixed auxiliary agent, sintering the mixture for more than seven hours at a temperature of between 1100 and 1300 DEG C, wherein the mol rate of the powdered rock phosphate to the milk of lime is 2.0 to 3.0 according to the mol rate of CaO to P2O5, the weight of the mixed auxiliary agent is 5 to 15 percent of that of the powdered rock phosphate, and the mixed auxiliary agent is formed by mixing soluble hydrochloride and hypochlorite. In the method for producing tertiary calcium phosphate in the invention, the reaction to harmful element is realized by adopting relevant chemical reactions through the cheap and easily obtained mixed auxiliary agent to remove the harmful element so that the content of the harmful element therein is far below that of the like product, the content of fluorine is very low; when the mixed auxiliary agent is calcium chloride, sodium chloride and sodium hypochlorite, the produced tertiary calcium phosphate is particularly suitable for being used as feed additive; the raw material is cheap powdered rock phosphate, thereby the cost is greatly lowered. The method is simple and feasible and the investment is low.

Description

technical field [0001] The present invention relates to a method for producing tricalcium phosphate. Background technique [0002] Feed phosphate is an important mineral feed additive, and the consumption of feed phosphate is one of the symbols to measure the development level of a country's agriculture and animal husbandry. There are more than 20 varieties of feed phosphate abroad, including calcium salt, sodium salt, ammonium salt, potassium salt, etc., of which calcium phosphate accounts for more than 90% of its consumption. [0003] Tricalcium defluorophosphate [Ca 3 (PO 4 ) 2 ] is a white, light gray or brown amorphous powder, odorless and tasteless, with excellent physical and chemical properties, almost insoluble in water, soluble in 0.4% hydrochloric acid (equivalent to the gastric acid of poultry) or 2% citric acid (equivalent to the acidity of plant roots). Calcium defluorinated phosphate has a wide range of uses, mainly used in the manufacture of ceramics and...

AI Technical Summary

Problems solved by technology

The disadvantage of the old process is that most of the raw materials depend on high-priced industrial products, and the equipment is expensive (the price of a rotary kiln with an annual output of 10,000 tons is between 5 million and 6 million yuan), so the production cost is high and the product competitiveness is low. Moreover, the products produced by the old process have high levels of harmful substances, resulting in low quality products