Production method of feed-grade tricalcium phosphate

Abstract

The invention discloses a production method of feed-grade tricalcium phosphate. The method comprises the following steps: 1, drying of phosphorus rock powder; 2, mixing and ball milling; 3, disc granulation; 4, calcination defluorination; 5, cooling, crushing and sieving; 6, ball-milling of a semi-finished product; 7, screening deironing; and 8, product packaging. The method has the following advantages: 1, the raw material component and the granularity range of the phosphorus rock powder are prescribed; 2, addition of a sodium salt to raw materials facilitates decomposition defluorination of phosphorus rocks; 3, addition of phosphoric acid to the raw materials improves the content of phosphorus in the above product and facilitates granulation and calcination defluorination; 4, addition of steam in the calcining process promotes decomposition defluorination of the phosphorus rocks; 5, the product goes through the area of an electromagnet or a permanent electromagnet to remove iron fillings and other metal impurities, so operation control is simple, and the impurity removal efficiency is high; and 6, calcination tail gas is fully used to produce saturated steam and superheated steam, so energy is saved, and the energy consumption and the production cost are reduced. The method is suitable for producing the feed-grade tricalcium phosphate product.

Description

technical field [0001] The present invention relates to phosphates, especially to calcium phosphates, and more particularly to tricalcium phosphate. Background technique [0002] The sintering technology of feed-grade tricalcium phosphate includes high-silicon method, low-silicon method, low-alkali method, sodium salt phosphoric acid method and phosphoric acid method. These methods have realized industrial production in foreign countries. The high silicon method mainly utilizes various tailings, but the product P 2 o 5 The content is low, the sintering temperature is close to the melting point, it is easy to form rings in the kiln, and the operation is unstable, so it has been eliminated; the P in low-silicon products 2 o 5 The content is higher, but the requirements for phosphate rock are relatively strict, and the firing temperature is high, so it is not used in industrial production; the low-alkali method is not as strict as the low-silicon method for raw materials, bu...

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Problems solved by technology

The high silicon method mainly utilizes various tailings, but the product P 2 o 5 The content is low, the sintering temperature is close to the melting point, it is easy to form rings in the kiln, and the operation is unstable, so it has been eliminated; the P in low-silicon products 2 o 5 The content is higher, but the requirements for phosphate rock are relatively strict, and the firing temperature is high, so it is not used in industrial production; the low-alkali method is not as strict as the low-silicon method for raw materials, but the firing temperature is closer to the softening point of the ingredients, and the operation is easier. Difficult to control; at present, heavy oil is mainly used for industrial production in my country, and a certain amount of Glauber's salt or NaCl is added to the raw material. These production technologies have high product cost, high fluorine content, unstable product quality, and small output. shortcoming

[0003] At present, the patent applications related to the production method of feed-grade tricalcium phosphate include No. 011127910 "Using phosphorus-containing waste liquid to produce feed-grade tricalcium phosphate", No. ZL021280363 "Method for producing feed-grade defluorinated tricalcium phosphate by secondary sintering", No. 20071005756871 "Using Industrial Production Sodium Hypophosphite Waste Residue to Produce Feed Grade Tricalcium Phosphate Method", No. 2014105396753 "A Method for Producing Feed Grade Tricalcium Phosphate", although these methods can produce feed grade tricalcium phosphate, but still There are defects of unstable product quality and low output

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