A kind of production method of granular, function-enhanced magnesium-containing ammonium phosphate

Abstract

The invention discloses a production method for granular function-intensifying type magnesium-containing ammonium phosphate. The method comprises the following steps: taking ammonium phosphate which is 5%-50% of the total amount of the phosphoric acid required by the production and adding magnesium oxide for reacting; introducing the acquired product into liquid ammonia and neutralizing, thereby acquiring reaction slurry containing magnesium ammonium phosphate and ammonium phosphate; producing ammonium phosphate grains by utilizing the remaining 95-50% of phosphoric acid according to an original process; sending the reaction slurry to the tail part of a pelletizer; spraying and coating on the surfaces of the ammonium phosphate grains; and drying, screening and cooling, thereby acquiring the magnesium-containing ammonium phosphate product. According to the invention, the important medium element magnesium is added into the traditional ammonium phosphate product; magnesium and phosphorus have an important synergistic effect; the absorption of crops for phosphorus can be obviously promoted; the fertilizer efficiency and the use ratio of the phosphatic fertilizer can be promoted; the crop quality can be promoted; according to the method, the ammonium phosphate product can be effectively prevented from moisture absorption, decomposition and re-crystallization; the functions of resisting against dust and blocking of similar packaging oil can be achieved; a certain slow release effect can be achieved; the process according to the invention is simple, practical and efficient; the product quality is high; the economic returns are excellent; the environment is protected; the application prospect is excellent.

Description

technical field [0001] The invention belongs to the technical field of phosphorus and compound fertilizer production, and in particular relates to a method of producing granular, function-enhanced magnesium-containing phosphorus with wet-process phosphoric acid, liquid ammonia and bitter soil (magnesium oxide) as main raw materials and utilizing an existing ammonium phosphate device. Ammonium (including monoammonium phosphate, diammonium phosphate) products. Background technique [0002] Magnesium is one of the main constituents of chlorophyll molecules in plants. It can promote plant photosynthesis and growth and development, and is an important medium element necessary for crop growth. Moreover, magnesium and phosphorus have a strong synergistic effect. The presence of magnesium can significantly promote the absorption of phosphorus nutrients by crops, improve crop yield and quality, and improve the fertilizer efficiency and utilization rate of phosphorus compound fertiliz...

AI Technical Summary

Problems solved by technology

At present, the granular ammonium phosphate products at home and abroad generally have the following problems: First, due to the strong water solubility of ammonium phosphate products, the surface of the particles is prone to moisture (especially in high temperature, high humidity summer, rainy season or long-term stacking After being exposed to moisture, the surface of the product particles is prone to a certain degree of dissolution and recrystallization, which will cause problems such as "hair growth", discoloration, uneven color and instability on the surface of the product particles, as well as adhesion and agglomeration of the product particles; It is due to the moisture absorption, dissolution and recrystallization on the surface of the product particles, the surface "long hair" is easy to fall off, and a certain amount of dust is generated, which is prone to dust pollution in the links of packaging, storage, transportation and application; In order to prevent dust pollution and recrystallization on the surface of product particles, resulting in product discoloration, uneven color, instability and product agglomeration and other appearance quality problems, at present, the production of granular ammonium phosphate at home and abroad is generally used on the surface of its particles The method of spraying an appropriate amount of wrapping oil (the wrapping oil brings an appropriate amount of anti-caking agents such as organic amines); there is also a method of spraying a layer of sulfur on the surface of ammonium phosphate product particles to produce ammonium sulfocoating phosphate

But the problem that these methods exist is: (1) wrapping oil belongs to petroleum processing product, is used for wrapping ammonium phosphate product granule surface, can increase the chemical oxygen demand COD of soil after application, and contains a certain amount of heavy metals and other harmful substances in the wrapping oil. (2) Use sulfur to coat the surface of ammonium phosphate product granules to produce sulfocoated ammonium phosphate, although it can prevent moisture absorption, recrystallization, discoloration, uneven color and instability on the surface of product granules And appearance quality problems such as product agglomeration, can also increase medium amount element sulfur simultaneously, and, because elemental sulfur is basically insoluble in water, so ammonium sulfocoating phosphate product also just has certain slow-release function (mainly refers to that ammonium phosphate contains slow release of nitrogen)

However, the main feature of ammonium phosphate products is high phosphorus content, and the method of sulfur coating does not introduce magnesium, a medium element that has an important synergistic effect with phosphorus, and, in its production process, there are still difficulties in adding solid or liquid elemental sulfur As well as the safety risk of explosion caused by dust sulfur and sublimated sulfur in the production system

[0006] At present, in the existing technologies and methods, there is still no good solution to overcome the fact that the granular ammonium phosphate product does not contain magnesium and the surface of the product particles is prone to moisture absorption, recrystallization, discoloration, uneven color, instability and product agglomeration. aspects of the problem

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