CN106831053A - A kind of production method of graininess, function intensified type phosphorus containing magnesium ammonium - Google Patents

Abstract

The invention discloses a production method of granular and function-enhanced magnesium-containing ammonium phosphate. Take 5%-50% of the total amount of phosphoric acid required for the production of ammonium phosphate, add bitter soil to react, and pass the resultant into liquid ammonia to neutralize to obtain a reaction slurry containing magnesium ammonium phosphate and ammonium phosphate; the remaining 95-50% of phosphoric acid is The original process produces ammonium phosphate granules, the above reaction slurry is sent to the tail of the granulator, sprayed and wrapped on the surface of ammonium phosphate granules, and then dried, screened, and cooled to obtain magnesium-containing ammonium phosphate products. This method adds magnesium, an important medium element, to traditional ammonium phosphate products. Magnesium and phosphorus have an important synergistic effect, which can significantly promote the absorption of phosphorus by crops, improve the fertilizer efficiency and utilization rate of phosphorus fertilizer, and improve crop quality. At the same time, the method can effectively prevent the ammonium phosphate product from absorbing moisture, decomposing, and recrystallizing, and has anti-dust and anti-caking effects similar to wrapped oil, and has a certain slow-release effect. The invention has the advantages of simple process, practicality, high efficiency, good product quality, good economic benefit, friendly environment and good application prospect.

Description

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

technical field

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

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 fertilizers.

A single magnesium ammonium phosphate product contains phosphorus, nitrogen and magnesium at the same time, which has certain advantages in this respect; but it is insoluble in water and is a slow-acting fertilizer soluble in citrate. It cannot quickly play the role of chemical fertilizer when applied alone, and generally can only be used as a fertilizer. The application of base fertilizer cannot be used as top dressing. Therefore, this product is a non-mainstream product in fertilizers at home and abroad, and its production and use are very small.

At present, the main production methods of magnesium ammonium phosphate at home and abroad are: (1) direct synthesis method: wet-process phosphoric acid is added with magnesium oxide, and then neutralized with ammonia to obtain precipitation of magnesium ammonium phosphate, liquid-solid separation, drying, and powdery crystals Product; (2) High-magnesium phosphate rock chemical purification method to remove magnesium by-product method: After the high-magnesium phosphate rock is ground, add a certain ratio of phosphoric acid or a mixed acid of phosphoric acid and sulfuric acid, and dissolve the magnesium in the phosphate rock through a chemical reaction. Carry out liquid-solid separation to obtain demagnesium-purified phosphate ore. The liquid phase contains soluble magnesium dihydrogen phosphate and magnesium sulfate, and then the liquid phase is neutralized by adding ammonia to precipitate magnesium ammonium phosphate. Perform liquid-solid separation and dry to obtain powdery crystals Product; (3) The method of removing ammonium nitrogen sewage by-products: in the sewage containing phosphate and ammonium nitrogen, add an appropriate amount or excessive magnesium ions, precipitate magnesium ammonium phosphate, carry out liquid-solid separation, dry, and obtain powdery crystalline products . Above three kinds of preparation methods of magnesium ammonium phosphate all can only obtain single powdery crystalline magnesium ammonium phosphate product, and its defect has been mentioned before. And the direct synthesis method, the procedure is loaded down with trivial details, and the water-soluble phosphorus of higher price is converted into the citric acid soluble phosphorus of low price, is not economical enough; By-product method produces magnesium ammonium phosphate product, has product concentration low, crystallization is fine, and product quality is not stable And other issues. Moreover, single magnesium ammonium phosphate is rarely produced and used as a fertilizer.

Although ammonium phosphate products (including monoammonium phosphate and diammonium phosphate, the same below) are phosphorus compound fertilizers, they contain high phosphorus (mainly water-soluble available phosphorus) and low nitrogen content, so they are mainly used for crop growth. required phosphorus. The production capacity of ammonium phosphate plant in my country has reached about 30 million tons, which is a kind of high-concentration phosphorus compound fertilizer with the largest production capacity and usage quantity. 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. 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.

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. In view of these deficiencies, it has become an important problem to be solved urgently to find an economical, reasonable and technically feasible production method of granular magnesium-containing ammonium phosphate to meet the market demand of products in terms of function enhancement and quality improvement.

Contents of the invention

The purpose of the present invention is to aim at the deficiencies in the production technology and product quality of the existing granular ammonium phosphate products, to provide a kind of wet-process phosphoric acid, liquid ammonia and bitter soil as the main raw materials, and to use the existing ammonium phosphate production equipment to prepare functionally enhanced The new granular magnesium-containing ammonium phosphate product method can significantly improve the quality, fertilizer efficiency and performance of ammonium phosphate products.

The purpose of the present invention is achieved through the following technical solutions.

Unless otherwise specified, the percentages used in the present invention are all mass percentages.

A method for producing granular, functionally enhanced magnesium-containing ammonium phosphate, comprising the following steps:

(1) Send phosphoric acid with a ratio of _5-50 % (calculated as pure _P2O5 , the same below) of the total amount of phosphoric acid used in the production of ammonium phosphate to the newly added reaction tank, add bitter soil and stir to mix evenly , the amount of bitter soil added is: the content of pure magnesium oxide in bitter soil accounts for 5% to 90% of the theoretical amount of magnesium oxide required to completely generate magnesium ammonium phosphate. , to obtain reactant A containing magnesium dihydrogen phosphate solution.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production plant, feeds liquid ammonia, and is neutralized in the ammonium phosphate production process, the normal neutralization degree (neutralization degree) controlled during pre-neutralization That is, the molar ratio of nitrogen and phosphorus, the same below. The monoammonium phosphate is about 0.90-1.20:1, and the diammonium phosphate is about 1.40-1.60:1), thus preparing the reaction slurry B containing the mixture of magnesium ammonium phosphate and ammonium phosphate.

(3) The remaining 95-50% phosphoric acid (calculated as pure P ₂ O ₅ , the same below) in the total amount of phosphoric acid produced by ammonium phosphate is sent to the tubular reactor according to the original production process, and the liquid is fed into it. Ammonia, neutralized to the normal control neutralization degree of the tubular reactor in the production process of ammonium phosphate (about 0.90-1.20:1 for monoammonium phosphate, about 1.40-1.60:1 for diammonium phosphate), to obtain neutralized slurry, and then According to the existing production process, the neutralized slurry is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the granulator, spray the slurry through multiple groups of nozzles set within 0.5-4.0m from the outlet end of the granulator, and spray the reaction slurry B on the surface after the above steps (3) The surface of the ammonium phosphate particles that have been granulated is subjected to surface spray coating and wrapping treatment, and then the granulation production is carried out according to the existing method.

When producing diammonium phosphate, liquid ammonia is further sprayed in the granulator for ammoniation, and the neutralization degree of the diammonium phosphate product is controlled to be 1.70-2.10:1.

(5) The discharge of the granulator, according to the original production process, method and control conditions, through drying, screening, cooling, metering and packaging to obtain granular, functionally enhanced magnesium-containing ammonium phosphate products.

Preferred production process and control conditions are:

(1) Send phosphoric acid with a ratio of 10-35% of the total amount of phosphoric acid used in the production of ammonium phosphate ₍ calculated as pure _P2O5 , the same below) to the newly added reaction tank, add bitter soil and stir to mix evenly , the amount of bitter soil added is: the content of pure magnesium oxide in bitter soil accounts for 15% to 40% of the theoretical amount of magnesium oxide required to completely generate magnesium ammonium phosphate, control the reaction temperature at 40-70 °C, and stir the reaction for 20-60 minutes , to obtain reactant A containing magnesium dihydrogen phosphate solution.

(2) Reactant A is sent into the existing, idle pre-neutralization tank of the ammonium phosphate production plant, feeds liquid ammonia, and is neutralized in the ammonium phosphate production process, the normal neutralization degree (middle) of control during pre-neutralization Harmony is the molar ratio of nitrogen and phosphorus, monoammonium phosphate is about 0.95-1.10:1, and diammonium phosphate is about 1.40-1.60:1), thus preparing reaction slurry B containing a mixture of magnesium ammonium phosphate and ammonium phosphate.

(3) The remaining 90-65% phosphoric acid of the total amount of phosphoric acid produced by ammonium phosphate is sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation .

(4) Send the reaction slurry B prepared in step (2) to the multiple groups of nozzles set within the range of 0.5-3.0m from the outlet end of the tail of the granulator for spraying, spraying after the above steps (3) , The surface of the granulated ammonium phosphate particles is subjected to surface spray coating and wrapping treatment, and then the granulation production is carried out according to the existing method.

When producing diammonium phosphate, liquid ammonia is further sprayed in the granulator for ammoniation, and the neutralization degree of the diammonium phosphate product is controlled to be 1.80-1.95:1.

(5) The discharge of the granulator, according to the original production process, method and control conditions, through drying, screening, cooling, metering and packaging to obtain granular, functionally enhanced magnesium-containing ammonium phosphate products.

Wherein, the raw material bitter soil used has a magnesium oxide content of 40-95%. The prepared reaction slurry B containing magnesium ammonium phosphate and ammonium phosphate mixture is also applicable to the production of granular compound fertilizer and compound fertilizer products by using ammonium phosphate device or using compound fertilizer and compound fertilizer device. Spray coating, wrapping treatment, production of function-enhanced granular compound fertilizer and compound fertilizer products. A new neutralization tank can be added separately to replace the existing pre-neutralization tank of the ammonium phosphate production unit. The existing wrapping barrel of the ammonium phosphate production device can be used or a new wrapping barrel can be added separately, and the above-mentioned reaction slurry B can be sent to the wrapping barrel for spraying, and the surface of the product particles can be coated and wrapped.

Compared with the prior art, the present invention has the following advantages:

(1) Utilize the existing ammonium phosphate production process and device to prepare a mixed slurry containing magnesium ammonium phosphate and ammonium phosphate (containing monoammonium phosphate, diammonium phosphate, the same below), and granulate the phosphorus at the tail of the granulator Ammonium particles are surface coated and wrapped. First, use the cohesiveness of the ammonium phosphate slurry contained in the ammonium phosphate mixed slurry to firmly adhere the insoluble magnesium ammonium phosphate powder (precipitation) to the granulated ammonium phosphate product particles Surface; Second, after coating and wrapping treatment of mixed slurry containing insoluble magnesium ammonium phosphate powder, the moisture absorption and solubility of the surface of ammonium phosphate product particles are significantly reduced, which can effectively prevent the surface of product particles from absorbing moisture and recrystallization , resulting in product discoloration, uneven color, instability, and product agglomeration and other appearance quality problems; it can also significantly reduce the dust generated by the product due to surface moisture absorption, dissolution, and recrystallization ("long hair"), and improve product packaging, storage and transportation. , application and other aspects of dust pollution problems; third, by adjusting the amount (ratio) of bitter soil to conveniently realize the control of ammonium phosphate product nitrogen, phosphorus, total nutrients and water-soluble phosphorus in the ratio of available phosphorus; fourth, in In the traditional ammonium phosphate production process and products, the addition of magnesium, an important medium element required for crop growth, has been well realized. Magnesium and phosphorus have a strong synergistic effect. Magnesium can significantly promote the photosynthesis of crops, and promote crops to Phosphorus absorption and utilization, thereby improving the phosphorus utilization rate of ammonium phosphate products (high phosphorus content), and at the same time improving crop quality; fifth, after coating the mixed slurry containing insoluble magnesium ammonium phosphate powder, After the package treatment, the ammonium phosphate product has a certain slow-release function, which can slow down the release rate of nutrients, improve fertilizer utilization rate and fertilizer efficiency, reduce fertilizer usage, increase production and income, increase the output-input ratio of growers, and increase economic benefits .

(2) The mixed slurry of magnesium ammonium phosphate and ammonium phosphate is used to replace the currently widely used wrapping oil for surface coating and wrapping treatment of ammonium phosphate products. The ammonium phosphate products produced are environmentally friendly products, which can reduce the chemical pollution of oil products. Oxygen consumption (COD), heavy metals and other pollution to the soil, realize green fertilization and green planting, with remarkable environmental benefits and ecological effects.

(3) Most ammonium phosphate production enterprises used to use "tubular reactor + pre-neutralization", that is, a mixed process to produce ammonium phosphate products. Through continuous development and technological transformation, at present, only tubular reactors are generally used for production , so that the pre-neutralization reaction tank system is idle, so using the traditional ammonium phosphate production device, the technology of the present invention is used to produce granular, functionally enhanced magnesium-containing ammonium phosphate products. Transformation, use of idle equipment, and basically no increase in investment, can realize production and achieve the purpose of product quality improvement, function strengthening and upgrading.

(4) The process of the present invention is simple and practical, the raw material is cheap, the production cost is low, and the economic and environmental benefits are remarkable.

Description of drawings

Fig. 1 is the pre-neutralization generally adopted in the prior art-the technological flow schematic diagram of tubular reactor process production ammonium phosphate product; Among the figure, dotted line represents idle unused part.

Fig. 2 is a schematic process flow diagram of the method of the present invention.

detailed description

The present invention will be further described below in conjunction with the drawings and examples, but the drawings and examples are not intended to limit the technical solution of the present invention. All changes made based on the teaching of the present invention shall belong to the protection scope of the present invention.

Example 1

Preparation of granular, functionally enhanced magnesium-containing ammonium phosphate products, as shown in Figure 2.

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts ₍ calculated in terms of pure _P2O5 , the same below), and 20 parts are taken out and sent to the newly added reaction tank, and added to calculate by completely generating magnesium ammonium phosphate, The pure MgO accounting for 25% of the required theoretical amount is stirred and mixed evenly, the reaction temperature is controlled at 50° C., and the reactant A containing magnesium dihydrogen phosphate solution is obtained after 40 minutes of stirring reaction. In this embodiment, the MgO content of the actual bitter soil used is 75%, so the actual amount of the physical bitter soil added is 3.8 parts.

Calculation of the amount of bitter soil added: According to the chemical reaction formula of H ₃ PO ₄ completely reacting with MgO and NH ₃ to generate MgNH ₄ PO ₄ , it can be calculated that it is equivalent to 20 parts of phosphoric acid (based on pure P ₂ O ₅ ) In 27.6 parts of H ₃ PO ₄ ), the reaction is complete, and the theoretical amount of pure MgO required is 11.26 parts. In this embodiment 1, the amount of pure MgO actually added only accounts for 25% of the required theoretical amount, so the actual amount of pure MgO added is: 11.26╳25%=2.82 (parts), and the MgO of bitter soil is actually used The content is 75%, so the actual amount of bitter soil added is: 2.82÷75%=3.8 (parts).

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Monoammonium 1.08:1), thus preparing the reaction slurry B.

(3) The remaining 80 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). On the surface, the surface coating treatment is carried out, and according to the original production process, it is further neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: monoammonium phosphate 1.08:1).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 1.68% MgO.

Example 2

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts ₍ calculated in terms of pure _P2O5 , the same below), and 10 parts are taken out and sent to the newly added reaction tank, and added to calculate by completely generating magnesium ammonium phosphate, The pure MgO accounting for 15% of the required theoretical amount is stirred and mixed evenly, the reaction temperature is controlled at 40° C., and after 45 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 80%, so the actual amount of the physical bitter soil added is 1.1 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Monoammonium 1.05), thus preparing the reaction slurry B.

(3) The remaining 90 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment, according to the original production process, further neutralization to the normal control of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: monoammonium phosphate 1.05).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 0.56% MgO.

Example 3

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts ₍ calculated in terms of pure _P2O5 , the same below), and 10 parts are taken out and sent to the newly added reaction tank, and added to calculate by completely generating magnesium ammonium phosphate, The pure MgO accounting for 25% of the required theoretical amount is stirred and mixed evenly, the reaction temperature is controlled at 50° C., and after 60 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 85%, so the actual amount of the physical bitter soil added is 1.7 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Monoammonium 1.02), thus preparing the reaction slurry B.

(3) The remaining 90 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment, according to the original production process, further neutralization to the normal control of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: monoammonium phosphate 1.02).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 0.86% MgO.

Example 4

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts ₍ calculated in terms of pure _P2O5 , the same below), and 10 parts are taken out and sent to the newly added reaction tank, and added to calculate by completely generating magnesium ammonium phosphate, The pure MgO, which accounts for 40% of the required theoretical amount, is stirred and mixed evenly, and the reaction temperature is controlled at 60 ° C. After 80 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 90%, so the actual amount of the physical bitter soil added is 2.5 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Monoammonium 1.10), thus preparing the reaction slurry B.

(3) The remaining 90 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment is carried out on the surface, and according to the original production process, it is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: monoammonium phosphate 1.10).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 1.36% MgO.

Example 5

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts ₍ calculated as pure _P2O5 , the same below), and 35 parts are taken out and sent to the newly added reaction tank, and added to calculate by completely generating magnesium ammonium phosphate, The pure MgO which accounts for 25% of the required theoretical amount is stirred and mixed evenly, and the reaction temperature is controlled at 60°C. After 80 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 45%, so the actual amount of the physical bitter soil added is 11 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Monoammonium 1.10), thus preparing the reaction slurry B.

(3) The remaining 65 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment is carried out on the surface, and according to the original production process, it is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: monoammonium phosphate 1.10).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 2.81% MgO.

Example 6

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts ₍ calculated as pure _P2O5 , the same below), and 35 parts are taken out and sent to the newly added reaction tank, and added to calculate by completely generating magnesium ammonium phosphate, The pure MgO accounting for 40% of the required theoretical amount is stirred and mixed evenly, the reaction temperature is controlled at 65°C, and after 70 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 50%, so the actual amount of the physical bitter soil added is 16 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Monoammonium 1.08), thus preparing the reaction slurry B.

(3) The remaining 65 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment, according to the original production process, further neutralized to the normal control of ammonium phosphate production (neutralization degree is the nitrogen-phosphorus molar ratio: monoammonium phosphate 1.08),

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 4.33% MgO.

Example 7

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts ₍ calculated in terms of pure _P2O5 , the same below), and 20 parts are taken out and sent to the newly added reaction tank, and added to calculate by completely generating magnesium ammonium phosphate, The pure MgO accounting for 25% of the required theoretical amount is stirred and mixed evenly, the reaction temperature is controlled at 55° C., and after 45 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 55%, so the actual amount of the physical bitter soil added is 5.1 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Diammonium 1.41), thus preparing reaction slurry B.

(3) The remaining 80 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment is carried out on the surface, and according to the original production process, it is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: diammonium phosphate 1.88).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 1.47% MgO.

Example 8

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts ₍ calculated in terms of pure _P2O5 , the same below), and 10 parts are taken out and sent to the newly added reaction tank, and added to calculate by completely generating magnesium ammonium phosphate, The pure MgO accounting for 15% of the required theoretical amount is stirred and mixed evenly, the reaction temperature is controlled at 45° C., and after 45 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 60%, so the actual amount of the physical bitter soil added is 1.4 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Diammonium 1.45), thus preparing reaction slurry B.

(3) The remaining 90 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment is carried out on the surface, and according to the original production process, it is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: diammonium phosphate 1.88).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 0.45% MgO.

Example 9

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts ₍ calculated in terms of pure _P2O5 , the same below), and 10 parts are taken out and sent to the newly added reaction tank, and added to calculate by completely generating magnesium ammonium phosphate, The pure MgO accounting for 25% of the required theoretical amount is stirred and mixed evenly, the reaction temperature is controlled at 55° C., and after 60 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 65%, so the actual amount of the physical bitter soil added is 2.2 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Diammonium 1.43), thus preparing reaction slurry B.

(3) The remaining 90 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment, according to the original production process, further neutralized to the normal control of ammonium phosphate production (neutralization degree is the nitrogen-phosphorus molar ratio: diammonium phosphate 1.89),

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 0.75% MgO.

Example 10

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts ₍ calculated in terms of pure _P2O5 , the same below), and 10 parts are taken out and sent to the newly added reaction tank, and added to calculate by completely generating magnesium ammonium phosphate, The pure MgO which accounts for 40% of the required theoretical amount is stirred and mixed evenly, and the reaction temperature is controlled at 65°C. After 80 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 70%, so the actual amount of the physical bitter soil added is 3.2 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Diammonium 1.41), thus preparing reaction slurry B.

(3) The remaining 90 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment is carried out on the surface, and further neutralized to the normal control neutralization degree of ammonium phosphate production according to the original production process (neutralization degree is the molar ratio of nitrogen to phosphorus: diammonium phosphate 1.90).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 1.19% MgO.

Example 11

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts ₍ calculated as pure _P2O5 , the same below), and 35 parts are taken out and sent to the newly added reaction tank, and added to calculate by completely generating magnesium ammonium phosphate, The pure MgO which accounts for 25% of the required theoretical amount is stirred and mixed evenly, and the reaction temperature is controlled at 60°C. After 65 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 75%, so the actual amount of the physical bitter soil added is 6.6 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Diammonium 1.42), thus preparing reaction slurry B.

(3) The remaining 90 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment is carried out on the surface, and further neutralized to the normal control neutralization degree of ammonium phosphate production according to the original production process (neutralization degree is the molar ratio of nitrogen to phosphorus: diammonium phosphate 1.87).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 2.55% MgO.

Example 12

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts ₍ calculated as pure _P2O5 , the same below), and 35 parts are taken out and sent to the newly added reaction tank, and added to calculate by completely generating magnesium ammonium phosphate, The pure MgO accounting for 40% of the required theoretical amount is stirred and mixed evenly, the reaction temperature is controlled at 65°C, and after 70 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 80%, so the actual amount of the physical bitter soil added is 9.9 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Diammonium 1.48), thus preparing reaction slurry B.

(3) The remaining 65 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment, according to the original production process, neutralization to the normal control of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: diammonium phosphate 1.91).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 4.01% MgO.

Example 13

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts (calculated in terms of pure _P2O5 , the same below), and ₅ parts are taken out and sent to the newly added reaction tank, and added to calculate the complete generation of magnesium ammonium phosphate, The pure MgO which accounts for 5% of the required theoretical amount is stirred and mixed evenly, the reaction temperature is controlled at 30° C., and after 40 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 85%, so the actual amount of the physical bitter soil added is 0.2 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Monoammonium 0.98), thus preparing the reaction slurry B.

(3) The remaining 95 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment is carried out on the surface, and further neutralized to the normal control neutralization degree of ammonium phosphate production according to the original production process (neutralization degree is the molar ratio of nitrogen to phosphorus: monoammonium phosphate 0.98).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 0.09% MgO.

Example 14

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts (calculated in terms of pure _P2O5 , the same below), and ₅ parts are taken out and sent to the newly added reaction tank, and added to calculate the complete generation of magnesium ammonium phosphate, The pure MgO, which accounts for 25% of the required theoretical amount, is stirred and mixed evenly, and the reaction temperature is controlled at 40°C. After 50 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 90%, so the actual amount of the physical bitter soil added is 0.8 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Monoammonium 1.02), thus preparing the reaction slurry B.

(3) The remaining 95 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment, according to the original production process, further neutralization to the normal control of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: monoammonium phosphate 1.02).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 0.43% MgO.

Example 15

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts (calculated in terms of pure _P2O5 , the same below), and ₅ parts are taken out and sent to the newly added reaction tank, and added to calculate the complete generation of magnesium ammonium phosphate, The pure MgO, which accounts for 90% of the required theoretical amount, is stirred and mixed evenly, and the reaction temperature is controlled at 60°C. After 100 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 45%, so the actual amount of the physical bitter soil added is 5.63 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Monoammonium 1.18), thus preparing the reaction slurry B.

(3) The remaining 95 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment is carried out on the surface, and further neutralized to the normal control neutralization degree of ammonium phosphate production according to the original production process (neutralization degree is the molar ratio of nitrogen to phosphorus: monoammonium phosphate 1.18).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 1.5% MgO.

Example 16

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts ₍ calculated in terms of pure _P2O5 , the same below), and 20 parts are taken out and sent to the newly added reaction tank, and added to calculate by completely generating magnesium ammonium phosphate, The pure MgO which accounts for 5% of the required theoretical dosage is stirred and mixed evenly, the reaction temperature is controlled at 35°C, and after 30 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 50%, so the actual amount of the physical bitter soil added is 1.2 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Monoammonium 1.04), thus preparing the reaction slurry B.

(3) The remaining 80 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, spraying on the ammonium phosphate particles that have been granulated after the above step (3) Surface coating treatment is carried out on the surface, and according to the original production process, it is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: monoammonium phosphate 1.04).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 0.34% MgO.

Example 17

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts ₍ calculated in terms of pure _P2O5 , the same below), and 20 parts are taken out and sent to the newly added reaction tank, and added to calculate by completely generating magnesium ammonium phosphate, The pure MgO, which accounts for 90% of the required theoretical amount, is stirred and mixed evenly, and the reaction temperature is controlled at 65 ° C. After 90 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the used bitter soil is 55%, so the actual amount of bitter soil added is 18 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Monoammonium 1.06), thus preparing the reaction slurry B.

(3) The remaining 80 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment is carried out on the surface, and according to the original production process, it is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: monoammonium phosphate 1.06).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 5.45% MgO.

Example 18

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts (calculated as pure _P2O5 , the same below), and ₅₀ parts are taken out and sent to the newly added reaction tank, and added to calculate the complete generation of magnesium ammonium phosphate, The pure MgO accounting for 5% of the required theoretical amount is stirred and mixed evenly, the reaction temperature is controlled at 40° C., and after 30 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 60%, so the actual amount of the physical bitter soil added is 2.4 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Monoammonium 1.06), thus preparing the reaction slurry B.

(3) The remaining 50 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, spraying on the ammonium phosphate particles that have been granulated after the above step (3) Surface coating treatment is carried out on the surface, and according to the original production process, it is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: monoammonium phosphate 1.06).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 0.84% MgO.

Example 19

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts (calculated as pure _P2O5 , the same below), and ₅₀ parts are taken out and sent to the newly added reaction tank, and added to calculate the complete generation of magnesium ammonium phosphate, The pure MgO, which accounts for 25% of the required theoretical amount, is stirred and mixed evenly, and the reaction temperature is controlled at 55 ° C. After 55 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 65%, so the actual amount of the physical bitter soil added is 11 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Monoammonium 1.1), thus preparing the reaction slurry B.

(3) The remaining 50 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, spraying on the ammonium phosphate particles that have been granulated after the above step (3) Surface coating treatment is carried out on the surface, and according to the original production process, it is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: monoammonium phosphate 1.1).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 3.99% MgO.

Example 20

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts (calculated as pure _P2O5 , the same below), and ₅₀ parts are taken out and sent to the newly added reaction tank, and added to calculate the complete generation of magnesium ammonium phosphate, The pure MgO which accounts for 90% of the required theoretical amount is stirred and mixed evenly, the reaction temperature is controlled at 60° C., and after 60 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 65%, so the actual amount of the physical bitter soil added is 39 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Monoammonium 1.12), thus preparing the reaction slurry B.

(3) The remaining 50 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment is carried out on the surface, and according to the original production process, it is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: monoammonium phosphate 1.12).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 11.79% MgO.

Example 21

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts (calculated in terms of pure _P2O5 , the same below), and ₅ parts are taken out and sent to the newly added reaction tank, and added to calculate the complete generation of magnesium ammonium phosphate, The pure MgO accounting for 5% of the required theoretical dosage was stirred and mixed evenly, the reaction temperature was controlled at 35°C, and after 40 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution was obtained. In this embodiment, the MgO content of the actual bitter soil used is 70%, so the actual amount of the physical bitter soil added is 0.2 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Diammonium 1.51), thus preparing the reaction slurry B.

(3) The remaining 95 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment is carried out on the surface, and further neutralized to the normal control neutralization degree of ammonium phosphate production according to the original production process (neutralization degree is the molar ratio of nitrogen to phosphorus: diammonium phosphate 1.86).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 0.08% MgO.

Example 22

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts (calculated in terms of pure _P2O5 , the same below), and ₅ parts are taken out and sent to the newly added reaction tank, and added to calculate the complete generation of magnesium ammonium phosphate, The pure MgO accounting for 25% of the required theoretical amount is stirred and mixed evenly, the reaction temperature is controlled at 45°C, and after 50 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 75%, so the actual amount of the physical bitter soil added is 0.9 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Diammonium 1.52), thus preparing the reaction slurry B.

(3) The remaining 95 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment is carried out on the surface, and according to the original production process, it is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: diammonium phosphate 1.87).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 0.44% MgO.

Example 23

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts (calculated in terms of pure _P2O5 , the same below), and ₅ parts are taken out and sent to the newly added reaction tank, and added to calculate the complete generation of magnesium ammonium phosphate, The pure MgO, which accounts for 90% of the required theoretical amount, is stirred and mixed evenly, and the reaction temperature is controlled at 65 ° C. After 100 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 80%, so the actual amount of the physical bitter soil added is 3.2 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Diammonium 1.54), thus preparing reaction slurry B.

(3) The remaining 95 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment, according to the original production process, further neutralization to the normal control of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: diammonium phosphate 1.92).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 1.34% MgO.

Example 24

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts ₍ calculated in terms of pure _P2O5 , the same below), and 20 parts are taken out and sent to the newly added reaction tank, and added to calculate by completely generating magnesium ammonium phosphate, The pure MgO which accounts for 5% of the required theoretical dosage is stirred and mixed evenly, the reaction temperature is controlled at 40°C, and after 35 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 85%, so the actual amount of the physical bitter soil added is 0.7 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Diammonium 1.48), thus preparing reaction slurry B.

(3) The remaining 80 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment is carried out on the surface, and further neutralized to the normal control neutralization degree of ammonium phosphate production according to the original production process (neutralization degree is the molar ratio of nitrogen to phosphorus: diammonium phosphate 1.86).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 0.3% MgO.

Example 25

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts ₍ calculated in terms of pure _P2O5 , the same below), and 20 parts are taken out and sent to the newly added reaction tank, and added to calculate by completely generating magnesium ammonium phosphate, The pure MgO, which accounts for 90% of the required theoretical amount, is stirred and mixed evenly, and the reaction temperature is controlled at 70°C. After 90 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 85%, so the actual amount of the physical bitter soil added is 12 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Diammonium 1.51), thus preparing the reaction slurry B.

(3) The remaining 80 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment is carried out on the surface, and further neutralized to the normal control neutralization degree of ammonium phosphate production according to the original production process (neutralization degree is the molar ratio of nitrogen to phosphorus: diammonium phosphate 1.89).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 5.09% MgO.

Example 26

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts (calculated as pure _P2O5 , the same below), and ₅₀ parts are taken out and sent to the newly added reaction tank, and added to calculate the complete generation of magnesium ammonium phosphate, The pure MgO which accounts for 5% of the required theoretical dosage is stirred and mixed evenly, and the reaction temperature is controlled at 45°C. After 30 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 90%, so the actual amount of the physical bitter soil added is 1.6 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Diammonium 1.46), thus preparing reaction slurry B.

(3) The remaining 50 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment is carried out on the surface, and according to the original production process, it is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: diammonium phosphate 1.90).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 0.75% MgO.

Example 27

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts (calculated as pure _P2O5 , the same below), and ₅₀ parts are taken out and sent to the newly added reaction tank, and added to calculate the complete generation of magnesium ammonium phosphate, The pure MgO which accounts for 25% of the required theoretical amount is stirred and mixed evenly, and the reaction temperature is controlled at 60°C. After 55 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the actual bitter soil used is 65%, so the actual amount of the physical bitter soil added is 11 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Diammonium 1.50), thus preparing the reaction slurry B.

(3) The remaining 50 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, and spray on the ammonium phosphate particles that have been granulated after the above step (3). Surface coating treatment is carried out on the surface, and further neutralized to the normal control neutralization degree of ammonium phosphate production according to the original production process (neutralization degree is the molar ratio of nitrogen to phosphorus: diammonium phosphate 1.89).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 3.98% MgO.

Example 28

(1) The total amount of phosphoric acid used to produce ammonium phosphate products is 100 parts (calculated as pure _P2O5 , the same below), and ₅₀ parts are taken out and sent to the newly added reaction tank, and added to calculate the complete generation of magnesium ammonium phosphate, The pure MgO accounting for 90% of the required theoretical amount is stirred and mixed evenly, the reaction temperature is controlled at 65°C, and after 60 minutes of reaction, the reactant A containing magnesium dihydrogen phosphate solution is obtained. In this embodiment, the MgO content of the used bitter soil is 75%, so the actual amount of bitter soil added is 34 parts.

(2) Reactant A is sent into the existing pre-neutralization tank of the ammonium phosphate production unit, feeds liquid ammonia, and is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: phosphoric acid Diammonium 1.51), thus preparing the reaction slurry B.

(3) The remaining 50 parts of phosphoric acid are sent to the tubular reactor according to the conventional method, and liquid ammonia is introduced to obtain neutralized slurry, which is sent to the granulator for spray granulation.

(4) Send the reaction slurry B to the multiple groups of nozzles set within the range of 0.5-4.0m from the outlet end of the tail of the granulator for spraying, spraying on the ammonium phosphate particles that have been granulated after the above step (3) Surface coating treatment is carried out on the surface, and according to the original production process, it is neutralized to the normal control neutralization degree of ammonium phosphate production (neutralization degree is the molar ratio of nitrogen to phosphorus: diammonium phosphate 1.91).

(5) The discharge of the granulator, according to the original production process, is dried, cooled, sieved, measured and packaged to obtain a granular, functionally enhanced magnesium-containing ammonium phosphate product. In addition to containing corresponding N and P, the product also contains Contains 11.4% MgO.

Claims (7)

1. a kind of graininess, the production method of function intensified type phosphorus containing magnesium ammonium, it is characterised in that comprise the following steps：

(1) take 5%~50% of phosphoric acid total amount needed for production of ammonium phosphate to be sent in the reactive tank newly established, addition magnesia stirring mixing Uniformly, the addition of magnesia is：Pure content of magnesia accounts for the theoretical use of magnesia completely needed for generation ammonium magnesium phosphate in magnesia The 5%~90% of amount, 20~90 DEG C of controlling reaction temperature, by 10~120min stirring reactions, obtains containing magnesium dihydrogen phosphate Reactant A；

(2) by reactant A feeding production of ammonium phosphate device preneutralization groove in, be passed through liquefied ammonia neutralization, obtain containing ammonium magnesium phosphate with The reaction slurry B of phosphorus ammonium mixture；

(3) by phosphoric acid total amount needed for production of ammonium phosphate remaining 95~50% phosphoric acid, tubular type is sent into by the existing technological process of production In reactor, it is passed through the further ammonification of liquefied ammonia and neutralizes, and the slurry feeding comminutor become reconciled by carries out slurry-spraying pelletizing, obtains phosphorus Ammonium particle；

(4) multigroup shower nozzle is set in the range of the first 0.5~4.0m of the distance granulation drive end unit port of export, reaction slurry B is uniformly sprayed Apply, be wrapped in the phosphorus ammonium particle surface that step (3) is obtained；

(5) it is to obtain required to complete the granule materials drying after spraying parcel treatment, screening, cooling and metering packing Granular, function intensified type ammonium phosphate product containing magnesium.

2. graininess according to claim 1, the production method of function intensified type phosphorus containing magnesium ammonium, it is characterised in that：Control The nitrogen phosphorus mol ratio of step (2) described preneutralization, wherein being 0.90~1.20 during production MAP：1, during production Diammonium phosphate (DAP) It is 1.40~1.60：1；The nitrogen phosphorus mol ratio of rate-determining steps (3) described neutralization, wherein during production MAP for 0.90~ 1.20：1, it is 1.40~1.60 during production Diammonium phosphate (DAP)：1；Step (4), when Diammonium phosphate (DAP) is produced, the hydrojet ammonia in comminutor Further ammonia is neutralized, and the nitrogen phosphorus mol ratio for controlling diammonium phosphate product is 1.70~2.10：1.

3. graininess according to claim 1, the production method of function intensified type phosphorus containing magnesium ammonium, it is characterised in that：

In step (1), take 10%~35% of phosphoric acid total amount needed for production of ammonium phosphate and be sent in the reactive tank newly established, add magnesia It is uniformly mixed, the addition of magnesia is：Pure content of magnesia accounts for magnesia completely needed for generation ammonium magnesium phosphate in magnesia Theoretical amount 15%~40%, 40~70 DEG C of controlling reaction temperature, by 20~60min stirring reactions, obtains containing phosphorus The reactant A of acid dihydride magnesium；

In step (3), by phosphoric acid total amount needed for production of ammonium phosphate remaining 90%~65% phosphoric acid, by the existing technological process of production In feeding tubular reactor, liquefied ammonia neutralization is passed through, and the slurry feeding comminutor become reconciled by carries out slurry-spraying pelletizing, obtains phosphorus ammonium Particle；

In step (4), multigroup shower nozzle is set in the range of the first 0.5~3.0m of the distance granulation drive end unit port of export.

4. graininess according to claim 3, the production method of function intensified type phosphorus containing magnesium ammonium, it is characterised in that：Control The nitrogen phosphorus mol ratio of preneutralization described in step (2), wherein being 0.95~1.1 during production MAP：1, produce Diammonium phosphate (DAP) When be 1.42~1.52：1；The nitrogen phosphorus mol ratio neutralized described in rate-determining steps (3), wherein during production MAP for 0.95~ 1.1：1, it is 1.85~1.92 during production Diammonium phosphate (DAP)：1.

5. graininess according to claim 1, the production method of function intensified type phosphorus containing magnesium ammonium, it is characterised in that：Will step Suddenly the reaction slurry B containing ammonium magnesium phosphate and phosphorus ammonium mixture obtained by (2), for other granular complex fertilizers or granular multiple Complex fertilizer carries out surface spraying parcel treatment, so as to obtain function intensified type granular complex fertilizer, compound fertilizer product.

6. graininess according to claim 1 or 3, the production method of function intensified type phosphorus containing magnesium ammonium, it is characterised in that：Will Reaction slurry B introduces the existing parcel cylinder of production of ammonium phosphate device or sets up a new parcel cylinder, the phosphorus ammonium obtained to step (3) Particle carries out surface spraying parcel.

7. graininess according to claim 1 or 3, the production method of function intensified type phosphorus containing magnesium ammonium, it is characterised in that：Institute The content of magnesia for stating magnesia is 40~95%.