Ammonium phosphate drum granulation system based on multi-tube reaction

Abstract

The invention relates to chemical fertilizer production, and provides a multi-tube reaction-based ammonium phosphate drum granulation system, which comprises a granulator, a pre-neutralization tank and a tube reaction tank, the granulator is internally provided with an ammonia distributor, and a tube reactor A, a tube reactor B and a tube reactor C which are arranged below the ammonia distributor; the A pipe reactor and the B pipe reactor are both connected with a pipe reactor tank, and the pipe reactor tank is connected with a phosphoric acid cleaning agent; the C pipe reactor is connected with a pre-neutralization tank, the pre-neutralization tank is connected with an acid source, and the acid source comprises raffinate acid or sludge acid. The ammonium phosphate rotary drum granulation system based on the multi-tube reactor can effectively consume raffinate acid and sludge acid to produce DAP products.

Description

Technical Field

[0001] The invention relates to the technical field of fertilizer production, and in particular to a phosphate ammonium drum granulation system based on a multi-tube reaction. Background Art

[0002] Raffinate acid refers to the raffinate acid produced by purifying wet-process phosphoric acid to obtain industrial-grade phosphoric acid and food-grade phosphoric acid. Slag acid is a product formed during the production of wet-process phosphoric acid. Wet-process phosphoric acid is produced by decomposing phosphate rock with sulfuric acid, filtering and concentrating it. Since phosphate rock itself contains a large amount of metal impurities, during the concentration process, as the concentration of phosphoric acid increases, the solubility of impurity ions decreases, the supersaturation increases, and crystals precipitate to form slag acid.

[0003] DAP is a fertilizer containing nitrogen and phosphorus. The main components of DAP are nitrogen (N) and phosphorus (P), which provide these two key nutrients to plants to promote growth and development. 57% DAP and 64% DAP mainly refer to the percentage of nitrogen content.

[0004] The granulator can be used to add raffinate and slag acid in the process of producing DAP, which can replace part of the sulfuric acid and produce low-nutrition products. However, although adding slag acid directly to the tube reactor can reduce the consumption of sulfuric acid, the moisture content in the product is significantly increased. Adding raffinate acid directly to the tube reactor will cause serious system blockage (when the solid content in the raffinate acid is high, the fluidity of the washing liquid deteriorates, and the delivery pipeline and pump are blocked). Therefore, it is necessary to design a special production system for the application of raffinate and slag acid in DAP. Summary of the invention

[0005] The object of the present invention is to provide a phosphate ammonium drum granulation system based on a multi-tube reactor, which can effectively consume raffinate acid and slag acid to produce DAP products.

[0006] The present invention is achieved through the following technical scheme: the phosphate ammonium rotary drum granulation system based on multi-tube reactor of the present invention comprises a granulator, a pre-neutralization tank, and a tube reactor tank; an ammonia distributor is arranged in the granulator, and an A tube reactor, a B tube reactor, and a C tube reactor are arranged below the ammonia distributor; the A tube reactor and the B tube reactor are both connected to the tube reactor tank, and the tube reactor tank is connected to phosphoric acid purifying acid; the C tube reactor is connected to the pre-neutralization tank, and the pre-neutralization tank is connected to an acid source, and the acid source includes raffinate acid or slag acid.

[0007] Furthermore, the spraying volume of the A tube and the B tube is 30-40m 3 / h, the spraying volume of the C tube is 8-15m 3 / h.

[0008] Furthermore, the diameters of the A tube and the B tube are both 130-135 mm, and the wall thicknesses are both 8-10 mm.

[0009] Furthermore, the diameter of the C tube is 85-90 mm and the wall thickness is 8-10 mm.

[0010] Furthermore, the solid content of the phosphoric acid is less than 2%, the solid content of the slag acid is greater than 22%, and the content of P2O5 in the raffinate acid is 40-45%.

[0011] Furthermore, the pipe return tank is connected to a pre-wash tower washing liquid.

[0012] Furthermore, the pre-neutralization tank is connected to washing liquid and tail washing water.

[0013] Furthermore, a tube reaction pump is provided between the C tube reaction and the pre-neutralization tank, and the inlet of the tube reaction pump is connected with the pre-wash tower washing liquid.

[0014] The technical solution of the present invention has at least the following advantages and beneficial effects: the ammonium phosphate rotary drum granulation system based on the multi-tube reactor of the present invention adds a C tube reactor on the basis of the original A tube reactor and B tube reactor of the granulator, and the chemical by-product raffinate acid or slag acid is sprayed into the granulator through the C tube reactor for granulation, and the product granules have excellent properties and the product appearance quality is improved. By adding the C tube reactor, a low-nutrient DAP (diammonium hydrogen phosphate) product can be produced, which can replace the traditional method of adding sulfuric acid to adjust the excess nutrients of the product and add a new adjustment means, while reducing sulfuric acid consumption and production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0016] Figure 1 A schematic structural diagram of a phosphate ammonium drum granulation system based on a multi-tube reactor provided in an embodiment of the present invention.

[0017] Icons: 11-pre-neutralization tank, 12-acid source, 13-washing liquid, 14-tail wash water, 15-pre-wash tower washing liquid, 16-C tube reaction, 21-tube reaction tank, 22-phosphoric acid clearing acid, 23-A tube reaction, 24-B tube reaction. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0019] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0021] In the description of the present invention, it should be noted that if the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the product of the application is usually placed when used. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0022] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0023] Example 1

[0024] The following is further described in conjunction with specific embodiments. Figure 1As shown, this embodiment provides a phosphate ammonium drum granulation system based on a multi-tube reactor, including a granulator, a pre-neutralization tank 11, and a tube reactor tank 21; an ammonia distributor is provided in the granulator, and an A tube reactor 23, a B tube reactor 24, and a C tube reactor 16 are arranged below the ammonia distributor; the A tube reactor 23 and the B tube reactor 24 are both connected to the tube reactor tank 21, and the tube reactor tank 21 is connected to phosphoric acid 22; the C tube reactor 16 is connected to the pre-neutralization tank 11, and the pre-neutralization tank 11 is connected to the acid source 12, and the acid source 12 includes slag acid. Specifically, the C tube reactor 16 uses high-solid slag acid to produce low-nutrient granule core products to replace sulfuric acid and phosphogypsum to adjust the N content and rich nutrients in the product.

[0025] In this embodiment, the spraying amount of the A tube reactor 23 and the B tube reactor 24 is 30-40m3 / h, and the spraying amount of the C tube reactor 16 is 8-15m3 / h. The diameters of the A tube reactor 23 and the B tube reactor 24 are 130-135mm, and the wall thicknesses are 8-10mm. The diameter of the C tube reactor 16 is 85-90mm, and the wall thickness is 8-10mm. Specifically, by setting the relevant parameters of the A tube reactor 23, the B tube reactor 24 and the C tube reactor 16, the relative content of the clear acid and the slag acid can be adjusted to produce products with different nutrient contents.

[0026] The solid content of the phosphoric acid 22 in this embodiment is less than 2%, the solid content of the slag acid is greater than 22%, and the content of P2O5 in the raffinate acid is 40-45%.

[0027] The tube tank 21 in this embodiment is connected with the pre-wash tower washing liquid 15. Specifically, the pre-wash tower washing liquid 15 is mainly used to adjust the clear acid.

[0028] The pre-neutralization tank 11 in this embodiment is connected with a washing liquid 13 and a tail washing water 14. Specifically, the washing liquid 13 and the tail washing water 14 are mainly used to adjust and dilute the slag acid.

[0029] In this embodiment, a tube reaction pump is provided between the C tube reaction 16 and the pre-neutralization tank 11, and the inlet of the tube reaction pump is connected to the pre-wash tower washing liquid 15. Specifically, in order to prevent the increase of ammonia gas escaping from the granulator after the C tube reaction 16 is put into use, resulting in an increase in the N / P of the washing liquid 13 in the pre-wash tower, part of the pre-wash liquid 13 is added to the inlet of the C tube reaction 16 pump to balance the neutralization degree of the washing liquid 13 in the pre-wash tower.

[0030] Example 2

[0031] This embodiment provides a phosphate ammonium drum granulation system based on a multi-tube reactor, which is different from Example 1 in that the slag acid in Example 1 is replaced by raffinate acid.

[0032] For example, if a 600kt / a ammonium phosphate plant is used to produce DAP products with a total nutrient content of 53% or a series of products with added trace elements such as S and Zn, with an annual production of approximately 190,000 tons and a phosphoric acid consumption of 0.405t / t, and 10% of raffinate acid added to the ammonium phosphate acid used to produce the product, then: 19×0.405×10%=7,700 tons, that is, 7,700 tons of raffinate acid can be digested annually.

[0033] For example, if a 600kt / a ammonium phosphate plant is used to produce DAP products with a total nutrient content of 64% or a series of products with added trace elements such as S and Zn, with an annual production of approximately 670,000 tons and a phosphoric acid consumption of 0.475t / t, and 3% raffinate acid is added to the ammonium phosphate acid used to produce the product, then: 67×0.475×3%=9,700 tons, that is, 9,500 tons of raffinate acid can be digested annually.

[0034] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A phosphate ammonium drum granulation system based on a multi-tube reactor, characterized in that: It includes a granulator, a pre-neutralization tank, and a tube reaction tank; The granulator is provided with an ammonia distributor, and an A tube reactor, a B tube reactor, and a C tube reactor are arranged below the ammonia distributor; The A tube reactor and the B tube reactor are both connected to the tube reactor tank, and the tube reactor tank is connected to phosphoric acid; The C tube reaction is connected to the pre-neutralization tank, and the pre-neutralization tank is connected to an acid source, and the acid source includes raffinate acid or slag acid.

2. The phosphate ammonium rotary drum granulation system based on multi-tube reactor according to claim 1 is characterized in that: The spraying volume of the A tube and the B tube is 30-40m 3 / h, the spraying volume of the C tube is 8-15m 3 / h.

3. The phosphate ammonium rotary drum granulation system based on multi-tube reactor according to claim 1 is characterized in that: The diameters of the A tube and the B tube are both 130-135 mm, and the wall thicknesses are both 8-10 mm.

4. The phosphate ammonium rotary drum granulation system based on multi-tube reactor according to claim 1 is characterized in that: The C tube has a diameter of 85-90 mm and a wall thickness of 8-10 mm.

5. The phosphate ammonium rotary drum granulation system based on multi-tube reactor according to claim 1 is characterized in that: The solid content of the phosphoric acid is less than 2%, the solid content of the slag acid is greater than 22%, and the content of P2O5 in the raffinate acid is 40-45%.

6. The phosphate ammonium rotary drum granulation system based on multi-tube reactor according to claim 1 is characterized in that: The pipe return tank is connected with a pre-wash tower washing liquid.

7. The phosphate ammonium rotary drum granulation system based on multi-tube reactor according to claim 1 is characterized in that: The pre-neutralization tank is connected with washing liquid and tail washing water.

8. The phosphate ammonium rotary drum granulation system based on multi-tube reactor according to claim 1 is characterized in that: A tube reaction pump is provided between the C tube reaction and the pre-neutralization tank, and the inlet of the tube reaction pump is connected with the pre-wash tower washing liquid.

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