Scale dissolving agent for rapidly dissolving wet-process phosphoric acid scaling substances as well as preparation method and application of scale dissolving agent

Abstract

The invention discloses a scale dissolving agent for rapidly dissolving wet-process phosphoric acid scaling substances as well as a preparation method and application of the scale dissolving agent, and belongs to the technical field of descaling. The scale dissolving agent comprises the following components in percentage by weight: 20-30% of a scale remover, 3-5% of a penetrating agent, 0.3-0.8% of a penetrating aid, 0.5-1% of a surfactant, 0.3-0.5% of a synergist and the balance of water, wherein the descaling agent comprises trisodium citrate dehydrate, sodium ethylene diamine tetracetate and ammonium fluoride; the penetrating agent is prepared from dioctyl sodium sulfosuccinate and perfluoroalkyl ethyl acrylate; the permeation auxiliary agent comprises disodium hydrogen phosphate and sodium carbonate; and the synergist is 1-ethyl-3-methylimidazolium acetate. The scale dissolving agent is specially used for dissolving wet-process phosphoric acid scaling substances and has the advantages of being high in scale dissolving speed, mild in reaction condition, low in formula cost and the like, the pH value of the scale dissolving agent is neutral and slightly alkalescent, and corrosion to production equipment is effectively avoided.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of scale removers, and particularly relates to a scale remover for rapidly dissolving scale of wet-process phosphoric acid, a preparation method and application thereof. BACKGROUND

[0002] In the production process of wet-process phosphoric acid, the solution in the pipeline has high mineralization and contains a small amount of particulate acid-insoluble substances. With the long-time operation of the production device, the temperature, pressure and pH value in the flow process change, scale grains in the solution are generated and adsorbed on the pipeline to gradually grow. These changes promote the development of the pipeline in a direction conducive to scaling, and scale is inevitably produced. Meanwhile, the unevenness and undulation of the pipeline further promote the deposition of the scale grains on the pipe wall, resulting in the reduction of the inner diameter of the pipeline, the reduction of the flow cross-sectional area and the reduction of the displacement, so that the pipeline is seriously scaled during operation, forming a blockage and affecting the normal production of wet-process phosphoric acid. The main components of the scale of wet-process phosphoric acid are calcium and magnesium salts and fluorosilicate. The scale can cause equipment blockage, increase production energy consumption, reduce product quality, and directly affect the continuity of production due to the complexity and high hardness of the scale components and the difficulty of cleaning.

[0003] The prior art such as CN 115571863A discloses a scale remover for wet-process phosphoric acid, a preparation method and application thereof, which is composed of aminosulfonate scale remover, polymer dispersant, sulfonated succinic acid penetrant, benzotriazole corrosion inhibitor and sodium dodecyl benzene sulfonate surfactant. The scale remover has a complex formula, high cost, and is acidic, which has certain corrosiveness to production equipment, and is difficult to popularize and apply in actual production.

[0004] Therefore, a safe, efficient and low-cost scale remover for wet-process phosphoric acid is needed. SUMMARY

[0005] The application aims to provide a scale remover for rapidly dissolving scale of wet-process phosphoric acid, which has the characteristics of safety, efficiency and low cost.

[0006] To achieve the above technical purpose, the technical solution adopted by the application is as follows: A scale remover for rapidly dissolving scale of wet-process phosphoric acid, comprising the following components in percentage by weight: scale remover 20-30%, penetrant 3-5%, penetration aid 0.3-0.8%, surfactant 0.5-1%, synergist 0.3-0.5%, and the balance being water.

[0007] Further, the scale remover is trisodium citrate dihydrate, sodium ethylenediaminetetraacetate and ammonium fluoride, and the mass ratio of the three is 3:10:1.

[0008] Further, the penetrating agent comprises sodium sulfosuccinic acid diisooctyl ester and perfluoroalkyl ethyl acrylate, and the mass ratio of the two is 1:1.

[0009] Further, the penetrating aid comprises disodium hydrogen phosphate and sodium carbonate, and the mass ratio of the two is 1:3.

[0010] Further, the surfactant is sodium dodecyl benzene sulfonate.

[0011] Further, the synergist is 1-ethyl-3-methyl imidazole acetate.

[0012] A preparation method of a scale dissolver for quickly dissolving scale of wet-process phosphoric acid, comprising the following steps: The scale dissolver for quickly dissolving scale of wet-process phosphoric acid is prepared by adding the scale remover, the penetrating agent, the penetrating aid, the surfactant and the synergist into water and mixing uniformly.

[0013] Further, the mixing is stirred at a temperature of 50-70 DEG C.

[0014] The application further provides application of the scale dissolver for quickly dissolving scale of wet-process phosphoric acid in dissolving scale of wet-process phosphoric acid production.

[0015] The application adopts trisodium citrate dihydrate, sodium ethylenediaminetetraacetate and ammonium fluoride as the scale remover to carry out complex reaction with metal ions in the scale and promote dissolution of the scale.

[0016] The penetrating agent comprises sodium sulfosuccinic acid diisooctyl ester and perfluoroalkyl ethyl acrylate, wherein the sodium sulfosuccinic acid diisooctyl ester has good permeability and can reduce surface tension, thereby promoting dissolution of the scale; the perfluoroalkyl ethyl acrylate has extremely low surface tension and strong permeability, can penetrate into the smallest pores and the inside of stubborn scale layers, open the channel for the chelating agent to act, and maintain stable activity in a harsh cleaning environment; the sodium sulfosuccinic acid diisooctyl ester and the perfluoroalkyl ethyl acrylate have synergistic effect, provide strong penetration capacity, increase reaction area and improve scale dissolving speed.

[0017] The penetrating aid comprises disodium hydrogen phosphate and sodium carbonate, wherein the sodium carbonate reacts with residual phosphoric acid in the scale, released carbon dioxide gas can loosen the dirt, under the mechanical force of circulating water, the scale is stripped from the inner wall of the equipment, the cleaning strength is strong and the cleaning efficiency is high, at the same time, the pH value of the reaction solution can be maintained in the range of slight alkaline, corrosion to the equipment is avoided; the disodium hydrogen phosphate provides buffering and dispersing effect.

[0018] The present application adds synergist 1-ethyl-3-methyl imidazole acetate, which can effectively destroy the electrostatic force between ions in scale layer and crystal structure, and can be used as a high-efficiency carrier of scale remover and surface activity to promote its enrichment in the interior of scale layer, and the unique solvation environment can inhibit the recrystallization deposition of dissolved ions.

[0019] Advantages The scale dissolving agent of the present application is compounded by using specific scale remover, penetrating agent, penetration aid, surfactant and synergist, and has neutral to weak alkaline, high safety to personnel and production equipment, small corrosion to wet-process phosphoric acid production equipment, no damage to production equipment, mild reaction conditions, high scale removal efficiency, and can quickly dissolve and remove calcium, magnesium salts and fluorosilicate scale in the production process of wet-process phosphoric acid. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The transmission electron micrograph of scale in the production of wet-process phosphoric acid. DETAILED DESCRIPTION

[0021] The technical solutions of the present application are further described below in combination with specific examples, but are not limited thereto.

[0022] Example 1 A scale dissolving agent for quickly dissolving scale in the production of wet-process phosphoric acid, comprising the following components in weight percentage: scale remover 20%, penetrating agent 3%, penetration aid 0.3%, surfactant 0.5%, synergist 0.3%, and the balance being water.

[0023] The scale remover is trisodium citrate dihydrate, sodium ethylenediaminetetraacetate and ammonium fluoride, and the mass ratio of the three is 3:10:1.

[0024] The penetrating agent comprises sodium sulfosuccinic acid diisooctyl ester and perfluoroalkyl ethyl acrylate, and the mass ratio of the two is 1:1.

[0025] The penetration aid comprises disodium hydrogen phosphate and sodium carbonate, and the mass ratio of the two is 1:3.

[0026] The surfactant is sodium dodecyl benzene sulfonate.

[0027] The synergist is 1-ethyl-3-methyl imidazole acetate.

[0028] A preparation method of a scale dissolving agent for quickly dissolving scale in the production of wet-process phosphoric acid, comprising the following steps: The scale dissolving agent for quickly dissolving scale in the production of wet-process phosphoric acid is obtained by adding scale remover, penetrating agent, penetration aid, surfactant and synergist to water, and stirring and mixing uniformly at 50℃.

[0029] Example 2 A scale dissolver for quickly dissolving scale of wet-process phosphoric acid, comprising the following components by weight percentage: scale remover 25%, penetrating agent 4%, penetration aid 0.5%, surfactant 0.8%, synergist 0.4%, and the balance being water.

[0030] The scale remover is trisodium citrate dihydrate, sodium ethylenediaminetetraacetate, and ammonium fluoride, in a mass ratio of 3:10:1.

[0031] The penetrating agent comprises sodium diisooctyl sulfosuccinate and perfluoroalkyl ethyl acrylate, in a mass ratio of 1:1.

[0032] The penetration aid comprises disodium hydrogen phosphate and sodium carbonate, in a mass ratio of 1:3.

[0033] The surfactant is sodium dodecylbenzenesulfonate.

[0034] The synergist is 1-ethyl-3-methylimidazole acetate.

[0035] A method for preparing a scale dissolver for quickly dissolving scale of wet-process phosphoric acid, comprising the following steps: Adding the scale remover, penetrating agent, penetration aid, surfactant, and synergist to water, and stirring to mix uniformly at a temperature of 60°C, to obtain the scale dissolver for quickly dissolving scale of wet-process phosphoric acid.

[0036] Example 3 A scale dissolver for quickly dissolving scale of wet-process phosphoric acid, comprising the following components by weight percentage: scale remover 30%, penetrating agent 5%, penetration aid 0.8%, surfactant 1%, synergist 0.5%, and the balance being water.

[0037] The scale remover is trisodium citrate dihydrate, sodium ethylenediaminetetraacetate, and ammonium fluoride, in a mass ratio of 3:10:1.

[0038] The penetrating agent comprises sodium diisooctyl sulfosuccinate and perfluoroalkyl ethyl acrylate, in a mass ratio of 1:1.

[0039] The penetration aid comprises disodium hydrogen phosphate and sodium carbonate, in a mass ratio of 1:3.

[0040] The surfactant is sodium dodecylbenzenesulfonate.

[0041] The synergist is 1-ethyl-3-methylimidazole acetate.

[0042] A method for preparing a scale dissolver for quickly dissolving scale of wet-process phosphoric acid, comprising the following steps: The scale remover is prepared by adding scale remover, penetrating agent, penetrating aid, surfactant and synergist into water, and stirring and mixing uniformly at 70℃.

[0043] Comparative Example 1 The scale remover for rapidly dissolving scale of wet-process phosphoric acid is prepared by adding scale remover, penetrating agent, penetrating aid, surfactant and synergist into water, and stirring and mixing uniformly at 70℃.

[0044] The scale remover is prepared by adding scale remover, penetrating agent, penetrating aid, surfactant and synergist into water, and stirring and mixing uniformly at 70℃.

[0045] The scale remover is prepared by adding scale remover, penetrating agent, penetrating aid, surfactant and synergist into water, and stirring and mixing uniformly at 70℃.

[0046] The scale remover is prepared by adding scale remover, penetrating agent, penetrating aid, surfactant and synergist into water, and stirring and mixing uniformly at 70℃.

[0047] The scale remover is prepared by adding scale remover, penetrating agent, penetrating aid, surfactant and synergist into water, and stirring and mixing uniformly at 70℃.

[0048] The scale remover for rapidly dissolving scale of wet-process phosphoric acid is prepared by adding scale remover, penetrating agent, penetrating aid, surfactant and synergist into water, and stirring and mixing uniformly at 70℃. The scale remover is prepared by adding scale remover, penetrating agent, penetrating aid, surfactant and synergist into water, and stirring and mixing uniformly at 70℃.

[0049] The scale remover is prepared by adding scale remover, penetrating agent, penetrating aid, surfactant and synergist into water, and stirring and mixing uniformly at 70℃.

[0050] Comparative Example 2 The scale remover for rapidly dissolving scale of wet-process phosphoric acid is prepared by adding scale remover, penetrating agent, penetrating aid, surfactant and synergist into water, and stirring and mixing uniformly at 70℃.

[0051] The scale remover is prepared by adding scale remover, penetrating agent, penetrating aid, surfactant and synergist into water, and stirring and mixing uniformly at 70℃.

[0052] The scale remover is prepared by adding scale remover, penetrating agent, penetrating aid, surfactant and synergist into water, and stirring and mixing uniformly at 70℃.

[0053] The scale remover is prepared by adding scale remover, penetrating agent, penetrating aid, surfactant and synergist into water, and stirring and mixing uniformly at 70℃.

[0054] The scale remover is prepared by adding scale remover, penetrating agent, penetrating aid, surfactant and synergist into water, and stirring and mixing uniformly at 70℃.

[0055] The scale remover is prepared by adding scale remover, penetrating agent, penetrating aid, surfactant and synergist into water, and stirring and mixing uniformly at 70℃. The scale remover is prepared by adding scale remover, penetrating agent, penetrating aid, surfactant and synergist into water, and stirring and mixing uniformly at 70℃.

[0056] A method for preparing a scale solvent that rapidly dissolves wet-process phosphoric acid scale includes the following steps: Add the descaling agent, penetrant, penetrant aid, surfactant, and synergist to the water, and stir and mix them evenly at 70°C to obtain a scale dissolving agent that rapidly dissolves wet-process phosphoric acid scale.

[0057] Compared with Example 3, this comparative example uses only perfluoroalkyl ethyl acrylate as the penetrant, while the other raw materials and steps are the same as in Example 3.

[0058] Comparative Example 3 A scale remover that rapidly dissolves wet-process phosphoric acid scale comprises the following components by weight percentage: 30% scale remover, 5% penetrant, 0.8% penetrant aid, 1% surfactant, 0.5% synergist, and the balance being water.

[0059] The descaling agent is trisodium citrate dihydrate, sodium ethylenediaminetetraacetate, and ammonium fluoride, with a mass ratio of 3:10:1.

[0060] The penetrant comprises sodium diisooctyl sulfosuccinate and perfluoroalkyl ethyl acrylate in a mass ratio of 1:1.

[0061] The permeation aid is disodium hydrogen phosphate.

[0062] The surfactant is sodium dodecylbenzenesulfonate.

[0063] The synergist is 1-ethyl-3-methylimidazolium acetate.

[0064] A method for preparing a scale solvent that rapidly dissolves wet-process phosphoric acid scale includes the following steps: Add the descaling agent, penetrant, penetrant aid, surfactant, and synergist to the water, and stir and mix them evenly at 70°C to obtain a scale dissolving agent that rapidly dissolves wet-process phosphoric acid scale.

[0065] Compared with Example 3, this comparative example uses the same raw materials and steps as Example 3, except that the permeation aid is only disodium hydrogen phosphate.

[0066] Comparative Example 4 A scale remover that rapidly dissolves wet-process phosphoric acid scale comprises the following components by weight percentage: 30% scale remover, 5% penetrant, 0.8% penetrant aid, 1% surfactant, 0.5% synergist, and the balance being water.

[0067] The descaling agent is trisodium citrate dihydrate, sodium ethylenediaminetetraacetate, and ammonium fluoride, with a mass ratio of 3:10:1.

[0068] The penetrant comprises sodium diisooctyl sulfosuccinate and perfluoroalkyl ethyl acrylate in a mass ratio of 1:1.

[0069] The permeation aid mentioned is sodium carbonate.

[0070] The surfactant is sodium dodecylbenzenesulfonate.

[0071] The synergist is 1-ethyl-3-methylimidazolium acetate.

[0072] A method for preparing a scale solvent that rapidly dissolves wet-process phosphoric acid scale includes the following steps: Add the descaling agent, penetrant, penetrant aid, surfactant, and synergist to the water, and stir and mix them evenly at 70°C to obtain a scale dissolving agent that rapidly dissolves wet-process phosphoric acid scale.

[0073] Compared with Example 3, this comparative example uses the same raw materials and steps as Example 3, except that the permeation aid is only sodium carbonate.

[0074] Comparative Example 5 A scale remover that rapidly dissolves wet-process phosphoric acid scale comprises the following components by weight percentage: 30% scale remover, 5% penetrant, 0.8% penetrant aid, 1% surfactant, 0.5% synergist, and the balance being water.

[0075] The descaling agent is trisodium citrate dihydrate, sodium ethylenediaminetetraacetate, and ammonium fluoride, with a mass ratio of 3:10:1.

[0076] The penetrant includes sodium diisooctyl sulfosuccinate.

[0077] The permeation aids include disodium hydrogen phosphate and sodium carbonate, with a mass ratio of 1:3.

[0078] The surfactant is sodium dodecylbenzenesulfonate.

[0079] The synergist is 1-ethyl-3-methylimidazolium acetate.

[0080] A method for preparing a scale solvent that rapidly dissolves wet-process phosphoric acid scale includes the following steps: Add the descaling agent, penetrant, penetrant aid, surfactant, and synergist to the water, and stir and mix them evenly at 70°C to obtain a scale dissolving agent that rapidly dissolves wet-process phosphoric acid scale.

[0081] Compared with Example 3, this comparative example uses the same raw materials and steps as Example 3, except that the penetrant is sodium diisooctyl sulfosuccinate.

[0082] Performance testing The scale-dissolving properties of the scale-dissolving agents prepared in Examples 1-3 and Comparative Examples 1-5 on scale generated by wet-process phosphoric acid were tested. Scale from a wet-process phosphoric acid pipeline of a phosphate chemical plant in Linyi, Shandong Province, was analyzed using a transmission electron microscope (TEM). Figure 1 It can be seen that the scale crystals are layered and the scale structure is relatively dense, and filling traces can also be observed. Scale was added to the phosphoric acid scale solvent at a mass ratio of 10:1. The scale was then statically soaked in a 70℃ constant temperature water bath, and the dissolution rate of the scale was tested at 0.5h, 1h, and 2h. The specific testing method is as follows: A certain mass of scale was weighed and marked as m0, placed in the scale solvent, and after the specified time, the scale was washed three times with distilled water and dried to constant weight, with the mass marked as m1. The dissolution rate of the scale was W = (m0-m1) / m1 × 100%. The test results are shown in Table 1.

[0083] Table 1 Solubility of scale in each treatment group As can be seen from the test results in Table 1, the wet-process phosphoric acid scale removers prepared in each embodiment of the present invention have a high dissolution rate for scale. The dissolution rate is greater than 50% at 0.5 h and greater than 76% at 2 h. Among the three embodiments, Example 3 has the best effect, with a dissolution rate of over 85% at 2 h. According to the test results of Comparative Examples 2 and 5, when the total amount of penetrant remains constant, the absence of one component prevents the components in the penetrant from exerting a synergistic effect, resulting in a significant decrease in the scale-dissolving effect of the scale remover. Comparative Example 1 shows that the scale-dissolving rate of the scale remover also decreases significantly in the absence of the synergist. The results of Comparative Examples 3 and 4 also show that there is a synergistic effect between disodium hydrogen phosphate and sodium carbonate; the absence of either component also reduces the dissolution rate of the scale remover to varying degrees.

[0084] It should be noted that the above embodiments are merely some preferred embodiments of the present invention, and not all embodiments. Obviously, based on the above embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

Claims

1. A scale dissolver for rapidly dissolving a phosphoric acid scale formed by a wet process, characterized by comprising: The composition comprises the following components by weight percentage: scale remover 20-30%, penetrating agent 3-5%, penetration aid 0.3-0.8%, surfactant 0.5-1%, synergist 0.3-0.5%, and the balance being water.

2. The scale dissolver for fast dissolving wet process phosphoric acid scale according to claim 1, characterized in that, The scale remover is trisodium citrate dihydrate, sodium ethylenediaminetetraacetate, and ammonium fluoride, and the mass ratio of the three is 3:10:

1.

3. The scale dissolver for fast dissolving wet process phosphoric acid scale according to claim 1, characterized in that, The penetrating agent comprises sodium diisooctyl sulfosuccinate and perfluoroalkyl ethyl acrylate, and the mass ratio of the two is 1:

1.

4. The scale dissolver for fast dissolving wet process phosphoric acid scale according to claim 1, characterized in that, The penetration aid comprises disodium hydrogen phosphate and sodium carbonate, and the mass ratio of the two is 1:

3.

5. The scale dissolver for fast dissolving wet phosphoric acid scale according to claim 1, characterized in that, The surfactant is sodium dodecyl benzene sulfonate.

6. The scale dissolver for fast dissolving wet process phosphoric acid scale according to claim 1, characterized in that, The synergist is 1-ethyl-3-methyl imidazole acetate.

7. A process for the preparation of a scale dissolver for fast dissolving wet-process phosphoric acid scale according to any one of claims 1 to 6, characterized in that, The method comprises the following steps: The scale remover, penetrating agent, penetration aid, surfactant, and synergist are added to water, and the mixture is uniformly mixed to obtain the scale remover for rapidly dissolving wet-process phosphoric acid scale.

8. The method of claim 7, wherein the scale dissolver for fast dissolving wet phosphoric acid scale is prepared by, The mixing is stirred at a temperature of 50-70℃.

9. Use of the scale remover for rapidly dissolving wet-process phosphoric acid scale according to any one of claims 1-6 in cleaning of a wet-process phosphoric acid production device.

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