Environment-friendly anti-rust abrasive for water sand blasting and preparation method thereof

Abstract

This invention belongs to the field of green coating technology, specifically relating to an environmentally friendly rust-preventive abrasive for water blasting and its preparation method. The rust-preventive abrasive, by weight, comprises 80-90 parts white sugar, 5-10 parts sodium metal salt, 3-5 parts borate ester, and 2-5 parts sulfonate. The abrasive of this invention not only removes old paint or iron oxide scale from the surface of a metal substrate through high-speed impact, producing a certain degree of roughness, but also contains rust-preventive components, effectively solving the flash rust problem caused by water blasting. Furthermore, all components of the abrasive have high solubility in water, solving the abrasive recycling problem encountered after traditional water blasting processes.

Description

Technical Field

[0001] This invention belongs to the field of green coating technology, specifically relating to an environmentally friendly anti-rust abrasive for water jet sandblasting and its preparation method. Background Technology

[0002] Water blasting, with its advantages of being dust-free and spark-free during construction, has been widely applied on numerous land-based sites and offshore platforms, with a growing trend towards large-scale application. However, the surface of the iron substrate treated with this process is in a corrosion-activated zone due to the presence of water and oxygen, making it highly susceptible to flash rust. To avoid affecting the anti-corrosion performance of the coating, it often requires further grinding or roughening, which is labor-intensive, material-intensive, and affects the construction cycle. Furthermore, traditional water blasting processes present the challenge of recycling abrasive materials (such as copper ore sand and garnet) after completion, which to some extent limits the widespread adoption of this technology. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides an environmentally friendly rust-preventive abrasive for water blasting. This abrasive not only removes old paint or iron oxide scale from the surface of metal substrates through high-speed impact, creating a certain degree of roughness, but also contains rust-preventive components, effectively solving the flash rust problem caused by water blasting. Furthermore, all components of the abrasive have high solubility in water, solving the abrasive recycling problem encountered after traditional water blasting processes.

[0004] Abrasives are calculated by weight, including

[0005]

[0006] As a preferred option, the white sugar should be industrial grade, with a mesh size of 60-80 mesh.

[0007] Preferably, the sodium salt is one or a combination of sodium carbonate, sodium bicarbonate, sodium molybdate, sodium phosphate, and sodium gluconate.

[0008] Preferably, the borate ester is triethanolamine borate and / or diethanolamine borate.

[0009] Preferably, the sulfonate is one or a combination of several of water-soluble sodium petroleum sulfonate, water-soluble ammonium petroleum sulfonate, and water-soluble potassium petroleum sulfonate.

[0010] The present invention also provides a method for preparing the above-mentioned environmentally friendly anti-rust abrasive for water blasting: white sugar, sodium metal salt, borate ester, and sulfonate are added to a powder mixer and stirred until fully mixed.

[0011] Preferably, the stirring speed is 1 to 3 r / min.

[0012] As a preferred option, the stirring time is 30 to 60 minutes.

[0013] The beneficial effects of this invention are as follows:

[0014] This invention uses industrial-grade white sugar as the main abrasive. Industrial-grade white sugar is low in toxicity and environmentally friendly, making it suitable for sandblasting sites with strict requirements for waste discharge. Furthermore, industrial-grade white sugar has extremely high solubility in water, allowing it to dissolve rapidly and solving the abrasive recycling problem encountered after traditional water blasting processes. However, generally speaking, highly water-soluble granular materials dissolve rapidly in water, leading to a decrease in the actual number and volume of abrasive particles impacting the substrate during sandblasting, affecting the impact and abrasion effect on the substrate surface. The applicant discovered that white sugar, unlike other highly water-soluble granular materials, maintains an ideal sandblasting effect, even surpassing that of poorly water-soluble granular materials. This allows for the removal of old paint or iron oxide scale through high-speed impact, while also producing a certain degree of roughness.

[0015] In this invention, a small amount of sodium metal salt is added. The sodium metal salt can dissolve rapidly on the surface of the metal substrate and form a passivation / precipitation film through interaction with iron atoms. From an electrochemical perspective, this increases the self-corrosion potential of iron, effectively solving the flash rust problem caused by water blasting operations, eliminating the need for grinding or roughening, and thus improving on-site construction efficiency.

[0016] In this invention, a small amount of borate is added. Since borate has a strong adsorption effect on metal, it can form a uniform hydrophobic protective film on the metal surface. On the one hand, it replaces the moisture on the surface of the passivation / precipitation film layer, and on the other hand, it can replace the moisture in the tiny pores not covered by the passivation / precipitation film layer, thereby further improving the rust prevention effect.

[0017] In this invention, a small amount of sulfonate is added. On the one hand, sulfonate is composed of hydrophilic and hydrophobic groups. After sulfonate dissolves in water, the hydrophilic groups are adsorbed on the metal surface, and the hydrophobic groups are oriented on the metal surface, which plays a role in shielding moisture. On the other hand, as a surfactant, sulfonate can effectively remove residual oil stains on the metal surface, making the coated surface brighter and cleaner. Attached Figure Description

[0018] Figure 1 The image shows the surface morphology of the steel substrate prepared in Example 1 after abrasive water blasting treatment and left to stand naturally for 24 hours.

[0019] Figure 2 The image shows the surface morphology of the steel substrate treated with abrasive water blasting as prepared in Example 2 after being left to stand naturally for 24 hours.

[0020] Figure 3The image shows the surface morphology of the steel substrate treated with abrasive water blasting as prepared in Example 3 after being left to stand naturally for 24 hours.

[0021] Figure 4 The image shows the surface morphology of the steel substrate treated with abrasive water blasting as prepared in Comparative Example 1 after being left to stand naturally for 24 hours.

[0022] Figure 5 The image shows the surface morphology of the steel substrate treated with abrasive water blasting as prepared in Comparative Example 2 after being left to stand naturally for 300 hours. Detailed Implementation

[0023] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] An environmentally friendly rust-preventive abrasive for water blasting, comprising, by weight parts:

[0025]

[0026] The white sugar in question is industrial grade white sugar, with a mesh size of 60-80 mesh.

[0027] The metallic sodium salt is one or a combination of several of the following: sodium carbonate, sodium bicarbonate, sodium molybdate, sodium phosphate, and sodium gluconate.

[0028] The borate esters are triethanolamine borate and / or diethanolamine borate.

[0029] Sulfonates are one or a combination of several of the following: water-soluble sodium petroleum sulfonate, water-soluble ammonium petroleum sulfonate, and water-soluble potassium petroleum sulfonate.

[0030] Add granulated sugar, sodium metal salt, borate ester, and sulfonate into a powder mixer and mix at 1-3 r / min for 30-60 minutes.

[0031] Example 1

[0032] An environmentally friendly, rust-preventive abrasive for water blasting, comprising the following components by weight:

[0033]

[0034] The white sugar in question is industrial grade, with a mesh size of 60.

[0035] The above-mentioned white sugar, sodium molybdate, sodium phosphate, triethanolamine borate, and water-soluble sodium petroleum sulfonate are sequentially added to a powder mixer for physical mixing. The mixing speed is set to 1 r / min and the mixing time is 60 min. After mixing is completed, the mixture is discharged and packaged.

[0036] The rust-preventive abrasive prepared in this embodiment is added to the abrasive tank. A hose is used to connect to the nozzle of a negative pressure sandblasting machine. The nozzle pressure is set to 50 kg. The high-speed flow of water generates negative pressure in the nozzle, which attracts the abrasive in the abrasive tank to mix into the water flow. The water flow carries the abrasive (the mass ratio of water to abrasive is 3:1) and impacts the surface of the steel substrate quickly and evenly (the duration of water sandblasting impact on each part of the substrate surface is about 10 seconds, the same below), so as to remove old paint or iron oxide scale.

[0037] The surface cleanliness of the steel substrate treated with the above water blasting reached Sa2. After being left to stand naturally for 24 hours, the surface morphology of the steel substrate is shown in the attached figure. Figure 1 As shown, the substrate surface is almost free of rust spots; simultaneously, using a salt content tester, the surface salt residue of the steel substrate at this time is 28 mg / m³. 2 It meets the requirement that "the surface salt content of the substrate is less than 50 mg / m³". 2 The construction standard is "".

[0038] Example 2

[0039] An environmentally friendly, rust-preventive abrasive for water blasting, comprising the following components by weight:

[0040]

[0041] The white sugar in question is industrial grade, with a mesh size of 60.

[0042] The above-mentioned white sugar, sodium bicarbonate, sodium gluconate, diethanolamine borate, and water-soluble petroleum sulfonate are sequentially added to a powder mixer for physical mixing. The mixing speed is set to 3 r / min and the mixing time is 30 min. After mixing is completed, the mixture is discharged and packaged.

[0043] The rust-preventive abrasive prepared in this embodiment is added to the abrasive tank. A hose is used to connect to the nozzle of the negative pressure sandblasting machine. The nozzle pressure is set to 50 kg. The high-speed flow of water generates negative pressure in the nozzle, which attracts the abrasive in the abrasive tank to mix into the water flow. The water flow carries the abrasive (the mass ratio of water to abrasive is 3:1) and impacts the surface of the steel substrate quickly and evenly to remove old paint or iron oxide scale.

[0044] The surface cleanliness of the steel substrate treated with the above water blasting reached Sa2. After being left to stand naturally for 24 hours, the surface morphology of the steel substrate is shown in the attached figure. Figure 2As shown, the substrate surface is almost free of rust spots; simultaneously, using a salt content tester, the surface salt residue of the steel substrate at this time is 36 mg / m³. 2 It meets the requirement that "the surface salt content of the substrate is less than 50 mg / m³". 2 The construction standard is "".

[0045] Example 3

[0046] An environmentally friendly, rust-preventive abrasive for water blasting, comprising the following components by weight:

[0047]

[0048] The white sugar in question is industrial grade, with a mesh size of 80.

[0049] The above-mentioned white sugar, sodium carbonate, sodium phosphate, diethanolamine borate, and water-soluble petroleum sulfonate are sequentially added to a powder mixer for physical mixing. The mixing speed is set to 2 r / min and the mixing time is 40 min. After mixing is completed, the mixture is discharged and packaged.

[0050] The rust-preventive abrasive prepared in this embodiment is added to the abrasive tank. A hose is used to connect to the nozzle of the negative pressure sandblasting machine. The nozzle pressure is set to 50 kg. The high-speed flow of water generates negative pressure in the nozzle, which attracts the abrasive in the abrasive tank to mix into the water flow. The water flow carries the abrasive (the mass ratio of water to abrasive is 3:1) and impacts the surface of the steel substrate quickly and evenly to remove old paint or iron oxide scale.

[0051] The surface cleanliness of the steel substrate treated with the above water blasting reached Sa2. After being left to stand naturally for 24 hours, the surface morphology of the steel substrate is shown in the attached figure. Figure 3 As shown, the substrate surface is almost free of rust spots; simultaneously, using a salt content tester, the surface salt residue of the steel substrate at this time is 44 mg / m³. 2 It meets the requirement that "the surface salt content of the substrate is less than 50 mg / m³". 2 The construction standard is "".

[0052] Comparative Example 1

[0053] Garnet (60 mesh) was added directly to the abrasive tank instead of the anti-rust abrasive in Example 1. A hose was used to connect to the nozzle of a negative pressure sandblasting machine. The nozzle pressure was set to 50 kg. The high-speed flow of water created negative pressure in the nozzle, which attracted the white sugar in the abrasive tank into the water flow. The water flow carried the white sugar abrasive (the mass ratio of water to white sugar was 3:1) and quickly and evenly impacted the surface of the steel substrate, which was from the same batch as in Example 1 and stored under the same conditions (i.e., the surface condition of the substrate was similar before sandblasting, the same below), to remove old paint or iron oxide scale.

[0054] The surface cleanliness of the steel substrate treated with the above water blasting reached Sa2.5, but after being left to stand naturally for 24 hours, the surface morphology of the steel substrate is as shown in the attached figure. Figure 4 As shown, a large amount of rust appeared on the surface of the substrate. This is because the abrasive used in Comparative Example 1 did not have rust-preventing properties.

[0055] Comparative Example 2

[0056] Use sodium bicarbonate of the same mesh size instead of white sugar in Example 1, and keep all other components and operations the same as in Example 1:

[0057] An environmentally friendly, rust-preventive abrasive for water blasting, comprising the following components by weight:

[0058]

[0059] Sodium bicarbonate has a mesh size of 60.

[0060] Sodium bicarbonate, sodium molybdate, sodium phosphate, triethanolamine borate, and water-soluble sodium petroleum sulfonate are sequentially added to a powder mixer for physical mixing. The mixing speed is set to 1 r / min, and the mixing time is 60 min. After mixing is completed, the mixture is discharged and packaged.

[0061] The rust-resistant abrasive prepared in this comparative embodiment is added to the abrasive tank. A hose is used to connect to the nozzle of a negative pressure sandblasting machine. The nozzle pressure is set to 50 kg. The high-speed flow of water generates negative pressure in the nozzle, which attracts the abrasive in the abrasive tank and mixes it into the water flow. The water flow carries the abrasive (the mass ratio of water to abrasive is 3:1) and rapidly and uniformly impacts the surface of the steel substrate, which is from the same batch as in Example 1 and is stored under the same conditions, to remove old paint or iron oxide scale.

[0062] The surface cleanliness of the steel substrate treated with the above water blasting reached Sa2. The cleanliness level is at the same level as in Example 1. However, in Comparative Example 2, the solubility of sodium bicarbonate in water at room temperature is only about 10g, which is far lower than the solubility of white sugar in water at room temperature of "more than 200g". However, judging from the blasting effect, white sugar is not worse than sodium bicarbonate abrasive. It can be seen that the characteristic of white sugar "good water solubility and rapid dissolution in water" does not affect the impact on the substrate or the blasting effect.

[0063] Meanwhile, after the steel substrate treated with the above water blasting was left to stand naturally for 24 hours, although its surface was as smooth as new, the salt content on the surface of the steel substrate was found to be seriously excessive, reaching 1000 mg / m³, according to the salt content tester. 2 .

[0064] Neutral salt spray resistance tests (GB / T1771-2007, GB / T1766-2008) revealed that after the coating was cured on the steel substrate treated with water blasting, blistering occurred in less than 300 hours. (See attached image.) Figure 5 This severely affects the anti-corrosion performance of the coating.

[0065] Comparative Example 3

[0066] Use barium acetate of the same mesh size instead of white sugar in Example 1, and keep all other components and operations the same as in Example 1:

[0067] An environmentally friendly, rust-preventive abrasive for water blasting, comprising the following components by weight:

[0068]

[0069] Among them, the barium acetate mesh number is 60 mesh,

[0070] The above-mentioned barium acetate, sodium molybdate, sodium phosphate, triethanolamine borate, and water-soluble sodium petroleum sulfonate are sequentially added to a powder mixer for physical mixing. The mixing speed is set to 1 r / min and the mixing time is 60 min. After mixing is completed, the mixture is discharged and packaged.

[0071] The rust-resistant abrasive prepared in this comparative embodiment is added to the abrasive tank. A hose is used to connect to the nozzle of a negative pressure sandblasting machine. The nozzle pressure is set to 50 kg. The high-speed flow of water generates negative pressure in the nozzle, which attracts the abrasive in the abrasive tank and mixes it into the water flow. The water flow carries the abrasive (the mass ratio of water to abrasive is 3:1) and rapidly and uniformly impacts the surface of the steel substrate, which is from the same batch as in Example 1 and is stored under the same conditions, to remove old paint or iron oxide scale.

[0072] The surface cleanliness of the steel substrate treated with the above water blasting reached Sa1.

[0073] In Comparative Example 3, the solubility of barium acetate in water at room temperature was between 70 and 80 g, a significant increase compared to sodium bicarbonate in Comparative Example 2. However, its sandblasting effect decreased accordingly. The applicant believes this is precisely because barium acetate has high water solubility and dissolves rapidly in water. It is evident that barium acetate, when used as a water-soluble abrasive, does not possess the sandblasting effect of granulated sugar, especially since its solubility is far inferior to that of granulated sugar. This is one reason why granulated sugar was chosen as the abrasive in this solution: without affecting the sandblasting effect, its extremely high solubility allows it to dissolve quickly in water, solving the abrasive recovery problem faced after the completion of traditional water blasting processes.

[0074] Comparative Example 4

[0075] Use potassium sorbate of the same mesh size instead of white sugar in Example 1; all other components and procedures are the same as in Example 1.

[0076] An environmentally friendly, rust-preventive abrasive for water blasting, comprising the following components by weight:

[0077]

[0078] Among them, potassium sorbate has a mesh size of 60 mesh.

[0079] The potassium sorbate, sodium molybdate, sodium phosphate, triethanolamine borate, and water-soluble sodium petroleum sulfonate were sequentially added to a powder mixer and physically mixed. The mixing speed was set to 1 r / min and the mixing time was 60 min. After mixing was completed, the mixture was discharged and packaged.

[0080] The rust-resistant abrasive prepared in this comparative embodiment is added to the abrasive tank. A hose is used to connect to the nozzle of a negative pressure sandblasting machine. The nozzle pressure is set to 50 kg. The high-speed flow of water generates negative pressure in the nozzle, which attracts the abrasive in the abrasive tank and mixes it into the water flow. The water flow carries the abrasive (the mass ratio of water to abrasive is 3:1) and rapidly and uniformly impacts the surface of the steel substrate, which is from the same batch as in Example 1 and is stored under the same conditions, to remove old paint or iron oxide scale.

[0081] The surface cleanliness of the steel substrate treated with the above water blasting reached Sa1. The blasting effect was relatively unsatisfactory. The applicant believes that this is also due to the high water solubility of potassium sorbate, which dissolves rapidly in water.

[0082] Meanwhile, after the steel substrate treated with the above water blasting was left to stand naturally for 24 hours, a salt content tester was used to test the surface salt content of the steel substrate. At this time, the salt content of the steel substrate was seriously excessive, reaching 730 mg / m³. 2 .

[0083] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. An environmentally friendly water-jet sandblasting method for rust prevention, characterized in that: The abrasive comprises, by weight parts 80-90 parts white sugar 5-10 parts of metallic sodium salt 3-5 parts of borate ester 2-5 parts of sulfonate, The method includes: adding the abrasive into an abrasive tank, connecting a hose to a negative pressure sandblasting machine nozzle, setting the nozzle pressure to 50 kg, and using the high-speed flow of water to generate negative pressure in the nozzle to attract the abrasive from the abrasive tank into the water flow, so that the water flow carries the abrasive to rapidly and evenly impact the surface of the steel substrate to remove old paint or iron oxide scale. The white granulated sugar is industrial grade white granulated sugar with a mesh size of 60-80 mesh; The mass ratio of water to abrasive is 3:

1.

2. The environmentally friendly rust-preventing abrasive water blasting method as described in claim 1, characterized in that: The sodium salt is one or a combination of several of sodium carbonate, sodium bicarbonate, sodium molybdate, sodium phosphate, and sodium gluconate.

3. The environmentally friendly rust-preventing abrasive water blasting method as described in claim 1, characterized in that: The borate ester is triethanolamine borate and / or diethanolamine borate.

4. The environmentally friendly rust-preventing abrasive water blasting method as described in claim 1, characterized in that: The sulfonate is one or a combination of several of water-soluble sodium petroleum sulfonate, water-soluble ammonium petroleum sulfonate, and water-soluble potassium petroleum sulfonate.

5. A method for preparing the abrasive in the environmentally friendly rust-preventing abrasive water blasting method as described in any one of claims 1 to 4, characterized in that: The preparation method involves adding white sugar, sodium metal salt, borate ester, and sulfonate into a powder mixer and mixing thoroughly.

6. The method for preparing the abrasive as described in claim 5, characterized in that: The stirring speed is 1 to 3 r / min.

7. The method for preparing the abrasive as described in claim 5, characterized in that: The stirring time is 30 to 60 minutes.

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