Anti-corrosion method for air condensation pipeline in environment-friendly equipment

Abstract

The invention provides an anti-corrosion method for an air condensation pipeline in environmental protection equipment, which comprises the following steps: 1) horizontally placing the air condensation pipeline on a plurality of roller carriers, and driving a driving roller to rotate by a motor so as to drive the air condensation pipeline to rotate; 2) pickling; 3) washing with water; 4) welding an aluminum-zinc alloy strip; 5) washing with a plating assistant; (6) spraying slurry containing zinc powder; 7) drying; 8) heating to form a molten, solidified and connected hot galvanizing layer; (9) blowing and cooling; and (10) corrosion prevention of the outer wall. The hot-dip galvanizing layer and the inner wall surface of the pipe wall are indirectly fused, solidified and connected together by using the aluminum-zinc alloy belt as an intermediate, so that the binding force is improved, and the pipe is more resistant to cracking and falling off; the latticed aluminum-zinc alloy belt divides the whole large-area hot-dip galvanizing layer into small pieces of small-area separated hot-dip galvanizing layers, a separation protection structure is formed, the service life of the whole hot-dip galvanizing layer in the air condensation pipeline is prolonged, and the use performance of the whole hot-dip galvanizing layer in the air condensation pipeline is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of pipeline anti-corrosion, and in particular relates to an anti-corrosion method for an air condensation pipeline in environmental protection equipment. Background Art

[0002] Pipeline corrosion protection is a protective technology to prevent pipelines from being corroded by soil, air and conveying media (air, oil, natural gas). According to the corroded parts of the pipeline, it can be divided into inner wall corrosion and outer wall corrosion; according to the pipeline corrosion form, it can be divided into overall corrosion and local corrosion; according to the pipeline corrosion mechanism, it can be divided into chemical corrosion and electrochemical corrosion. Anti-corrosion methods include coating anti-corrosion and electrical protection, including inner wall anti-corrosion and outer wall anti-corrosion.

[0003] Hot-dip galvanized pipes are made by reacting molten metal zinc with an iron matrix to produce an alloy layer, thereby combining the matrix and the coating; hot-dip galvanizing has the advantages of uniform coating, strong adhesion, and long service life. The hot-dip galvanized steel pipe matrix undergoes complex physical and chemical reactions with the molten zinc liquid to form a corrosion-resistant and tightly structured zinc-iron alloy layer. The alloy layer is integrated with the pure zinc layer and the steel pipe matrix, so it has strong corrosion resistance. Galvanized pipes are widely used. In addition to being used as pipeline pipes for general low-pressure fluids such as water, gas, and oil, they are also used as oil well pipes and oil pipelines in the petroleum industry, especially offshore oil fields, oil heaters, condenser coolers, coal distillation and washing oil exchangers for chemical coking equipment, and pier pipe piles and support frames for mine tunnels. Hot-dip galvanized pipes are usually small-diameter steel pipes.

[0004] The air condensation duct in the environmental protection equipment is used to cool the air and condense the moisture in the air into water to remove the water in the air; the size of the air condensation duct is very large, with an inner diameter of 1.5-2.5 meters and a length of 5m-20m. Adult workers can stand in the pipe to carry out construction, and the condensation duct is usually provided with multiple flange openings, etc. It is a special-shaped part and the number is very small. Therefore, the condensation duct is basically inconvenient or even impossible to adopt traditional pipeline anti-corrosion methods and the above-mentioned hot-dip galvanized steel pipe anti-corrosion methods. For example: hot-dip galvanizing is definitely better than anti-corrosion coatings in anti-corrosion effect, but due to the huge size of the condensation duct and the small number, it is not worthwhile and unrealistic to dig a galvanized trough larger than the volume of the condensation duct and use it only a few times. Summary of the invention

[0005] The purpose of the invention is to provide an anti-corrosion method for air condensation pipelines in environmental protection equipment.

[0006] In order to achieve the above object, the technical solution of the present invention is as follows:

[0007] A method for anti-corrosion of an air condensation pipeline in an environmental protection device comprises the following steps performed in sequence:

[0008] 1) The air condensation pipe is horizontally placed on multiple roller racks, and the motor drives the active roller to rotate, thereby driving the air condensation pipe to rotate;

[0009] 2) Add pickling liquid into the air condensation pipeline for pickling while rotating, and discharge the waste pickling liquid after pickling;

[0010] 3) Then add water to the air condensation pipeline to wash it while rotating, and discharge the waste water after washing;

[0011] 4) Using a handheld spot welder, the aluminum-zinc alloy strip is welded and fixed on the inner wall surface of the air condensation duct, and the transverse aluminum-zinc alloy strip and the longitudinal aluminum-zinc alloy strip form a grid shape;

[0012] 5) Add plating aid into the air condensation pipe to wash the plating aid while rotating, and discharge the waste plating aid after washing;

[0013] 6) stirring and mixing the zinc powder and the binder to form a slurry, and then spraying the slurry on the inner wall surface of the air condensation pipe by using a pressure spray gun, and rotating the air condensation pipe while spraying to form a wet coating;

[0014] 7) A plurality of natural gas burners are arranged below the outside of the air condensation pipe, and the natural gas burners burn natural gas to heat the air condensation pipe while rotating, and heat the pipe wall of the air condensation pipe to 90° C.-110° C. to dry the wet coating into a dry coating;

[0015] 8) Increase the flow rate of natural gas and air to increase the flame temperature, and then heat the pipe wall of the air condensation pipe to 430°C-445°C while rotating to melt the metal zinc in the dry coating, and the molten zinc liquid reacts with the inner wall of the pipe to form a zinc-iron alloy, and the molten zinc liquid is melted and solidified with the heated aluminum-zinc alloy strip to be connected together, and the zinc in the heated aluminum-zinc alloy strip is melted to form a zinc liquid that reacts with the inner wall of the pipe to form a zinc-iron alloy, thereby forming a hot-dip galvanizing layer;

[0016] 9) Multiple blower air guns are arranged below the outside of the air condensation duct, and the air condensation duct is cooled by blowing air while rotating using the blower air guns;

[0017] 10) Use a pressure spray gun to spray the anti-corrosion coating on the outer wall of the air condensation duct, and rotate the air condensation duct while spraying, and after completion, an air condensation duct with anti-corrosion on the inner wall and the outer wall is obtained.

[0018] Preferably, the plating assistant is NH4Cl solution.

[0019] Preferably, in the aluminum-zinc alloy strip, the mass percentage of zinc is 30%-40%, and the balance is aluminum;

[0020] The aluminum-zinc alloy strip has a width of 8-15 mm and a thickness of 1-3 mm.

[0021] Preferably, the adhesive is liquid epoxy resin.

[0022] Preferably, the anti-corrosion coating is a zinc-rich epoxy anti-rust primer and a zinc-rich epoxy anti-corrosion topcoat.

[0023] This application has achieved the following beneficial technical effects:

[0024] (1) Since hot-dip galvanizing is definitely better than anti-corrosion coating in terms of anti-corrosion effect, the present application overcomes the difficulties of large size, special-shaped parts and small number of air condensation pipes, and firstly sprays a slurry containing zinc powder while rotating, and then rotates and burns a natural gas burner for external heating, so that the pipe wall is heated to the zinc liquid temperature of 430°C-445°C for hot-dip galvanizing, forming a hot-dip galvanized layer. Although the bonding strength, uniformity and other properties of the hot-dip galvanized layer are somewhat inferior to those of the hot-dip galvanized layer of the traditional galvanizing tank, the bonding strength and anti-corrosion effect of the anti-corrosion coating on the inner wall of the current air condensation pipe are better;

[0025] (2) Due to the high temperature melting, the bonding force between the hot-dip galvanizing layer and the substrate is greater than that between the anti-corrosion coating and the substrate; however, due to the huge size of the air condensation duct, the large-area, whole-piece hot-dip galvanizing layer still has defects such as easy cracking and easy falling off;

[0026] To this end, in the present application, a handheld spot welder is used to weld and fix the aluminum-zinc alloy strip on the inner wall surface of the air condensation duct, and the horizontal aluminum-zinc alloy strip and the longitudinal aluminum-zinc alloy strip form a grid; the grid-shaped aluminum-zinc alloy strip is set, firstly, because the aluminum-zinc alloy strip also contains zinc, the molten zinc liquid reacts with the inner wall of the pipe to form a zinc-iron alloy, and the molten zinc liquid is melted and solidified with the heated aluminum-zinc alloy strip and connected together, the zinc in the heated aluminum-zinc alloy strip melts into zinc liquid (the melting point of aluminum is 660°C and it will not melt) and reacts with the inner wall of the pipe to form a zinc-iron alloy, that is, the hot-dip galvanized layer and the aluminum-zinc alloy strip are melted and solidified and connected together (equivalent to fusion welding), and because the aluminum-zinc alloy The gold belt is firmly welded to the inner wall of the pipe wall, thus indirectly connecting the hot-dip galvanized layer to the inner wall of the pipe wall by melting and solidification, that is, the aluminum-zinc alloy belt here is equivalent to the intermediate bridge between the hot-dip galvanized layer and the iron pipe wall, and the hot-dip galvanized layer and the inner wall of the pipe wall are indirectly connected by melting and solidification by using the aluminum-zinc alloy belt as the intermediary. The melting and solidification connection makes the bonding force and bonding strength between the hot-dip galvanized layer and the pipe wall matrix greater. The grid-shaped aluminum-zinc alloy belt is similar to the glass fiber mesh cloth in the surface layer of the building wall. The bonding force and bonding strength of the flat glass fiber mesh cloth embedded in the mortar are definitely greater than those of the simple mortar alone, and the wall is more resistant to cracking and falling off;

[0027] Secondly, the grid-shaped aluminum-zinc alloy strip divides the traditional large-area, whole hot-dip galvanized layer into small, separated hot-dip galvanized layers, forming a separation protection structure. The hot-dip galvanized layer of each small area is smaller in area, and is subjected to less destructive force such as expansion force, thereby making it less likely for the hot-dip galvanized layer of each small area to crack and fall off. When a small area of ​​the hot-dip galvanized layer is damaged, cracked, or falls off, due to the separation protection, each adjacent small area of ​​the hot-dip galvanized layer will not be damaged, thereby protecting the remaining large area of ​​the hot-dip galvanized layer, thereby improving the service life and performance of the entire hot-dip galvanized layer in the air condensation duct. DETAILED DESCRIPTION

[0028] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. The described embodiments are only part of the embodiments of the present invention, not all of them. Therefore, 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.

[0029] The present application provides an anti-corrosion method for an air condensation pipeline in an environmental protection device, comprising the following steps performed in sequence:

[0030] 1) The air condensation pipe is horizontally placed on multiple roller racks, and the motor drives the active roller to rotate, thereby driving the air condensation pipe to rotate;

[0031] 2) Add pickling liquid into the air condensation pipeline for pickling while rotating, and discharge the waste pickling liquid after pickling;

[0032] 3) Then add water to the air condensation pipeline to wash it while rotating, and discharge the waste water after washing;

[0033] 4) Using a handheld spot welder, the aluminum-zinc alloy strip is welded and fixed on the inner wall surface of the air condensation duct, and the transverse aluminum-zinc alloy strip and the longitudinal aluminum-zinc alloy strip form a grid shape;

[0034] 5) Add plating aid into the air condensation pipe to wash the plating aid while rotating, and discharge the waste plating aid after washing;

[0035] 6) stirring and mixing the zinc powder and the binder to form a slurry, and then spraying the slurry on the inner wall surface of the air condensation pipe by using a pressure spray gun, and rotating the air condensation pipe while spraying to form a wet coating;

[0036] 7) A plurality of natural gas burners are arranged below the outside of the air condensation pipe, and the natural gas burners burn natural gas to heat the air condensation pipe while rotating, and heat the pipe wall of the air condensation pipe to 90° C.-110° C. to dry the wet coating into a dry coating;

[0037] 8) Increase the flow rate of natural gas and air to increase the flame temperature, and then heat the pipe wall of the air condensation pipe to 430°C-445°C while rotating to melt the metal zinc in the dry coating, and the molten zinc liquid reacts with the inner wall of the pipe to form a zinc-iron alloy, and the molten zinc liquid is melted and solidified with the heated aluminum-zinc alloy strip to be connected together, and the zinc in the heated aluminum-zinc alloy strip is melted to form a zinc liquid that reacts with the inner wall of the pipe to form a zinc-iron alloy, thereby forming a hot-dip galvanizing layer;

[0038] 9) Multiple blower air guns are arranged below the outside of the air condensation duct, and the air condensation duct is cooled by blowing air while rotating using the blower air guns;

[0039] 10) Use a pressure spray gun to spray the anti-corrosion coating on the outer wall of the air condensation duct, and rotate the air condensation duct while spraying, and after completion, an air condensation duct with anti-corrosion on the inner wall and the outer wall is obtained.

[0040] In one embodiment of the present application, the plating assistant is NH4Cl solution.

[0041] In one embodiment of the present application, in the aluminum-zinc alloy strip, the mass percentage content of zinc is 30%-40%, and the balance is aluminum;

[0042] The aluminum-zinc alloy strip has a width of 8-15 mm and a thickness of 1-3 mm.

[0043] In one embodiment of the present application, the adhesive is liquid epoxy resin.

[0044] In one embodiment of the present application, the anti-corrosion coating is a zinc-rich epoxy anti-rust primer and a zinc-rich epoxy anti-corrosion topcoat.

[0045] In the present application, hot-dip galvanizing is to react molten metal zinc with an iron substrate to produce an alloy layer, thereby combining the substrate and the coating; hot-dip galvanizing is to first pickle the steel parts to remove iron oxide on the surface of the steel parts, then wash them in an ammonium chloride or zinc chloride aqueous solution or a mixed aqueous solution of ammonium chloride and zinc chloride, and then perform hot-dip galvanizing.

[0046] In the present application, spot welding refers to a welding method in which a columnar electrode is used to form a weld between the contact surfaces of two overlapping workpieces. During spot welding, pressure is first applied to bring the workpieces into close contact, and then an electric current is turned on. The contact between the workpieces melts under the action of resistance heat, and a weld is formed after cooling. Spot welding is mainly used for welding thin plate components with a thickness of less than 4 mm, and is particularly suitable for welding automobile bodies, carriages, and aircraft fuselages. Spot welding is a type of resistance welding, which consumes only electrical energy and does not require filling materials or flux, gas, etc.

[0047] The methods and devices not described in detail in the present invention are all prior art and will not be described in detail.

[0048] In order to better understand the present invention, the present invention is further specifically described below through the following examples, but it should not be understood as a limitation of the present invention. Some non-essential improvements and adjustments made by technicians in this field based on the above invention content are also considered to fall within the protection scope of the present invention.

[0049] Example 1

[0050] A method for anti-corrosion of an air condensation pipeline in an environmental protection device comprises the following steps performed in sequence:

[0051] 1) The air condensation pipe is horizontally placed on multiple roller racks, and the motor drives the active roller to rotate, thereby driving the air condensation pipe to rotate;

[0052] 2) Add pickling liquid into the air condensation pipeline for pickling while rotating, and discharge the waste pickling liquid after pickling;

[0053] 3) Then add water to the air condensation pipeline to wash it while rotating, and discharge the waste water after washing;

[0054] 4) Using a handheld spot welder, the aluminum-zinc alloy strip is welded and fixed on the inner wall surface of the air condensation duct, and the transverse aluminum-zinc alloy strip and the longitudinal aluminum-zinc alloy strip form a grid shape;

[0055] The aluminum-zinc alloy strip has a zinc content of 30% by mass and the remainder being aluminum;

[0056] The aluminum-zinc alloy strip has a width of 8 mm and a thickness of 2.5 mm;

[0057] 5) Add plating aid into the air condensation pipe to wash the plating aid while rotating, and discharge the waste plating aid after washing;

[0058] The plating auxiliary agent is NH4Cl aqueous solution;

[0059] 6) stirring and mixing the zinc powder and the binder to form a slurry, and then spraying the slurry on the inner wall surface of the air condensation pipe by using a pressure spray gun, and rotating the air condensation pipe while spraying to form a wet coating;

[0060] The adhesive is liquid epoxy resin;

[0061] 7) A plurality of natural gas burners are arranged below the outside of the air condensation pipe, and the natural gas burners burn natural gas to heat the air condensation pipe while rotating, and heat the pipe wall of the air condensation pipe to 90°C-95°C to dry the wet coating into a dry coating;

[0062] 8) Increasing the flow of natural gas and air to increase the flame temperature, thereby heating the pipe wall of the air condensation pipe to 430°C-440°C, and the air condensation pipe is heated while rotating to melt the metal zinc in the dry coating, and the molten zinc liquid reacts with the inner wall of the pipe to form a zinc-iron alloy, and the molten zinc liquid is melted and solidified with the heated aluminum-zinc alloy strip to be connected together, and the zinc in the heated aluminum-zinc alloy strip is melted to form a zinc liquid that reacts with the inner wall of the pipe to form a zinc-iron alloy, thereby forming a hot-dip galvanizing layer;

[0063] 9) Multiple blower air guns are arranged below the outside of the air condensation duct, and the air condensation duct is cooled by blowing air while rotating using the blower air guns;

[0064] 10) Using a pressure spray gun, spray the anti-corrosion coating on the outer wall of the air condensation pipe, and rotate the air condensation pipe while spraying, and after completion, the air condensation pipe with anti-corrosion on the inner wall and the anti-corrosion on the outer wall is obtained;

[0065] The anti-corrosion coating is zinc-rich epoxy anti-rust primer and zinc-rich epoxy anti-corrosion topcoat.

[0066] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for anti-corrosion of air condensation pipes in environmental protection equipment, characterized in that: The method includes the following steps in sequence: 1) The air condensation pipe is horizontally placed on multiple roller racks, and the motor drives the active roller to rotate, thereby driving the air condensation pipe to rotate; 2) Add pickling liquid into the air condensation pipeline for pickling while rotating, and discharge the waste pickling liquid after pickling; 3) Then add water to the air condensation pipeline to wash it while rotating, and discharge the waste water after washing; 4) Using a handheld spot welder, the aluminum-zinc alloy strip is welded and fixed on the inner wall surface of the air condensation duct, and the transverse aluminum-zinc alloy strip and the longitudinal aluminum-zinc alloy strip form a grid shape; 5) Add plating aid into the air condensation pipe to wash the plating aid while rotating, and discharge the waste plating aid after washing; 6) stirring and mixing the zinc powder and the binder to form a slurry, and then spraying the slurry on the inner wall surface of the air condensation pipe by using a pressure spray gun, and rotating the air condensation pipe while spraying to form a wet coating; 7) A plurality of natural gas burners are arranged below the outside of the air condensation pipe, and the natural gas burners burn natural gas to heat the air condensation pipe while rotating, and heat the pipe wall of the air condensation pipe to 90°C-110°C to dry the wet coating into a dry coating; 8) Increase the flow rate of natural gas and air to increase the flame temperature, and then heat the pipe wall of the air condensation pipe to 430°C-445°C while rotating to melt the metal zinc in the dry coating, and the molten zinc liquid reacts with the inner wall of the pipe to form a zinc-iron alloy, and the molten zinc liquid is melted and solidified with the heated aluminum-zinc alloy strip to be connected together, and the zinc in the heated aluminum-zinc alloy strip is melted to form a zinc liquid that reacts with the inner wall of the pipe to form a zinc-iron alloy, thereby forming a hot-dip galvanizing layer; 9) Multiple blower air guns are arranged below the outside of the air condensation duct, and the air condensation duct is cooled by blowing air while rotating using the blower air guns; 10) Use a pressure spray gun to spray the anti-corrosion coating on the outer wall of the air condensation duct, and rotate the air condensation duct while spraying, and after completion, an air condensation duct with anti-corrosion on the inner wall and the outer wall is obtained.

2. The anti-corrosion method for air condensation pipes in environmental protection equipment according to claim 1, characterized in that: The plating assistant is NH4Cl solution.

3. The anti-corrosion method for air condensation pipes in environmental protection equipment according to claim 1, characterized in that: In the aluminum-zinc alloy strip, the mass percentage of zinc is 30%-40%, and the balance is aluminum; The aluminum-zinc alloy strip has a width of 8-15 mm and a thickness of 1-3 mm.

4. The anti-corrosion method for air condensation pipes in environmental protection equipment according to claim 1, characterized in that: The adhesive is liquid epoxy resin.

5. The anti-corrosion method for air condensation pipes in environmental protection equipment according to claim 1, characterized in that: The anti-corrosion coating is zinc-rich epoxy anti-rust primer and zinc-rich epoxy anti-corrosion topcoat.