Method for preventing corrosion in blast-furnace or converter gas pipeline

Abstract

The invention relates to a method for preventing the corrosion in a blast-furnace or converter gas pipeline. The method is characterized by comprising the following steps that 1, the surface of the gas pipeline is pretreated and cleaned, specifically, the surface of the gas pipeline needs to be cleaned before being brushed, and moisture, dust and oil stains cannot be generated; 2, a primer is brushed, specifically, a water-based inorganic anti-corrosion material is adopted, Chem-CreteASP is added into the water-based inorganic anti-corrosion material so as to form a mixture, and the mixture and water are mixed and are stirred and mixed with power so as to form the primer; and 3, finish paint is brushed, specifically, the finish paint adopts polyurethane enamel paint and is brushed twice, and the total dry film thickness is greater than or equal to 250 microns. The method has the advantages that construction is simple, mechanical spraying or manual brushing can be realized, the water permeability of a gas medium and condensate water can be reduced, the expansion coefficient of steel material can be met, the thermal shock performance of an anti-corrosion coating in the pipeline can be improved, the hardness of the coating can be improved, the were resistance of the pipeline can be enhanced, the bonding strength, the adhesive force and the shock strength of the coating and the pipeline can be enhanced, and the service life of the blast-furnace or converter gas pipeline and associated equipment can be prolonged.

Description

technical field [0001] The invention relates to the technical field of gas pipelines, in particular to an internal anti-corrosion method for high-speed and converter gas pipelines. Background technique [0002] The anti-corrosion work of gas pipelines (especially blast furnace and converter gas pipelines) is facing great challenges. The conventional internal and external anti-corrosion methods mainly have the following disadvantages: 1. Conventional anti-corrosion, the covering layer has a long curing time and is greatly affected by the environment. It is not suitable for field operations and areas with high air humidity, and it is difficult to construct below 10°C; 2. The construction process is cumbersome. The working conditions are poor, and the construction quality is not easy to control; 3. The waterproofness of epoxy powder is poor (the water absorption rate is high, reaching 0.83%). On-site equipment requires high requirements, difficult operation, and difficult qual...

AI Technical Summary

Problems solved by technology

The conventional internal and external anti-corrosion methods mainly have the following disadvantages: 1. Conventional anti-corrosion, the covering layer has a long curing time and is greatly affected by the environment. It is not suitable for field operations and areas with high air humidity, and it is difficult to construct below 10°C; 2. The construction process is cumbersome. The working conditions are poor, and the construction quality is not easy to control; 3. The waterproofness of epoxy powder is poor (the water absorption rate is high, reaching 0.83%)

On-site equipment requires high requirements, difficult operation, and difficult quality control; 4. The anti-corrosion time is short, generally 3-5 years; 5. Conventional anti-corrosion materials contain many toxic and harmful components and pollute the environment; 6. High, corrosive components of converter gas Many, such as SO2, SO3, Cl2, H2S, etc., the corrosion rate of the condensed water hanging piece of the dry dust removal pipeline is two orders of magnitude (about 50 times) higher than that of the wet dust removal, and the common anti-corrosion form (such as epoxy coal tar pitch, etc.) ) cannot meet the needs of safe production; 7. High, the pH of the medium inside the converter gas pipeline is between 2 and 6, and water will precipitate after the temperature drops. The water contains harmful substances such as chloride ions, sulfate ions, and trace fluoride ions.

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