Graphene coating for corrosion prevention of thermal power plant desulfurization chimney, and preparation method of graphene coating

Abstract

The invention discloses graphene coating for corrosion prevention of a thermal power plant desulfurization chimney. The graphene coating consists of the following raw materials in parts by weight: 90 to 100 parts of film-forming resin, 0.5 to 3 parts of graphene, 0.5 to 2 parts of reinforced fibers, 10 to 20 parts of fillers, 10 to 20 parts of a curing agent, 15 to 30 parts of a diluents, 1 to 5 parts of polyacrylic acid, 1 to 5 parts of a polyethylenimin crosslinking agent, 1 to 3 parts of stearate and 2 to 6 parts of aids. By the mode of adding the raw materials, such as the reinforced fibers, the fillers, the polyethylenimin crosslinking agent and the polyacrylic acid, the defect that the existing corrosion-resistant coating has low durability and heat stability is overcome, the problem that the corrosion-resistant coating layer is easy to pollute and difficult to clean is solved, the developed graphene corrosion-resistant coating can completely adapt to the high-temperature strong-acid environment, the manufacturing process is simple, the practicability is high and the graphene coating is particularly suitable for thermal power plant desulfurization chimneys and flues.

Description

technical field [0001] The invention relates to the field of anticorrosion of thermal power desulfurization chimneys, in particular to a method for preparing a graphene coating for anticorrosion of desulfurization chimneys of thermal power plants. Background technique [0002] At present, with the implementation of the national energy conservation and emission reduction strategy, the national environmental protection policy requires the thermal power industry to compel the installation of desulfurization system devices. In today's wet limestone desulfurization process, although the content of sulfur dioxide in the flue gas is greatly reduced after treatment, the humidity of the flue gas increases after desulfurization, and the flue gas will condense on the walls of the absorption tower and other devices, which will bring sulfuric acid in the desulfurization process. Gas hydrolysis will form a corrosive environment with different low pH values, forming a highly corrosive acid...

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Problems solved by technology

However, there are three problems with this coating: 1. The thermal conductivity of vinyl resin is poor, and its heat distortion temperature is between 120-135°C, while the temperature of industrial waste gas treated by desulfurization and denitrification towers is generally 200-300°C, even if the desulfurization and denitrification tower The temperature of the final net flue gas is also around 100°C. After the desulfurization tower works for a long time, the temperature of the anti-corrosion coating is relatively high due to poor heat dissipation. Defects such as deformation, microcracks, and thermal decomposition of the coating make the durability and thermal stability of the anti-corrosion coating lower and the service life shorter, and these problems cannot be solved by graphene nanosheets alone; 2. Smoke It often contains a certain amount of water mist and dust, which causes more dirt to adhere to the surface of the anti-corrosion coating and is not easy to clean. Workers often need to enter the tower to clean it, which is labor-consuming and time-consuming; 3. Graphene nanosheets are a new type of The material (see another invention patent 201410617460.9 of the applicant for details) requires special manufacturing, which not only increases the process flow and process cost, but also has poor adaptability and weak versatility, and greatly limits market promotion and application

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