Boiler flue equal-service-life high-temperature anti-corrosion coating composite material and application thereof

Abstract

The invention relates to a boiler flue equal-service-life high-temperature anti-corrosion coating composite material. The material comprises a first nickel-based self-fluxing alloy coating material, asecond nickel-based self-fluxing alloy coating material, a third nickel-based self-fluxing alloy coating material, a medium-temperature and medium-pressure composite coating material, a medium-temperature and secondary-high-pressure or secondary-high-temperature and secondary-high-pressure composite coating material, a high-temperature and high-pressure composite coating material, a cold-sprayingglass fiber reinforced plastic coating and a polyurethane polymer coating. All the coating materials can be used for preparing high-temperature anti-corrosion coatings in different corrosion areas ofa boiler flue independently or in a combined manner, and an equal-service-life high-temperature anti-corrosion boiler flue is obtained. The boiler flue high-temperature anti-corrosion coating prepared from the coating composite material is utilized, measures can be accurately taken by aiming at a specific boiler profile, an equal-service-life corrosion protection method with high cost performanceis provided under the condition that the service life is not shortened, and meanwhile realizability of the process is kept.

Description

technical field [0001] The invention belongs to the technical field of boiler flue anti-corrosion technology, and relates to a coating composite material for high-temperature anti-corrosion of boiler flue and its application. Background technique [0002] In the process of waste incineration, the boiler usually suffers severe high-temperature corrosion caused by chlorides, sulfides, alkali metals, etc. under high temperature conditions. Surface coating protection is the most commonly used protection method at present. It is mainly aimed at the heating surfaces of the "four tubes" of boilers such as membrane water walls of waste heat boilers and superheaters, reheaters, and economizers. Protection methods such as melting and surface deposition can inhibit or delay corrosion. Among them, thermal spraying is difficult to meet the requirements due to high porosity and low bonding strength; surfacing welding technology has been widely used and achieved good results, but it is be...

AI Technical Summary

Problems solved by technology

The heating surface area of ​​the "four tubes" in a general boiler can reach nearly a thousand or even several thousand square meters, and a general power station has at least two boilers. From this we can see that even a small power station needs tens of millions of anti-corrosion costs, which has brought huge costs to the enterprise. heavy financial burden

In fact, the interior of the boiler is divided into four flues, and the temperature of each flue has a large difference, and the corrosion rate of the high-temperature flue gas varies with the temperature. Even in the end, the occurrence rate of pipe bursts is often concentrated in some parts with the highest high-temperature corrosion rate. For these parts, it is often necessary to shut down the furnace for maintenance or cut and replace the pipes where local pipe bursts occurred. However, most of the other pipes can still be used safely for many years. Even when all the pipelines are scrapped as a whole, they are still basically intact, resulting in a large difference in the service life of each part

Therefore, this mode of using one method for unified protection of boilers not only makes the enterprise a heavy burden, but also causes a great waste of natural resources and energy

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