Boiler membrane wall coating high-frequency remelting gas protection inhibition tube bundle oxidation process

Abstract

The invention provides a boiler membrane wall coating high-frequency remelting gas protection inhibition tube bundle oxidation process. The process is characterized in that in the high-frequency remelting process of a boiler membrane wall, along with the forward movement of a tube bundle relative to a high-frequency heating coil, nitrogen is adopted to isolate the interior of the tube bundle and the back side of the tube bundle from oxygen so as to inhibit scale generation. According to the process, the nitrogen is continuously blown into the tube bundle and to the back side of the tube bundleat a small flow rate, so that no scale is generated inside the tube bundle or on the back side of the tube bundle at a remelting high temperature, the potential risk of tube explosion caused by scalefalling is eliminated, and the fatigue life of the tube bundle base material is prolonged.

Description

Background technique [0001] With the accelerated implementation of the country's new energy development strategy, the domestic waste incineration power generation industry has developed rapidly in recent years. At present, the bottleneck problem that restricts the technical development of waste incineration power generation is that the membrane water wall of the boiler is severely corroded due to high temperature, and tube bursts occur frequently. In recent years, the International Center for Cancer Research has listed dioxin as a first-class human carcinogen. In order to prevent the secondary pollution of dioxin at low temperature during the waste incineration process, the newly designed national standard for biomass boilers has now made the boiler tube row temperature resistant The requirement is raised to 700°C, and the service life reaches more than 6 years. At present, although some TP347 stainless steel is directly used, the cost of TP347 stainless steel is not only hig...

AI Technical Summary

Problems solved by technology

[0006] (1) During the start-up and shutdown process of the boiler, because the impact scale of the high-pressure steam in the tube is easily pushed to the elbow by the water vapor, the steam circulation area there is reduced, and it is easy to cause local overheating, deformation and even tube explosion;

[0007] (2) The peeled scale debris will even be brought into the steam turbine by the steam, which will damage the flow parts of the steam turbine such as nozzles and cascades;

[0008] (3) The peeled scale debris may also cause the steam valve to jam, affecting the normal closing of the valve

[0009] The above problems will cause great hidden dangers to the safe and economical operation of garbage power generation units

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