A surface-active amine preservative for thermal power plant boiler shutdown protection

Abstract

The invention relates to a surface active amine corrosion inhibitor for boiler shutdown protection in a heat-engine plant. Each litre of the surface active amine corrosion inhibitor contains 1-5mg of hydrazine, 100-500mu g of ethanolamine, 10-100mu g of hexamethylene tetramine, 1-10mg of N-(2-amino ethyl) morpholine, 20-200mu g of pyrazine and 50-500mu g of piperazine; ammonia water is used to regulate the pH value to 9.3-9.7; and the solvent of the surface active amine corrosion inhibitor is desalted water or deionized water. Compared with the prior art, the surface active amine corrosion inhibitor prepared according to the invention has good protection effect on a boiler and steam turbine high / low-temperature equipment during the shutdown period, and the negative effects that a samplingtube is blocked, resin precision processing performance can not be influenced, starting and flushing time is long, the corrosion inhibitor deposits on the surface of the low-temperature equipment fora long term and is slowly released and the like are not generated.

Description

technical field [0001] The invention relates to a surface active agent, in particular to a surface active amine preservative used for the outage protection of boilers in thermal power plants. It is mainly used for surface active amine anticorrosion treatment for supercritical and air-cooled unit boilers in power plants and steam turbine high / low temperature equipment shutdown protection for water vapor side. Background technique [0002] If the boilers in thermal power plants are not protected during shutdown, the boilers and steam turbine equipment will be corroded. When the boiler is started, it will affect the quality of the water-steam system, cause the deposition of corrosion products on the heating surface and affect the heat exchange efficiency of the unit, and even deposit on the blade surface of the steam turbine to reduce the output of the steam turbine, which greatly affects the safe and stable operation of thermal power plant equipment . Therefore, thermal powe...

AI Technical Summary

Problems solved by technology

Due to the high freezing point of ODA, low solubility in water and high viscosity, its poor dispersion in water will cause it to block the sampling pipe of the thermal instrument, which will affect the water quality monitoring work during the start-up process of the unit; It has an irreversible impact on quality. After pollution, the strength of the resin is reduced, it is easy to break, the sedimentation characteristics change, and it is not easy to recover and analyze, thus affecting the stable operation of the fine treatment. Due to the influence of ODA on the mixed bed resin, it is usually required to control the water when the unit starts and stops. The ODA content is less than 0.5mg / L before the fine treatment can be put into operation, which greatly weakens the purification effect of the condensate fine treatment system during the start-up and shutdown of the unit, and increases the risk of corrosion and scaling of the unit; due to the large area of ​​the air-cooling island, the temperature of the system is low , ODA has a large amount of adsorption and deposition in it, and it is difficult to completely carry it away in a short period of time during the start-up and operation of the unit, so that compared with the water-cooled unit, the ODA content in the existing water decreases slower, and the time for fine treatment is longer Hysteresis, and at the same time make the water quality poor for a long time after the unit starts