Cleaning method of boiler

Abstract

The invention provides a cleaning method of a boiler. The cleaning method comprises the steps of impurity removing, flushing, soda boiling, flushing, acid pickling, acid liquor jacking and draining and water flushing, rinsing and passivating. According to the cleaning method of the boiler, a soda boiling solution is utilized to react with oil stain on the inner wall of the boiler, the oil stain isthoroughly removed, the soda boiling solution does not contain inorganic phosphate, and the dirt discharge amount is reduced; acid is utilized to react with incrustation, copper scale and iron rust on the inner wall of the boiler in the acid pickling process, the incrustation and the iron rust on the inner walls of the boiler and a pipeline are dissolved, polyaspartic acid in an acid pickling solution has a good scale inhibition capability, and calcium salt can be effectively prevented from being generated; and etidronic acid has a dispersion effect, calcium and magnesium ions in water can bestabilized, on one hand, a corrosion inhibitor can effectively disperse and inhibit the scale, on the other hand, impurities are not introduced into a boiler system, and the dirt discharge amount ofboiler cleaning is reduced. According to the cleaning method of the boiler, a passivation solution is an organic passivation solution, chemical reaction can be generated on the passivation solution and the inner wall of the boiler to generate a passivating film, no ammonium ion is generated, and ammonia corrosion is prevented from being generated to the boiler.

Description

technical field [0001] The invention belongs to the field of boiler water treatment, and in particular relates to a boiler cleaning method. Background technique [0002] In daily industrial production, boiler water is continuously circulated and concentrated during use, and the mineral content in the water will continue to increase, which will cause scaling and oxygen corrosion on the furnace wall and fire tube. Once scale is formed on the fire tube of the furnace wall, the heat exchange efficiency will be greatly reduced, and the boiler will accelerate oxygen corrosion. 3+ , Fe 2+ state, while Fe 3+ , Fe 2 + , Fe, OH - The electrochemical corrosion between ions is more serious. If things go on like this, the service life of the boiler will be shortened and the safe production will be endangered. Therefore, the furnace wall fire tube of the boiler must be treated regularly. Common types of scale include carbonate scale, sulfate scale, silicate scale, mixed scale, iron...

AI Technical Summary

Problems solved by technology

The chemical cleaning of the boiler is a necessary measure to clean the heated inner surface of the boiler and prevent accidents caused by corrosion and scaling on the heated inner surface. It is also one of the effective measures to improve the thermal efficiency of the boiler and improve the water vapor quality of the unit; The high-temperature oxidized scale formed during rolling and processing, as well as the corrosion products, welding slag and mud sand and other dirt generated during storage, transportation and installation, ensure that the water and vapor quality of the unit is qualified as soon as possible after the unit is started; currently, cleaning for boilers The methods are different and the effect is not good. Due to the large amount of inorganic phosphate such as trisodium phosphate used in the cleaning process, the amount of sewage discharged during the cleaning is large, and the use of ammonia water to adjust the pH leads to changes in the solubility of ammonia water at different temperatures, resulting in local pH differences.