Chemical for cleaning boiler

Abstract

The invention relates to a chemical for cleaning a boiler, and belongs to the technical field of the chemical cleaning of equipment. The chemical comprises a corrosion-inhibiting acid-washing agent, a bleaching agent and a passivant, wherein the corrosion-inhibiting acid-washing agent consists of 1,3,5,7-tetraaza-adamantane, ethylenediamine tetracetic acid, hydrochloric acid, phosphoric acid, silicon fluoride, hydrazine hydrate, sodium silicate, cetyl dimethyl benzyl ammonium chloride, ammonium thiocyanate, sodium dodecyl benzene sulfonate and the balance of water; the bleaching agent is citric acid solution; and a passivant consists of ethidene diamine, formaldehyde, diammonium phosphate, hydrogen peroxide, sodium nitrite and the water. The chemical has stable chemical properties, low toxicity, a good sustained-release effect and high scale dissolving capacity, and does not have the damage of sour corrosion to the boiler.

Description

technical field [0001] The invention relates to chemical cleaning of equipment, in particular to a medicament for boiler cleaning. 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 oxide scal...

AI Technical Summary

Problems solved by technology

Domestic Shaanxi Chemical Design Institute uses pyrazolone drug by-product FAA colloid to make SH-405 citric acid pickling corrosion inhibitor, the performance is not stable enough, and the shelf life is short

Hydrochloric acid has a strong ability to dissolve iron oxides, but the corrosion inhibitors used for hydrochloric acid pickling require different corrosion inhibitors under different circumstances, which brings inconvenience to field application

[0005] The chemical cleaning and passivation process recommended by the widely used power industry standard "Guidelines for Chemical Cleaning of Boilers in Thermal Power Plants" (DL / T794-2001) generally has high passivation temperature, high energy consumption, long time, and even some passivation agents It is a carcinogen itself, and the environmental protection problem is prominent; especially the phosphate residue caused by the passivation of phosphate and polyphosphate is easy to cause acid corrosion, which will undoubtedly bring hidden dangers to the safe operation of the boiler in the future