Cleaning agent for flue dust scale on surface of gas heat exchanger of gas desulfurization system and preparation method thereof

Abstract

The invention discloses a cleaning agent for flue dust scale on the surface of a gas heat exchanger of a gas desulfurization system and a preparation method thereof. The cleaning agent is characterized by comprising the following components in percentage by mass: 5 to 25 percent of main cleaning agent, 3 to 15 percent of auxiliary cleaning agent, 2 to 10 percent of release agent, 2 to 8 percent of corrosion inhibitor, and the balance water, wherein the main cleaning agent is one or two of nitric acid, hydrochloric acid and sulfuric acid; the auxiliary cleaning agent is more than one of methanoic acid, acetic acid, ethylene diamine tetraacetic acid, sulfamic acid, glycollic acid, oxalic acid and hydroxyethylidene diphosphonic acid; the release agent is one of dodecyl dimethyl benzyl ammonium bromide, dodecyl dimethyl benzyl ammonium chloride and distearyl dimethyl ammonium chloride; and the corrosion inhibitor is pickling inhibitor. The cleaning agent can realize online cleaning at normal temperature, complete scale removal, short cleaning time, lower cleaning cost and no corrosion to enamel on the surface of a heat exchange element.

Description

technical field [0001] The invention relates to a cleaning agent, in particular to a cleaning agent for cleaning smoke and dust fouling on the surface of a gas-gas heat exchanger arranged in a limestone-gypsum desulfurization system in a large-scale electric coal-fired unit. Background technique [0002] Coal-fired power generation is still one of the main methods of power production in my country. At present, more than 90% of the limestone-gypsum desulfurization systems in my country's large-scale power coal-fired units are equipped with gas-gas heat exchangers (GGH for short). Whether the high-cost equipment outside the system is normal or not is related to the stable operation of the flue gas desulfurization system. In the desulfurization system that has been put into operation, after a period of use, problems such as serious fouling and blockage of GGH, poor heat transfer efficiency, and pressure difference far higher than the design value will occur, and the desulfurizat...

AI Technical Summary

Problems solved by technology

[0007] Among the above two methods, the ultra-high pressure hydraulic cleaning method has: 1) it may damage the surface enamel of the GGH heat exchange element; 2) there are potential safety hazards for the operator; 3) it cannot completely remove the GGH fouling; 4) the ability to reduce the differential pressure is limited, etc. shortcoming

The "two-step method" chemical cleaning method is relatively thorough, but there are: 1) The cleaning time is long, usually about 20 days; 2) The maintenance workload is heavy, and all GGH heat exchange elements need to be disassembled manually; 3) The process is cumbersome, Soda cooking requires steam heating; 4) Disadvantages such as high cleaning costs

It can be seen that the existing cleaning methods can no longer meet the needs of timely and effective cleaning of soot and dust on the surface of GGH