Mobile VACOM heat exchanger cleaning method and device

Abstract

The invention discloses a mobile VACOM heat exchanger cleaning method and device. A cleaning circulating system is formed by a mobile car; the temperature and the concentration of cleaning liquid filled with a sulfamic acid solid chemical cleaning agent are controlled; then, a corrosion inhibitor with a certain concentration is added to control the cleaning flowing speed of a heat exchanger; the dipping cleaning is performed; and the operation from circular cleaning to drainage is performed until the pH is higher than 7. The device comprises a mobile cleaning box; a medicine distribution portis formed in the cleaning box; a discharge pipe and a water inlet pipe communicating to a medicine distribution box are arranged on the side wall of the cleaning box; a stirrer, and a liquid inlet pipe, a recirculation pipe and a liquid return pipe communicating to a heat pre-exchanger are arranged in the cleaning box; the cleaning box is provided with a temperature meter and a magnetic overturning plate liquid level meter; and the heat pre-exchanger is provided with a refrigerant port and a heat medium port. The device can effectively solve the problem of system operation stop caused by scaling of the heat exchanger, and improves the system operation effectiveness, safety and economy.

Description

technical field [0001] The invention relates to a preheater cleaning device for a coal-fired unit, in particular to a mobile VACOM preheater cleaning method and device. Background technique [0002] For 1000MW coal-fired units, the zero discharge process of desulfurization wastewater adopts VACOM's evaporation concentration crystallization technology. It mainly includes four units including pretreatment, brine concentration, crystallization and solid waste disposal. The pre-heat exchanger conducts heat exchange to raise the temperature of the effluent of the pretreatment system. [0003] Because the pretreatment system effluent contains calcium, magnesium, iron and other ions. The above ions will form corresponding calcium salts, magnesium salts, and iron salts in water, such as CaCO 3 , Ca(HCO 3 ) 2 , CaSO 4 , Mg(HCO 3 ) 2 , MgCO 3 , MgSO 4 , Mg(OH) 2 Wait. Calcium salts are the main ingredient causing fouling in heat exchangers. After magnesium is dissolved in...

AI Technical Summary

Problems solved by technology

[0004] The thickness of calcium and magnesium scale increases, and the thermal resistance of the heat exchanger increases significantly, resulting in a significant decrease in heat transfer efficiency; after scaling, the flow area of ​​the fluid decreases, resulting in equipment blockage and increased energy consumption of the pump; scale layer Deposition on the heat exchange surface is also prone to hot spot corrosion under the scale, which will perforate the heat exchange surface, endanger the safety of equipment, and easily cause accidents

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