Descaling of heat exchangers
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This post was last edited by w9970165 on 2011-6-24 11:22. When descaling the heat exchanger, use a high-pressure water gun. Is there any selectivity when using it to flush? Can both ends be flushed, or is it selective to flush one? Thanks
I heard a teacher named Ba from Harbin Engineering University say that high-frequency nuclear magnetic resonance can be used for descaling, but I don’t know whether it is true or not. NMR is used to change the molecular structure and then vibrate like ultrasonic waves for descaling. It is said that it is very effective when used on a 4-ton small boiler.
NMR decontamination is not yet widely used. Acid washing or high-pressure water or steam washing is used extensively. Choose one end and rush it~!
Some information says that the pressure of high-pressure water cleaning is 50-70MPa. Is this true?
You can use the corresponding descaling agent and then cycle.
Instead of descaling, it is best to treat it from the root to slow down the scaling. If washed with a high-pressure water gun, if the heat exchange tube is a fin tube, it will easily cause the fins to fall or be damaged. If the heat exchange tube is a plated tube, its coating will be easily damaged and its service life will be shortened.
Is the poster talking about a tube bundle heat exchanger? If it is, just flush it from one end, but the scale cannot be flushed away. You can try to use a mechanical method, that is, welding a brush to a long pipe and cleaning it manually. The effect is not very good and it is also very tiring. The best way is to pickle, use hydrochloric acid or oxalic acid, and add corrosion inhibitors, the effect is quite good.
The high-pressure water gun can play a role, but it is not completely clear. Generally, some evaporative cooling coils, such as evaporative cooling coils, use this method to descale.
Hard scales like calcium sulfate are very laborious to deal with mechanically. The effect of the loose scale layer on the surface is still more obvious. Chemical methods are often used, using acidic descaling liquid with corrosion inhibitors. However, the formula of the descaling liquid is selected according to the material, otherwise it is easy to corrode. Moreover, surface passivation treatment is required after pickling.
High-pressure water descaling requires good quality. Otherwise, operators usually work overnight. It’s a lot of work and boring. Just clean both ends. Haha, I was fooled 1