Cooling water scale is mainly calcium carbonate scale, the chemical reaction of its generation process for calcium carbonate and carbon dioxide, water to generate calcium bicarbonate reversible reaction. Today by gnee small editor to tell you condenser purple copper tube carbon dioxide chemical cleaning method, I hope to be able to help you.
To the cooling water into the CO2, you can make the concentration of CO2 in the water increases, so that the chemical balance to generate calcium bicarbonate direction to move, to stop the formation of scale.
Carbon dioxide method has some of the following conditions of restriction: a. To have cheap Co2 available; b. Can only be used for closed indirect water-cooled equipment (such as column tube or casing type cooling equipment), should not be used for pneumatic condenser or drenching type row of pipe cooler, this is to prevent the addition of cooling water into the Co2 re-dispersal to the atmosphere and failure; c. Circulating cooling water carbonate hardness is less than 7?8 [H +] mmol/L; d. CO2 in water tends to cause corrosion of metal equipment in the cooling water system. For these reasons, the CO2 method has not been widely used in cooling water systems.
Advantages of chemical cleaning are: no need to dismantle the equipment; can be cleaned to the place where mechanical cleaning can not; chemical cleaning uniform - consistent, small gaps can be washed, and will not be left with the deposition of particles, the formation of the core of the new scale; can be avoided to avoid the damage of the metal surface; rust and passivation treatment after the cleaning can be prevented from rusting; chemical cleaning can be completed at the scene, the intensity of labor is less than the mechanical cleaning. Less labor-intensive than mechanical cleaning.
The disadvantages are: when the heat exchanger's tube and shell processes are all clogged with dirt, it is impossible to use chemical淸; because of the use of various chemicals, the waste liquid of the淸 needs to be processed; it is difficult to remove carbon fouling; steel corrosion is inhibited by the addition of corrosion inhibitors, but if the selection of corrosion inhibitors and the use of the wrong conditions, corrosion phenomena will occur. Usually in the case of mechanical cleaning does not work, the use of chemical cleaning of heat exchangers.
