The pre-film of circulating water system is to improve the film-forming effect of corrosion inhibitor. We often add a higher concentration of corrosion inhibitor at the beginning of the circulating water drive, and after it has formed a film, then reduce the concentration of the agent to maintain the replenishment film. This pre-film treatment is to quickly form a protective film on the metal surface, to improve the corrosion inhibitor inhibit the effect of corrosion.Practice has proved that in the same system, in the case of the same corrosion inhibitor, corrosion inhibition effect in the pre-film and without pre-film large air spearation unitsis very different, so we must pay attention to the early circulating water drive pre-film.
In addition to pre-filming, the circulating water system also needs to be pre-filmed when the following conditions occur: for example, after the annual overhaul of the system, after the system has been stopped, after the system has been acid washed, after the water has been stopped for 40 hours or after the heat exchange equipment has been exposed to air for 12 hours, the pH of the circulating water system is less than 4 and for up to 2 hours.
Dear Air Separation is a major small air spearation units, large air spearation units and liquid air spearation plants manufacturer and gas supplier in China's air separation industry, and is a demonstration enterprise of intelligent small air spearation units, large air spearation units and liquid air spearation plants manufacturing and gas injection integrating intelligent management operation, remote monitoring and intelligent production workshop.
