Acid cleaning during the start-up of low-temperature methanol washing

I want to know too? This is the first time I’ve heard of pickling and alkali washing

When we were driving, the outlet pipe for the purified air was cleaned; the others weren’t cleaned

Will everyone respond actively? . It is generally used to protect coiled tube heat exchange equipment. Chemical cleaning must be carried out before driving. . That is, pickling, alkali washing, and water washing. . . What’s the result after pickling/for those who haven’t undergone chemical cleaning. How has it worked for you after you started using it?

There shouldn’t be a need for that, right? Washing with water is enough; acid or alkali washing is excessive

I don’t think acid or alkali cleaning is necessary, as the methanol cleaning process takes place at low temperatures, and the equipment used is made of low-temperature resistant stainless steel, which generally does not get oxidized into oxides and thus does not affect the heat exchange efficiency. Water cleaning is mainly used to remove welding slag left in the pipes; since low-temperature stainless steel is welded using TIG welding, the result is very clean. So I really don’t see any need for acid or alkali cleaning

This post was last edited by Lutao on 2010-1-2 at 15:32. Although TIG welding is used as the base process, slag still tends to form in the system. . . For example, when installing tray plates, repairs are carried out inside the tower; slag and welding flux residues may not be completely removed, and oil residues can also remain in some pipes. . . As a wash, it can only remove surface slag and rust, but it cannot completely clean the areas inside the tower that are covered in rust. . . For example, the material of Tower T1 is quite special, and it has embroidery on it.

4# Lutao: In the process of starting up a unit using methanol washing, aside from water washing, there is no acid washing nor alkali washing. After the water washing stage, it is sufficient to use a methanol-water separation tower or a methanol regeneration tower to increase the temperature of the water (usually, this temperature should not exceed the design temperature of the pipes in the hot area), and the results are very good； Secondly, it is important to note that during the actual construction and installation process, as the owner, it is essential to identify problems promptly and clear them up right away. During the actual drainage process, not many illegal items were found, and the water was very clean. However, after the methanol cycle was established, it was mainly this inlet filter that got clogged; cleaning it promptly was sufficient.

Acid washing and alkali washing are not necessary; as long as the air flow during purging is sufficient, and waste water is drained in a timely manner during water operation, the impurities in the system can be basically removed

Once the equipment pipelines are installed, the access hatches of the equipment are opened and cleaned, the pipelines are purged, and then a water wash is sufficient! Acid washing and alkali washing are not necessary, and even if there is welding slag inside the equipment pipes, acid washing and alkali washing may not be able to clean it completely! As far as I know, few manufacturers have actually carried out acid and alkali cleaning, yet their equipment is still performing very well! Of course, it would be even better if you could carry out pickling and alkaline cleaning; although weld slag cannot be completely removed, oil stains and rust can still be dealt with!