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Change from Trico to what

 

We want to change from degreasing fabricated metal components & pipes from an open hot trico tank bath to something more environmentally friendly (& user friendly) can anyone suggest a good alternative please?

JimStott
- Lancashire, England

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Well, the first step could be to switch to a closed trico bath. Beyond that, you would need to decide whether to switch to a more acceptable (but much more expensive) solvent like n-propyl bromide or whether aqueous cleaning could work for you.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
 

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There are now numerous replacements for trichloroethane and trichloroethylene degreasers. ( By trico, I suppose you do mean chlorinated organic solvents). Both tricholoroethylene and trichloroethane have now been cited as possible carcinogens and have had their OES and MELs adjusted accordingly. They are also cited as being environmentally non-friendly. Depending on your reason for changing, there are various alternatives. If you want to stay with chlorinated solvents, there is always tetrachloroethane and tetrachloroethylene or even percholoroethane, but these too may have problems.

Alternatives, but similar solvents include brominated organics that can be readily supplied in the UK. Further alternatives include aqueous washing systems with and without ultrasonics. These systems have improved no end over the past few years and should be seriously considered. One quite esoteric system is to use solid carbon dioxide, but I don't know much about the availability of this in the UK However, be aware there is no direct replacement for a solvent like tricholoroethane and you will have to modify your degreasing procedure. As to suppliers, I would talk to your current solvent source, as they will know the details of what will suite your needs, or ask the IMF or MFA or any other relevant trade association.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK