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Reaction of Sulphamic Acid

Hello

I am trainee Engineer in an industry, I want to know about chemical reactions takes place during de-scaling of cooling & heating water systems; please inform me what type of gases and by-products form during reaction and how we do this safely?

Faisal Murad
Student - KSA
January 31, 2008

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Highly diluted sulfamic acid ⇦ this on eBay or Amazon [affil links] is used in common household metal polishes and might be of little concern, whereas highly concentrated sulphamic acid offers all sorts of dangers. You cannot receive safety instruction over the internet but absolutely must have hands-on training for any dangerous chemicals you work with. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
January 31, 2008

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First of two simultaneous responses -- February 2, 2008

Hello Faisal Murad,
mainly CO2 (i.e., carbon dioxide) and small quantities of other gases hydrogen including. In some cases very small quantities of sulfur derivates even H2S. All those gases are dangerous in higher concentration.

Be careful.

Janusz LABEDZ
Aurotech - Warsaw, Poland

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Second of two simultaneous responses --

Besides what Ted told you, most chemical reactions to remove scale and will liberate hydrogen, metallic salts and dissolved metal in acid. Less dangerous acid to handle would be citric acid ⇦ this on eBay or Amazon [affil links] . Hydrochloric would be faster and also less dangerous to personnel but maybe not so for the metal you want to clean. Aluminum is an example of a metal heavily attacked by HCl, whereas copper is almost immune.

Guillermo Marrufo
Monterrey, NL, Mexico
February 2, 2008