Chemical Resistance of piping materials 2

[Liefooghe]

We want to have a sprinklingsystem to be flusched with steam. In that sprinklingsystem we will add Sodium Hypochlorite and Bromine for bacteriacide.

My question is what kind of pipe material may we use? We would use Stainless Steel piping but what kind? The water is at 260-300 °F (Steam)

Are there good books where I can find which pipe material I can use when there is a sertain product at a certain temperature and with a certain concentrations going thrue the pipe.


With kind regards,

Jan Liefooghe

 

[c2sco]

Try searching Google with "corrosion guide" - gives a good few hits. One I think looks interesting is

http://www.cdcorrosion.com/corrosion_gb/html/jdc_telechargement.htm

Bromine is very nasty and eats through nearly anything when wet!
A guide I have suggests 316 is excellent for hypo, 304 is fair and 410, 416 and 430 is poor. I can't find where I got it from but E-mail me and I'll send it. Alas is doesn't mention hypobromites.
stuart.ord@process-notes.co.uk

 

[c2sco]

I've also found mention in a nice guide done by Wilden pumps. It only lists 316 under stainless steels, but reckons it is "B" ie "minor to moderate effect" to bromine water but "C" to 20% sodium hypochlorite solution ie "moderate to severe effect". The latter will be due to the chlorine of course. Seems the two references contradict here! You can probably still download this guide from

http://www.wildenpump.com,

or failing that I can E-mail a copy. Looks to me like PVDF is the best bet!

 

[saldanha]

You can also try the material handbooks

 

[bchoate]

bchoate
Are you using liquid bromine or are you using some bromine releasing material. Wet, liquid bromine is indeed nasty. It will destroy Hastelloy C-276. The only metal that stands up to true liquid bromine with water in it is tantalum. That is the reason that lined pipe is used for many of these services. But you have a temperature problem. PDVF is a good material for liquid bromine but the temperature is too high. PTFE lined pipe or glass lined pipe are the better choices if you are indeed using liquid bromine.
Bill C

 

[Liefooghe]

I've received a mail which states that SS 254 SMO is the best SS material which stands against bromine and hypochlorite.

 

[unclesyd]

Do you have tubercles in the system at the present?
If so the system is going to be very hard to sterilize without taking off all your paint. It is extremely hard to clean and sterilize a system once the bugs are in place and have made their condos. Tubercles are normally very good insulators and you have to use long exposures for sterilization. It is also hard to clean and treat a system like a sprinkler system due to all the nooks and crannies where the bugs can hide. If you can’t sterilize with steam any chemical treatment of the water will probably be ineffective if tubercles are present.

Before you try this yourself get with a CTW treatment company as they have experience with using both these treatments. They also have the chemicals needed.

Another approach would be to talk to one of the larger water well drilling companies as they routinely treat systems with chlorine gas. They probably want treat a system such as yours but may be able to give some pointers.

If you are try to keeping the bacteria count low in a clean static system you might talk to supplier of film forming materials using a bactericide, like the QA salts. One company is Cortec.

 

[Liefooghe]

The firesystem is cleaned with steam. I'm sure that tubercles will be present.

254 SMO is a material which is simmilar to Hasalloy but a bit cheaper.

A other possibility is dubble walled piping system. CS pipes with teflon or PTFE.