Piping materials for Dilute CLO2

Aluminum is compatable with Chlorine Dioxide.

Yes Ace Boeringa, you are right, but the corrosion rate of Chlorine Dioxide with Aluminium (at 10 ^oC & 100% concentration) reaches 508 micron/year.

Also, I think the Titanium is compatible with Chlorine Dioxide since its corrosion rate (at 93 ^oC & 20% concentration) reaches 50 micron/year.

Note. The prescribed data was extracted from NACE code, Corrosion Data Survey, Metals Section-Sixth Edition (Pages 34 & 35).

Abdel is also correct. Price and availability of aluminum is more attractive than that of titanium. Also the stated concentration is 0.2%

Yes Ace Boeringa,

I agree you.

does fiberglass pipe works?

Sure, fiberglass pipes can work correctly with chlorine dioxide, but till now I have no reference.

You have to make a lap check for fiberglass to withstand the corrosion of chlorine dioxide and check for any changes after 7 and 21 days. Otherwise, wait for additional assistance from CR4 members.

There are potential issues with delamination along this length, in accordance to whatever layup you use.

This are the only materials for which the Corrosion Rate is below 2 mpy (0.05 mm/y). The data are taken from Corsur of NACE (knovel).

There are many others materials with Corrosion Rate below 20 mpy (0.5 mm/y).

hope this help

S

Corrosion Control & Corrosion Protection

mpy = Mils per year

1 Mils = 0.001 inch = 25.4 micron = (25.4/1000) mm

If CPVC will work then why not run it or Kynar in a larger pipe made of stainless or carbon steel to support and/or protect it? I have done this many times on acid lines and it works very well. you do leave the ells exposed but with some planning on the routing the danger of them being damaged is small. Also you could use titanium for the exposed ells and the CPVC run inside a sheath of steel pipe on the longer straight runs. This could make more chances of a leak because of the flanges/gaskets though but it would be allot cheaper to do this way. I am not sure what your layout is but when I do this I try to run it in an area that is out of harms way from being damaged or having contact with people. I am sure that the main thing is safety with this system and you may not want to take any chances of having a leak. In this case the titanium pipe would be the best I think because all of the flanges associated with the Kynar lined pipe.

pipewelder

Thanks to all for responses and suggestions. After some debate, and considering costs, risks, 'comfort factor' with the materials and experience with assembly, we've chosen to stick with Kynar-lined carbon steel. We only have one welder that can weld Titanium with any skill, and the local crews have built a bunch of Kynar-lined pipe the last couple years. Some other options we looked into were 254-SMO, but the material costs were way out of line ($80/foot for 1.5"!). I'll follow up when we're done with final costs per foot of installed pipe, in case this comes up for anyone else in the near future.

Scott

CPVC lined (bonded) FRP armored (makes very rugged) is an excellent solution.

FRP by itself will do the job (using a premium vinyl ester corrosion resin).

Let me know if you need a quotation. I am Canada.