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sulfuric acid (98 % concentration) and piping for pump

Please advise the piping material at the discharge of pump to dose the concentrated sulfuric acid (98 %)in cooling towers.

M. Irshad
Refinery - Rwp.
2005

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2005

Why use such concentrated acid for pH adjustment?
Inside, you could use appropriate vinyl tubing or PVC pipe.PVC ages quite rapidly in sunlight and would require extra plasticizers in the material. Stainless, even 316L does not like dilute sulfuric above 75 F, but I have no idea on how it would perform with concentrated.
Teflon tubing would be a good way to go if it were well supported.

James Watts
- Navarre, Florida

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2005

Hi M.I.

Have a look-see at # 8698

Mild steel would be OK WERE the concentration kept VERY HIGH and not get 'diluted' with ordinary air whereby the it gets to become diluted as it absorbs moisture from the air = mega aggressive.

PVC should be ideal ... but the plasticized 'vinyl' tubing would soon 'harden' up as the plasticizers are removed. This applies, of course, to highly concentrated H2S04.

Ptfe tubing would be OK, so would PVDF.

I'd keep it simple and use rigid Sch. 80 PVC.

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).

I advise reconsidering your choice of acid of this concentration on safety reasons alone. I have worked with this one for years and appreciate the speed it attacks skin. It is not as forgiving as the 93% grade.

James Chunn
- Theodore, Alabama
2006