Sulfuric Acid Pipeline
Sulfuric Acid Pipeline
(OP)
Hi you all,
I'm currently involved in the design of a 5 km 6" pipeline that transports 98-99% wt. sulfuric acid.
I'm interesting to know what codes/standards are applicable to the design of such a system and what are the best practices to follow for specific issues related to operation, inspection, maintenance etc.
I'm currently involved in the design of a 5 km 6" pipeline that transports 98-99% wt. sulfuric acid.
I'm interesting to know what codes/standards are applicable to the design of such a system and what are the best practices to follow for specific issues related to operation, inspection, maintenance etc.





RE: Sulfuric Acid Pipeline
First, follow the general operating practices for pipelines.
Which specific issues?
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"The problem isn't finding the solution, its trying to get to the real question." BigInch
http://virtualpipeline.spaces.live.com/
RE: Sulfuric Acid Pipeline
I'm a petroleum guy too, and I've built quite a few oil and gas pipelines with ANSI and other oil standars/practices.
The "specific issues" I'm trying to get a reply are:
1. Should the PL be burried or installed aboveground (for better inspection etc.)?
2. What kind of leak detection system applies better for each installation (burried of aboveground)?
3. What kind of corrosion monitoring applies better to a sulfuric acid PL?
4. Should the PL designed for pigging or not (I assume water is used to push the pig during PL inspection)
These issues are not covered by ANSI. Hope you got an idea of what I'm looking for.
Thanks anyway.
RE: Sulfuric Acid Pipeline
My experience with your application is limited, however a huge red flag popped up when I read your issue number 4.
Very, very carefully review using water for testing, pigging, etc. in an acid line. If you must, make sure the piping (especially low points) can be drained and thoroughly dried, and VERIFIED that it's dry before introducing acid.
Regards,
donf
RE: Sulfuric Acid Pipeline
RE: Sulfuric Acid Pipeline
**********************
"The problem isn't finding the solution, its trying to get to the real question." BigInch
http://virtualpipeline.spaces.live.com/
RE: Sulfuric Acid Pipeline
I'm not running acid pipelines either. That's why I'm looking for best practices and BATs. I would not just rely on intuition and experience alone when it comes to safety.
RE: Sulfuric Acid Pipeline
**********************
"The problem isn't finding the solution, its trying to get to the real question." BigInch
http://virtualpipeline.spaces.live.com/
RE: Sulfuric Acid Pipeline
Above ground is the way to go. Small leaks can be detected easily and quickly. Below ground they could leak for some time and create weak acid around the pipeline resulting in major failure.
Normal thickness readings and periodic Xray should provide good data on life time and predictive maintenance.
RE: Sulfuric Acid Pipeline
**********************
"The problem isn't finding the solution, its trying to get to the real question." BigInch
http://virtualpipeline.spaces.live.com/
RE: Sulfuric Acid Pipeline
As stated above water is a NO/NO as it will cause horrendous corrosion while it dilute the acid and will dissolve the Iron sulphate film that provides the major corrosion protection against the H2SO4. Inhibited water is not the answer.
The is a a major problem with O2 corrosion or grooving in the top quadrant of the pipe. As mentioned above this is usually monitored by RT. Normally in smaller lines provisions are made for rolling the line 180° to mediate the effect of the groove.
Velocity has to be controlled.
Heat input has to be controlled as well as freeze protection.
Slope of the line has to taken into account for draining the line.
There is a possibility of having to have a N2 purge.
If there are people you might have to consider double containment.
Tankage at both ends has to have all the right stuff.
RE: Sulfuric Acid Pipeline
Keith Cress
kcress - http://www.flaminsystems.com
RE: Sulfuric Acid Pipeline
If buried leak detection can be monitored by use of tracer wire. But by the time it leaks you will know because your custody transfer flow meters will be showing a discrepancy.
Those acid lines I have been exposed to were equipped with pigging facilities. Pigs were N2 driven.
Station facilities need specialised equipment to be able to maintain them. This includes peristaltic pumps to be able to empty at low points.
Orica (nee ICI) published design guides for handling the fluid in Australia. Check with your material supplier and you will be surprised the amount of information they can provide. Also try and inspect some existing facilities.
Vopak operate acid shipunloading lines.
RE: Sulfuric Acid Pipeline
I am having a lot of trouble understanding how this pipeline makes any sense. When sulfuric acid moves, it can erode/corrode carbon steels rapidly
What material do you intend to use for this pipeline ?
If the answer is carbon steel, how long do you expect it to last ? (and what type of corrosion allowance are you using ?)
You see, I have seen a lot of small bore stainless piping systems in process plants... especially in applications where the acid velocity is 5-12 fps.
Where I have seen carbon steel used for sulfuric acid service the velocity is much lower (2-5 fps) and a 0.125 inch corrosion allowance is used.
So as I see it, your choices are large diameter, thick walled CS or expensive SS....
Wouldn't it be cheaper to use tankers to transfer the acid ?
-MJC
RE: Sulfuric Acid Pipeline
Zicor is expensive but is too resistant to the corrosion.
maybe you can use PVRF too.
If money isn't a problem, i prefer use a zicor pipe with a second container in 316SS with a preassure swicht for leak deteccion like the mass flowmeters. This is the requeriments sugested by the standars.
I'm using zicor pipes for acid sulfuric in 99,98 and 93% in a zinc plant.
sorry, my english is bad at this moment.
RE: Sulfuric Acid Pipeline
Do you mean the material "ZeCor-Z"..????
I believe that ZICOR is a popular medication in the USA for nasal problems or heart attacks or something.
?????
-MJC
RE: Sulfuric Acid Pipeline
Zicor in spanish. zecor in english.
Is a SS with a low charge of silice.
Best regards.
RE: Sulfuric Acid Pipeline
At ambient temperatures you can either use carbon steel with a large corrosion allowance and VERY low velocities, or ordinary austenitic stainless steels.
For a buried line, unless the size is huge I would imagine stainless would be the choice.
RE: Sulfuric Acid Pipeline
I agree...
But that sounds a lot like what I suggested ?
Then, you have to ask yourself, will a stainless steel pipeline of this length make economic sense....
-MJC
RE: Sulfuric Acid Pipeline