Environment Protection +Any way of hydrotesting without glycol ? 2

[Hansito]

Dear coleagues,
We are planing to reduce the environmental issues related to freezing weather hydrotesting using glycol.

One idea considered was to run steam through the pipe over the night but in fact, steam consuming is also an environment issue. Other idea was trying to use the the day allowing window and use fresh water, but as everybody knows that would be very difficult to achieve.

Please if anyone knows any procedure or alternative which could been considerated less agressive to environment, let me know.

Regards,
Hansito

 

[GregLamberson]

Hansito

Is your pipe/pipeline UG or AG? What is the ambient temperature? What's the duration of your hydro test?

Is heat tracing feasible as an alternative?

Greg Lamberson, BS, MBA
Consultant - Upstream Energy
Website:

http://www.oil-gas-consulting.com

 

[BigInch]

Can you spray water ON the pipe?

**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

http://virtualpipeline.spaces.live.com/

 

[btrueblood]

Other options, with varying degrees of environmental and safety issues of their own:

- propylene glycol and water
- brine
- ethyl alcohol/water

 

[zdas04]

I would do the stress calcs to see if you can do a pneumatic test. Hate to start this discussion again, but if the alternative is to try to dispose of a large volume of glycol, brine, or alcohol I'd sure do the calcs.

Biggest problem with any sort of test where you're worrying about freezing water is brittle failure. Remember the Space Shuttle Challenger? Low temperature tests are amazingly high risk. I've got some pictures from the literature of a 5-inch wall thickness vessel coming apart violently during a low temperature hydro test. Above 50F the vessel would have been fine at the test pressure.

David

 

[dcasto]

second that zdas04 opinion.

 

[Apakrat]

In addition to the questions above by GregLamberson and BigInch, what is the piping length, size specs, and required test pressure?

Have personally witnessed the pipe failure results of an 20 mile 14 inch pipeline at 250 psi air, and an 11 mile 20 inch pipeline at 1500 psi with segment bubbles containing water compressed the air occurring after 10 prior pipeline yield test failures.

Neither were pretty and panties had to be changed after both incidents.


At 74th year working on IR-One2 PhD from UHK - - -

 

[Hansito]

L&G:
Thanks for the responses received and regarding to additional data referred, the following is what I coud Get:

Piping Lenght is 300 meters
Size 14 inch STD
Specs Carbon Steel
Test Pressure 15 bar g
ambient temperature = -15 C

The pipe is AG, as far as we understand UG piping should have normally no freezing problems.

Heat tracing is not considered as an alternative unless there is any possiblity of doing with some kind of electrical rental device.

Pneumatic test are highly avoided by the client due safety reasons. Environment is not over the safety in this case.

We have gaps of "normal" ambient temperature during the day. But we can not assure not having water inside during the night if we try it. The main concern with water is: since water expands when passing from liquid to solid phase internal valve parts (even we have it open for test) and pipe could be damaged.

Thanks again and I will appreciate if the extra data generate new good comments like the present ones.

Regards,
Hansito

 

[stanweld]

Is your piping seamless or welded? Has it been impact tested? Have you calculated the stress in hoop at the test pressure? Have you calculated the stress ratio to the specified minimum yield strength. Without performing the calculations myself, they are estimated to be below 30% of the SMYS. Pneumatic testing should be considered if the pipe is new and seamless. Safety precautions must be addressed if pneumatic testing is proposed.

The length and volume of pipe is not considered too great that the use of a recirculating boiler to heat the pipe should not be considered if hydrotesting is performed.

 

[Unotec]

BTW, two threads on the same subject in different forums is frowned upon on these parts.

<<A good friend will bail you out of jail, but a true friend
will be sitting beside you saying ” Damn that was fun!” - Unknown>>

 

[Apakrat]

Back in my youth, 15 bar g, (217.55 psi), on a 14 inch OD pipe, would be considered a leak test. Human safety is still a concern then, as was environmental, long before invention of the EPA by the flannel mouth bass.

Visually inspect the 300 meters of piping for any rusty pitting.

Propose "Testing" for consideration

1. Clean fueled, open flame, smudge pot, warming arrangement while doing a clean water hydraulic pressure test.

2. Leak test procedure by running a vacuum test. If and when the vacuum will not hold, low psi pneumatic test using air with an additive which can be located using an appropriate "Sniffer"to find and repair.


At 74th year working on IR-One2 PhD from UHK - - -

 

[BigInch]

Is anybody going to ask what code this is?
OK, I will.
What code will this test be under?

**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

http://virtualpipeline.spaces.live.com/

 

[Hansito]

Thanks everybody for the answers.
Regarding to questions:

The code is B31.3. I forgot to mention, in fact, the main concern is water from liquid to solid expanding inside the piping.

Regarding to calculation done. We have made all the normal calculation, but the models do no includes the effectos of water inside expandig from liquid to solid. It don't seems easy to model.

Regards,
Hansito

 

[BigInch]

There's no point about modeling near freeze water, the pipe will burst unless its gun barrel, then there's still a chance.

No vacuum / sniffer test provisions in B31.3

**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

http://virtualpipeline.spaces.live.com/

 

[Hansito]

Thanks biginch

 

[Cuemaster64]

Hansito,

Two questions come to mind. Do you not want to use any form of glycol due to the final process to be fed through your line for fear of any contamination? My quick calculations show that you will only require around 30 cubic meters of test fluid. Do you not have a supplier that can service your needs readily? eg. Bringing a tanker trailer in to fill and test and then vacuum suck it out again. We use propolyene glycol mix here all throughout the year (Ft. McMurray) but as others have stated we do not do any testing below minus 29 celcius for fear of brittle fracture.

As always these are my thoughts and not those of my company.

 

[btrueblood]

Sorry not to be clearer in my earlier post. In addition to what others have written,

1. there should be minimal disposal issues with water mixes containing either propylene glycol, ethyl alcohol, or salts (brine). I know we can dipose of several thousands of gallons at a time in our municipal sewer here. But, that is propylene glycol, not ethylene glycol which is toxic and a disposal rat's nest.

2. There are minimal safety/toxicity/handling issues with any of the 1st three, alcohol being the worst of them, and hey, people like me drink the stuff every day.