Hydrogen Peroxide 7

[Liefooghe]

Hello,

A pipe system is filled with Hydrogen peroxide.
When in a pipeline which ends with a valve and the valve is closed and there remains a little bit of Hydrogen peroxide, What happens when in the summer the peroxide in the pipe heats up from 68°F (ambient) to 104°F (summer).
Will it expand? How much and what are the measurements that we need to take care on the valve?

With kind regars,

Lantyr

 

[Latexman]

Lantyr,

First, H2O2 is not your common, everyday chemical. It is continuously decomposing! Depending on the concentration you are using, there are special valve and piping specifications that must be followed to have a safe and explosion-free installation. Of particular concern, is anywhere H2O2 can be confined, like in the ball of a closed ball valve. I recommend asking your H2O2 supplier for their H2O2 design manual or guidelines. I've used FMC's and have never had a problem. Better yet, they may do the work for you!

Back to your question. It will expand, and it will decompose. If you don't provide adequate relief, your ball valves will explode and the piping may too. Contact your supplier.


Good luck,
Latexman

 

[hacksaw]

who did your piping design?

 

[Liefooghe]

Jacobs Engineering group did the piping design

 

[Latexman]

What's the concentration of your H2O2? I'm most familiar with about 35%.


Good luck,
Latexman

 

[BenThayer]

I agree with Latexman's recommendation to contact your supplier.

Solvay has helped us in the past. The suppliers can be quite helpful. Solvay's design guide specifically states that you should not have a length of pipe with two block valves unless you have a relief between them.

They actually give rules of thumb that for a 1/2" inlet PSV, it can protect X feet of 1" pipe or Y feet of 2" pipe, etc.

Another useful site is

http://www.h2o2.com/

You should be using valves specifically designed and cleaned for h2o2 also. I think Jamesbury makes special ball valves that have drilled balls similar to chlorine valves.

As was said, H2O2 is always decomposing. Now we need to talk about how fast. It is related to surface area and the general rules of thumb are generally referring to drums. The area to volume ratio in a pipe is much greater than a drum. I am surprised you have not had an incident. You may have some packing leaks.

 

[Montemayor]

Good, experienced input from Latexman & BenThayer! This is not an application for beginners or "fast learners".

Drilled ball valves have been used with success - but I would only follow the recommendations of the Peroxide supplier as to make, model, and materials of construction. As hacksaw infers, Jacobs probably did all the engineering in the expert and classical manner. But I would make sure, if it was my plant.

Everytime I've done H2O2 projects, I've never rested until I've checked (& had peers check) every calculation and personally walked down every foot of installed piping and valving. No stone was left unturned PRIOR to the detailed Hazop. I presume all SS has been treated and pacified.

Art Montemayor
Spring, TX

 

[Montemayor]

All:

I'm going to add this footnote as a reminder to us all of what we are dealing with when we handle Hydrogen Peroxide. I failed to mention this historical piece of evidence that I now remember and just want to make sure it is not repeated:

Remember the August 2000 incident that caused the destruction of the Russian submarine "Kursk" and the death of all its crew. This tragedy was studied and investigated and found to be caused by the Peroxide oxidizer that was used in the Russian torpedos as a fuel accelerator. This method was well known to USA and British submariners, but had been scrapped because of the risks involved in a Peroxide leak inside a sub. The Kursk incident proved the Americans and British to be correct in their risk analysis and pointed directly to the importance of knowing everything there is to know about Peroxide and its handling.

Art Montemayor
Spring, TX

 

[unclesyd]

Art,
The British had an accident (dockside) with almost an almost identical designed torpedo that killed several submariners several years prior to the Kursk.

Another anecdote about H2O2. When I was a CO-OP we used 35% H2O2 to precipitate iron from an acid bath. The supplier shipped us 70% (4 5# bottles) by mistake. It so happened that while these bottles were sitting in the store room awaiting disposition we were inspected by the City Fire Marshall. The gentleman had a heart attack on the spot. He did survive and after he recovered slightly at the hospital his first words were did we get rid of H2O2 yet.

 

[Montemayor]

unclesyd:

Thanks for your support in stressing the dangers surrounding the handling of Hydrogen Peroxide. I believe it was the British submarine, Sidon, which sank in 1955 and 13 sailors were lost. If I'm correct, if was shortly after this tragedy that the USA and Britain swore off the idea of employing more potent torpedoes at the risk of using Peroxide. The trade off was judged as not being worth it.

I hope that young engineers reading this don't get the impression that we are using "scare" tactics or laughing off a dangerous situation. I think it is all our intent to draw a clear and accurate picture of the risks involved and that an engineer should be well versed and trained prior to designing and handling a Hydrogen Peroxide application. It can be done very efficiently and safely - if one takes all the precautions and safety guidelines that come with the territory. The more experience and knowledgeable background in the chemistry involved, the safer and surer the design and operation.

Art Montemayor
Spring, TX

 

[hacksaw]

I think were all agreed about the hazards, but the issue that confounds me is that presumably a qualified piping design standard had been used. That does not appear to be the case.

 

[moltenmetal]

Proper design guidance for handling hydrogen peroxideis important and I do not intend to minimize that point. But the guidance and requirements are very different for handling the 75%+ peroxide used in military weapons than they are for 35% or even 50% peroxide- these concentrations are handled daily in the water treatment business.

The best source of guidance for handling these materials is the people who make them. Have a look at Degussa's website as a starting point.

 

[Stresfree1]

I agree with the advice to talk to your supplier. Get an expert to review the system, all materials of construction, and cleaning/passivating procedures before any H2O2 goes in.

I just designed a system to handle 70% H2O2. The supplier was FMC. FMC provided a really good, extensive design manual as well as actively reviewing our pipe specs, equipment specs, P&ID's, and participated in the HAZOP. They were a lot of help and caught problems we never would have.

FMC also contracted with us to do the cleaning and passivating.

We worked with them a lot to minimize the number of valves. Ball valves had the vent hole drilled. Every line that could be closed in had a safety valve on it. Clean, clean, clean.

 

[BenThayer]

Just a quick note that if you want to see what happens if no relief is used, check out the photo in the website below.

http://www.aiche.org/ccps/pdf/beacon0303.pdf

sort of the old picture worth a 10^3 words

 

[zdas04]

The guy that taught me about H2O2 stressed that drilling the balls in ball valves may not be enough. His recomendation was trunnion ball valves (cleaned and passivated) with a PSV on the vent hole. He had used this technique for 20+ years without a valve coming apart, but had had a lot of PSV's lift in shut ball valves.

This is really difficult stuff (which is why it gets used so often, the characteristics that make it difficult to transport/store make it very useful in many reactions) that requires extreme care in design and operating procedures with zero tolerance for short cuts.

David Simpson, PE
MuleShoe Engineering

http://www.muleshoe-eng.com

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