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Leaking natural gas storage

Leaking natural gas storage

Leaking natural gas storage

(OP)
Let's say I have a gas storage field; it's an old oil well being used for natural gas storage. And I skimped on the valve at the base of the casing to shut it off if the casing cracks or the cementing fails. Why would the well head not have a way to divert the gas to another well? It's presently leaking like 12,000 tons of gas per day; drop in the bucket and all.

Seriously, there was a way to pump gas into the well. Why is there no way/place to pump the gas back out?

RE: Leaking natural gas storage

As been shown in both the BP Deepwater Horizon disaster and the more recent Southern California Gas Porter Ranch leak, there are alternatives, but they usually involve drilling a completely new bore to the leaking bore to seal it and the new bore, a non-trivial effort.

The reason that there's no other path is that it was likely sealed, or is the leaking path.

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RE: Leaking natural gas storage

I'm missing the point here. What has the wellhead got to do with downhole casing leak?

And when did gas start to get measured in tons?. 12000 per day doesn't sound negligible to me.

Storage pressure makes the gas flow back

Very vague details here so rather vague answers....

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Leaking natural gas storage

First if gas is leaking out then something (water) is leaking in.
These storage facilities weren't designed to handle that sort of issue.
Porter Ranch is a real winner, leaking like mad in a residential area.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

RE: Leaking natural gas storage

(OP)
Littleinch - I likely have the terminology wrong - it's the Porter Ranch leak which the pipe that was capped developed a fracture so the gas is leaking up alongside the pipe. I assumed that there was a plan when the gas was stored to attach something to the cap to allow them to retrieve the gas.

As a result, I have been curious if they are just staying away to prevent igniting it as opposed to attaching a pipe to a pump station to another gas storage location. For all I know this isn't a risk assessment as much as a monetary consideration that the value of gas vented is less expensive than a temporary pumping station and pipeline to put it into another well, and that all the gas is more expensive than cross drilling, so they will leave a giant hazard running to save the difference in cost. The other consideration is that even with the bulk of the flow diverted to a pumping station, there would still be some amount of leakage, which would not stop until the facility was completely drained; while cross-drilling will eventually, supposedly, seal the whole thing.

One detail that I like is that the butterfly valve that would have been used to seal the pipe was removed some years back because the storage site owners couldn't get spare parts (I read that as - didn't want to pay for spare parts) and have done this with dozens to hundreds of other pipes into storage, so there many more wells primed for uncontrolled venting.

It is the IR camera footage that is most enlightening. I really should work the numbers on what the exit temperature is, but am just that lazy. The footage has that gas jet going a short way up and then dropping back on the hillside and down into the community like water and I wonder if that's due to cooling from expansion.

RE: Leaking natural gas storage

Ok. I had to go look that up as I'm not in socal so hasn't come across it.

A usual details are a little scarce, but it seems that the main casing has a leak, with the casing either connected to the reservoir or the inner tubing is leaking into the casing. It seems the casing wasn't cemented the whole way up so there is a leak path out to the surface. The units are odd but they seem to have used mass in all the reports, maybe they think it sounds better that x hundred million standard cubic feet per day. Normally the casing or annulus is at a low pressure and acts like a secondary containment, but maybe here it was pressurised.

The well is but one in a whole field being used to store gas, hence they can't just flow the gas to somewhere else a the volume is massive compared to the single well.

I'm surprised the subsurface valve was that far down the well. Normally it is much closer to the surface as it's primary role is to shut off the well if the wellhead is damaged, not so much if the tubing fails.

This website has the best report I can find www.laweekly.com/news/what-went-wrong-at-porter-ra...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

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