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Explosion at liquefied natural gas plant in Freeport Texas
7

Explosion at liquefied natural gas plant in Freeport Texas

RE: Explosion at liquefied natural gas plant in Freeport Texas

Finally some good news. This might help cool off domestic energy prices a bit.

RE: Explosion at liquefied natural gas plant in Freeport Texas

A/C season is beginning in US. I doesn't look like anybody is planning on using less A/C in the expected hotter weather. 3 weeks down time isn't going to affect this market with anything but up pressure everywhere.

That chart is a slowdown in the rise before a top breaking up. No signal of decreasing price anywhere in that. Drops after middle peaks are decreasing. Plenty of upward pressure to spare. You need three peaks at the same price level to have any significant drop. All arrows are up.

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

I live within a half hour drive of that terminal.

FacEngrPE - I didn't watch the video but I'm under the impression that when the Freeport LNG terminal was first begun (5-10 yrs ago?) it was going to be a natural gas IMPORT terminal. But as the picture shifted and US sources of fossil fuels/gas became more plentiful, the function was changed to export.

=====================================
(2B)+(2B)' ?

RE: Explosion at liquefied natural gas plant in Freeport Texas

https://www.eenews.net/articles/lng-plant-had-hist....

"Freeport released a statement yesterday explaining that the explosion resulted from “the overpressure and rupture” of part of an LNG transfer line. That released a gas vapor cloud, which ignited. The fireball touched off a fire that burned other equipment in the plant. The company release said the LNG vapor cloud was contained within the fence line of the plant and lasted only 10 seconds, while the secondary fire burned for 40 minutes."

"The description of last week’s accident, attributed in part to “overpressure,” offers similarities to an earlier incident at the site. In August 2019, Freeport personnel were opening the first production line, or “train.” PHMSA officials say a pipe failed because the supercooled liquid was being forced, at 917 pounds per square inch, through a pipe designed to handle no more than 90 pounds per square inch.

Further investigation revealed the pipe was flawed and possibly not fit to handle the cryogenic temperatures of LNG. In an enforcement report, agency officials said there were hundreds of feet of such pipe in the facility."


There was an "overpressure" event in a flawed piping system ? ..... I do not like the sound to that

Piping that was "possibly not fit to handle the cryogenic temperatures of LNG" ...... WTF does that mean !!!!!????

Is this carbon steel piping segment installed by mistake in a cryogenic system ????

I do not like this MBA-Speak, lawyer mumbo jumbo ......

What do you think ???

This is 20% of the US LNG stock going through FREEPORT ....

MJCronin
Sr. Process Engineer

RE: Explosion at liquefied natural gas plant in Freeport Texas

Yes I believe it was initially supposed to be for import of LNG. Meaning a few cold lines and lots of warm lines. I can imagine that when they turned the process around, a lot of warm design temperature pipe turned into cold design temperature pipe and v/v, but nobody wanted to think about either low temperature pipe, nor pipe stress reversals.

In any case, it is relatively good news for US domestic consumers, as domestic gas prices have been rising directly with export capacity coming onstream. Domestic price pressure is down, but may still be held up by the dynamic world market to some extent (80%).

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

Interesting ...

"The Freeport facility can produce about 2 Bcf/d of LNG from three trains. It’s also the only liquefaction facility in the United States, and one of only two export terminals in the world, that use electric motors instead of natural gas turbines to drive liquefaction compressors, according to the Energy Information Administration."


https://www.naturalgasintel.com/explosion-reported...

MJCronin
Sr. Process Engineer

RE: Explosion at liquefied natural gas plant in Freeport Texas

> one of only two export terminals in the world, that use electric motors instead of natural gas turbines to drive liquefaction compressors,

Yeah, weird choice. If I remember correctly they had to run some new lines in to support their electric load. And it's not like they don't have the gas available to run the turbines.

> The Freeport facility can produce about 2 Bcf/d of LNG from three trains.

It we interpret it literally, 2 billion cubic feet of LIQUIFIED natural gas per day would correspond to 1.2 trillion cubic feet/day in gaseous state! (assuming 600:1 volume ratio)
I don't know for sure, but I'm guessing they were trying to find a brief way to say that they convert 2 billion cubic feet of natural gas into liquid per day.

=====================================
(2B)+(2B)' ?

RE: Explosion at liquefied natural gas plant in Freeport Texas

It's 2B SCF, Standard Cubic Feet.
US maximum total gas production is around 100-110 BSCF/Day.

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

so you are referring to (standard condition) cubic feet of gas. again a simplistic literal reading would be cubic feet of liquid. the terminology just seemed a little clumsy to me.

=====================================
(2B)+(2B)' ?

RE: Explosion at liquefied natural gas plant in Freeport Texas

Yeah. I guess you just have to know the convention is to always talk SCF of gas. I'm sure the author never gave a single thought that someone might think it was something else. Just goes to show the importance of always carrying units with the numbers. All numbers.

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

...and the units that go with the numbers in your handle are?

RE: Explosion at liquefied natural gas plant in Freeport Texas

-44, that's 2.75 inch tube. Kind of an odd diameter if you ask me.

RE: Explosion at liquefied natural gas plant in Freeport Texas

Time

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

(OP)
Following the PHMSA string MJCronin uncovered,
Federal Enforcement Data FREEPORT LNG DEVELOPMENT, L.P. (Operator ID:32206 - CURRENTLY ACTIVE OPID)

The only enforcement activity open at the time of the current incident was the consent letter from the 2019 pipeline rupture. Link.
From the consent letter the 2019 incident resulted in a requirement to inventory all components manufactured from a specific heat, and then create a return to work plan, which was to include some long term monitoring provisions (which might be the reason this action is still open). The RWP is not posted in the public record.

RE: Explosion at liquefied natural gas plant in Freeport Texas



Numbers it seems can also have directional properties.

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

So ..... I am confused ..

Is there any ongoing investigation of this very serious accident by a regulatory/government third party ?

Or is this just a huge ..... "no big deal, Lets skip it".... moment ?

MJCronin
Sr. Process Engineer

RE: Explosion at liquefied natural gas plant in Freeport Texas

(OP)
I am guessing here but I think based on the enforcement actions on the website, the plant is under the remit of PHMSA, so there will likely be an investigation, but PHMSA stuff tends to have a slower publishing schedule than the NTSB.
The Freeport LNG website newsroom has a posting dated June 14.

Quote (http://freeportlng.newsrouter.com/news_release.asp...)

The incident occurred in pipe racks that support the transfer of LNG from the facility’s LNG storage tank area to the terminal’s dock facilities located on the intracoastal (i.e., north) side of Freeport LNG’s dock basin. None of the liquefaction trains, LNG storage tanks, dock facilities, or LNG process areas were impacted. In coordination with local, state and federal officials, Freeport LNG’s investigation into the cause of the incident, and what steps are necessary to safely resume liquefaction operations, is underway. Preliminary observations suggest that the incident resulted from the overpressure and rupture of a segment of an LNG transfer line, leading to the rapid flashing of LNG and the release and ignition of the natural gas vapor cloud. Additional investigation is underway to determine the underlying precipitating events that enabled the overpressure conditions in the LNG piping.

RE: Explosion at liquefied natural gas plant in Freeport Texas

From LinkedIn; ....... Mr. Geoff Cruickshank
Energy and critical infrastructure security specialist
Edited • 1 week ago

The "explosion" at an LNG plant in Texas might be misreported.
Looking at the footage it appears more likely that the LNG leak was caused by a dropped object, possibly a result of a equipment failure whilst lifting over live plant. The Emergency Response Team are using water spray to direct the vapor cloud away from other parts of the plant, as well as controlling vaporization and boundary cooling. It also highlights the importance of field operators discussing the product in the pipe with the work group when signing on work permits.

The excellent safety record of LNG production means that footage like this is very rare, and will be examined by LNG operations teams to gain insights on how to react in the unlikely event of similar incidents on their facilities. The power of the LinkedIn professional network meant that this footage was discussed in pre-start meeting safety discussions in facilities on the other side of the planet less than 2 hours after the initial event occurred.

Thanks to Mehdy Touil for sharing.

Edit: Appears that in fact there was an explosion and significant fireball that blew itself out. Good footage from nearby CCTV.

https://www.commondreams.org/news/2022/06/09/terri...

MJCronin
Sr. Process Engineer

RE: Explosion at liquefied natural gas plant in Freeport Texas

I don't think that view in the video really gives a proper perspective for how big those three tanks and 10 fans are (and accordingly how big the cloud from the blast was). The placement of the pond and the houses in the foreground give the false impression these tanks and fans are much smaller than they actually are.

You can see those tanks and fans from the bridge between Freeport and Surfside, looking towards Quintana. I'm not sure how to describe them, except... huuuuge.

=====================================
(2B)+(2B)' ?

RE: Explosion at liquefied natural gas plant in Freeport Texas

Caught a 6ft long alligator gar in the channel on the left after the bridge. At 4am, after finally seeing its head under the lantern 2ft away, first thought was alligator!

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

(OP)
This image has something that looks like a missing section of pipe and elbow.

from https://youtu.be/4--mTJJIFmY?t=19

Google map images of the two Freeport TX locations, Huge may be an understatment.

Liqufication and export facility

Pretreatment facility and noble gas extraction facility.

The attachment is a copy of the Federal Energy Regulatory Commission FREEPORT LNG NOBLE GAS PROJECT Environmental Assessment December 2020, it might put one of the site activities into perspective.

RE: Explosion at liquefied natural gas plant in Freeport Texas

1503-44 a 6' alligator gar sounds scary enough, especially in the dark. Myself, I've spent some time kayaking a little bit up the coast - Christmas Bay and San Luis Pass area, but I always try to stay far away from the industrial areas. I'm just a little bit intimidated when I try to imagine what it would be like to be on the channel in a kayak when a big barge or tanker comes by.

FacEngrPE - I think this picture gives a good perspective. Look at the trucks in lower left for scale


=====================================
(2B)+(2B)' ?

RE: Explosion at liquefied natural gas plant in Freeport Texas

268 ft diam measured in Google Earth.
100ft high estimated from number of stairway flights to top.
6MM(Actual)CF (150,000 m3)?

At a gas to liquid conversion of 600:1, its 3T scf/tank.
At US Production of 100BCFD, its 30 days/tank.
Typical LNG ship capacity is 125,000 to 260,000 m3, so tank sizes are right about in the middle of that range.

I did some work at the SPR Bryan Mound site back on the Brazos and I used to fish the San Luis too, back when it was a KOA camper land, but preferred the mouth of the Brazos and Colorado rivers and Lavaca Bay. Wade fishing the Colorado on the sand bar about a half mile out, before they built the jetty, with a load of trout on a my stringer, a large blackfin passed me by at about 20ft. Time to get out the hell out of the water. It was known to be frequented by some very large sharks. That scared me more than both the alligator and the time I got hit by a wake and washed off the Galveston jetty ... about 2 miles out. Used to watch the guys bring their girlfriends to KOA on Friday night, then turn up on Saturday night fishing with the wife and kids. Ah yes. Life before Internet and mobile phones.

RE: Explosion at liquefied natural gas plant in Freeport Texas

Is this Freeport Company related to the giant Freeport McMoran copper/gold mine Company in West Papua - Indonesia ?

https://youtu.be/jwxJwul0TQs

RE: Explosion at liquefied natural gas plant in Freeport Texas

Interesting, that link has a good timeline of how Freeport LNG switched from an import terminal to an export terminal. I guess the infrastructure providing access to ships and pipelines at that location was unchanged. But the conversion equipment changed significantly. They had to add compressors and fan coolers. Working at an electric generating plant in Texas (using a fuel that is not gas), we considered that a positive development in our business environment because not only did it tend to increase the price of gas used by competing generators, but it also added electrical load of up to 690MW.

Quote:

Freeport LNG requires 690 megawatts (MW) of electric power supply to operate three liquefaction trains, almost 9 times the Freeport area’s previous load, which was less than 80 MW. Several electric transmission upgrades (including Jones Creek transmission project) were implemented on the Electric Reliability Council of Texas electric power grid to connect transmission lines with Freeport LNG to accommodate the additional load requirements.

Again, strange choice to use electric motor driven compressors instead of gas driven, although I'm not sure what share of the load that is.


=====================================
(2B)+(2B)' ?

RE: Explosion at liquefied natural gas plant in Freeport Texas

The electric drive choice was probably made to avoid exhaust emissions at the site, which conveniently transfers that burden to whomever is doing the electric generation, but since they're also selling 690MW, I'm sure that's included in that cost. Everyone's happy ... even the nukes.

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

And now there's speculation that this was the result of a hack by Russian operatives:

Did Russian hackers blow up a Texas LNG pipeline on June 8?

https://www.washingtonexaminer.com/opinion/did-rus...

This issue is being raised because Russia sees the US exporting of LNG to Europe as being a direct threat to their control over the energy supplied to Europe.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Explosion at liquefied natural gas plant in Freeport Texas

Russia is creating their own threat to their control of EU energy. Before Russia's invasion they had direct control over EU energy and the EU was happy about having a secure, nearby energy source. I would not say that now, in fact the exact opposite, Freeport LNG (USA) has more control over EU future energy supply than Russia does. Russia might as well be pumping mustard gas. Nordstream II is dead and Nordstream I is on life support. If Russia ever wanted control over EU energy stocks, then Ukraine invasion is the biggest blunder since Coka Cola New.

I've said before that Russia didn't want any control of EU energy source, they just wanted to sell gas. What they wanted was for the USA to stop messing with Georgia and Ukraine and for the USA to drop their sanction and threats concerning Nordstream II, because that interfered with their gas sales business. With sanctions getting worse by the minute on Nordstream II, and US advisors all over the Ukraine, what did Russia have to lose, except the Ukraine itself, which they saw as even worse result than losing their already essentially lost gas sales. I don't think the war is justified, but neither can I say that its entirely on Putin. Push a psychopath too far and sh*t happens. What we are seeing is the oil companies winning again, even though everyone else is losing. Hummm.... I'm getting that ole deja vu feeling. Oil company profits up, USA sells more gas. Europe pays. USA proves that Russia was indeed a sheep in wolf's clothes. When all the pieces fit so nicely together, I suspect that the puzzle has been gamed many times over. My butt itches.

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

jrb - your link didn't work but this one works for me: https://www.washingtonexaminer.com/opinion/did-rus...

I can see where suspicion falls in that direction regardless of the actual cause, so I’m going to keep an open mind waiting for investigation results.

No doubt Russia’s effort backfired in terms of effect on both Europe’s security posture and Europe’s energy posture. If Russia envisioned they would be needing to leverage Europe’s energy dependence to coerce them, they probably would have been better served to attack in the Fall (due to much higher demand in winter).


In terms of not foreseeing correctly, one wonders if we (the US) could go back in time to early February when our intelligence knew what was coming, knowing what we know now about the effects and duration of the war to-date, would we have been better served to bring more to the negotiating table? While I’m reluctant to suggest anything that rewards aggressive behavior, I lean towards saying yes.

=====================================
(2B)+(2B)' ?

RE: Explosion at liquefied natural gas plant in Freeport Texas

Sorry, I had the wrong link (I've corrected it).

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Explosion at liquefied natural gas plant in Freeport Texas

I don't think anything backfired, except the 3 day blitzkraig war plan. That didn't work.
Otherwise, it's not reasonable to assume that nobody at the Kremlin can connect the dots to reach this point. Russia didn't think that sanctions would happen? No, they were expecting them. They had already made a deal with China to take as much oil as possible (my conjecture, but surely included in the "Friends Forever Deal"). Nordstream sanctions were already imminent, except for Germany's strong objection and last minute deal with the US to stop them at the NATO conference in late winter. Russia already knew that there were ways to deal with sanctions. Today they make more selling less oil and everyone in the west is paying for that, proving again that sanctions simply do not work. Cuba still exists. Iran is building nukes. NKorea is nearly launching them. (Except they do work for big oil.) Even Ted Cruz (or his big oil bosses) had connected those dots a long time ago. Everything is right exactly on track, albeit with a few delays in taking Kiev.

I think the above scenario works, exactly because it does not rely on underestimating the opponents ability to connect any dots at any point. No mistakes, just delays in the schedule execution.

What negotiations? Nobody was or still today seriously talking to their opposing sides. What've we got to bring to what table? We'll start buying your gas again, but at the old price? The only real backfire I see is ... the sanctions. Oops. As Pogo used to say, "We have met the enemy and he is us"



A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

Obviously the choice to go electric was to improve the appearance of the plant on paper. These types of actions are why I can't get behind the green movement. It isn't real. With a gas turbine plants they could have used cogeneration to reduce their real CO2 footprint. The obvious course would be heat recovery steam generators to make electricity but I wonder if absorption cycle refrigeration would be of benefit for liquifying the gas?

RE: Explosion at liquefied natural gas plant in Freeport Texas

Chances are a similar system, or nuclear, is being used to generate their purchased power, so it does not really matter where it is generated, as long as it isn't by oil or coal fired, or otherwise dirty sources, plus supposedly there are advantages in the economy of scale combining loads into large centralised power plants. Its probably a good base load. Costs are lower, efficiencies are better and concentrated emissions are easier to clean up and capture if such be the case. Actually better to do that in the end, if you can. The key is more the availability of a reliable grid power source. When a reliable source of 690MW is not available (Texas Grid ???), fine, generate your own power on site. Otherwise its usually cheaper to buy off the shelf.

Most large scale liquification plants are using Air Products proprietary technology.
https://www.airproducts.com/company/news-center/20...

https://www.qatargas.com/english/operations/lng-tr...

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

JohnRBaker; From LinkedIn: ... an update

Reports that a Russian cyber attack might have been behind the explosion and fire at the Freeport LNG explosion are unfounded, the company recently said.

“While our ongoing investigation continues, a cyberattack was ruled out as the cause within days of the incident,” Browne said in a statement Thursday afternoon. “After a thorough assessment of our network, our internal cyber detection systems have been confirmed to have been functioning properly and do not indicate any manipulation or compromise of our security solutions.”

Freeport LNG released information last week that the LNG piping became overpressured and believes the issue occurred in the pipe racks supporting the transfer of LNG from the storage tank area to the terminal’s dock facilities on the Intracoastal Waterway or north side of Freeport LNG’s dock basin.

https://thefacts.com/news/article_c9da6301-a0e9-52...

..... So now it looks like it's the Pipe Racks !!!! .... It's always those damn troublesome pipe racks !!

Naaaaaaaaaaaaaaaaaaaaaaaaaaaa..............

I still put my money on a piece of renegade carbon steel pipe that was welded into a cryo system by two TEXAS pipefitters named Jethro and Billy Bob .... They ran out of the 304 stainless pipe that was required for the job ..... so they used an old "pup piece" that they found out in the "back boneyard"

Jethro was heard to say: "Uh pipe iz uh pipe !, Ah reconn .... Ain't no sense in a-payinn my mind to no fancy "Pee-an-Eye-Dees" !!!!

MJCronin
Sr. Process Engineer

RE: Explosion at liquefied natural gas plant in Freeport Texas

Nope. I'm betting on a minimum of 10,000 ft of it.

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

Quote (The Facts newspaper)

An update to the article Thursday afternoon, after Freeport LNG’s statement, added the Quintana site does not have the Operation Technology/Industrial Control Systems network detection systems necessary to detect XENOTIME’s ICS-targeting TRITON malware and a cyberattack cannot be ruled out.
I think it's just going to be awhile for a confident diagnosis of the cause to emerge one way or another.

But yeah... Jethro and Billy Bob are probably at the top of the list!

I actually work with someone who calls himself "Jim Bob" (having grown up in the northeast, it's hard for me to get used to saying that name with a straight face, but it doesn't faze the locals one bit).

Quote (electricpete)

You can see those tanks and fans from the bridge between Freeport and Surfside, looking towards Quintana. I'm not sure how to describe them, except... huuuuge.
As it turns out, I went over that bridge on a beautiful sunny day last Friday on the way up the coast to Galveston. My wife was driving (as she's wont to do... she thinks she's the better driver within our marriage... my vote is D.K. effect for self-evaluation of driving abilities applies to her but certainly not to me). So I grabbed a snapshot from the passenger side window looking over the cement siderail of the bridge (attached).




=====================================
(2B)+(2B)' ?

RE: Explosion at liquefied natural gas plant in Freeport Texas

Better to let her drive while you and Billy Bob are passing cold ones around.
I guess the flag blows the other way when the fans are running.
That used to be a Coast Guard station there in the center of the picture.

I was crossing that bridge one time when a speeding car came over the top and a minute later, three police cars followed chasing it. Just like a Burt Reynolds movie.
And designed a 180ft stair tower and an elevated reactor building foundations and enclosure structure at the Badische plant a few miles behind you.

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

Important releveant discussion: https://www.eenews.net/articles/lng-explosion-shin...

“It’s important to remember that LNG poses unique safety risks, often above and beyond those posed by other hydrocarbon transportation, due to the high pressure and density,” said Bill Caram, executive director of the Pipeline Safety Trust, a Bellingham, Wash.-based safety advocacy group that tracks LNG safety.

Seven LNG plants are currently operating, handling billions of cubic feet of methane every day and making the United States the leading exporter of natural gas. More than a dozen new plants or production lines are planned or under construction. The United States exported nearly 10 billion cubic feet of LNG per day last year, up from essentially nothing in 2015.

The industry has indicated that it is open to new rules from the Pipeline and Hazardous Materials Safety Administration (PHMSA), but is already setting expectations. The Center for Liquefied Natural Gas is calling for flexible, “nimble” regulations and a “holistic” approach that “exchanges expertise and innovation between safety officials and industry.”

MJCronin
Sr. Process Engineer

RE: Explosion at liquefied natural gas plant in Freeport Texas

And the immense quantity of gas that could be released. It seems that they totally depend on dissipation within a rapid amount of time by mother nature. Obviously distance to other facilities is hardly relevant.

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

Apparently they're claiming that the LNG that might leak at an export terminal can pose more hazard than other LNG leaks from the standpoint that it's not necessarily lighter than air due to the low temperature and the chemical composition.

Quote:

The main physical danger at an LNG site is a leak forming a cloud of low-lying natural gas that drifts until it hits an ignition source — even simple static electricity — and bursts into flames. Experts worry that, since so much gas is stored at each terminal, damage could spread from one part of the facility to another and spiral out of control. That’s apparently what happened at an Algerian LNG terminal in 2004. A gas leak touched off an explosion that destroyed three of the plant’s six liquefaction trains and killed 27 people.

...Current assumptions, Havens says, are built around the properties of methane, which is lighter than air and disperses upward in the event of a leak. That might have been adequate for a previous generation of LNG terminals designed for importing methane into the United States. But at export terminals, where gas must be chilled to minus 260 degrees Fahrenheit, the production lines are rife with “heavier hydrocarbons” such as ethane and propane that present a higher risk of exploding.

=====================================
(2B)+(2B)' ?

RE: Explosion at liquefied natural gas plant in Freeport Texas

They seem to place a lot of faith in vapor barriers, tall solid faced fences, to contain gas spreading out. Maybe too much for me.

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

For anything that's heavier than air, those 'vapor barriers' are probably as effective as anything that they could construct around a facility like that.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Explosion at liquefied natural gas plant in Freeport Texas

I'm pretty clueless about the safety aspects of these things and what are the particular scenarios they're trying to protect.

I'm gathering from the discussion that the idea of the vapor barriers is to hold the vapor in at the site rather than allowing it to dissipate outward?

I guess I can see how that is supposed to protect the public outside, but at first thought it seems the opposite of what you want to do (since it makes it a lot more likely to quickly develop explosive concentration inside)

Are there any scenarios where a fire in the plant causes heating of the liquid tanks, lifting relief valves which further feeds the fire/heat? I'm not sure how all that works, but it seems like the worst case scenario would occur if all the stored energy in those liquid tanks can somehow be released.


=====================================
(2B)+(2B)' ?

RE: Explosion at liquefied natural gas plant in Freeport Texas

Compressed gas type stored energy release here depends on the liquid to gas conversion rate, which may be relatively slow. At liquid temperature, pressure is low, so there is relatively small amount of stored energy in a pressure explosion sense. You would not want the gas to form in the tanks. They won't hold gas pressure. Cracked or intentionally penetrated, or destroyed tank, by terrorist activity is probably the worst risk scenario. At least some LNG import/export sites seem to have some kind of enhanced security involving Coast Guard and harbormaster patrols, procedures and exclusion zones, but I'm not sure what or how is actually being done.

Pressure build ups must be released immediately. Relief valves to vents or blowdown locations in a "safe place" is the usual procedure. Maybe venting behind water curtains??? I do not know.

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

(OP)
1503-44 brings a good point. Every place that can have liquid natural gas present must be protected against over pressure, even every segment between any two valves, the vacuum space in vacuum insulation, etc. The pressure that can result from a closed in temperature excursion are really high. Ambient temperature is well above the critical point for LNG.
Loss of vacuum in a vacuum insulation system can cause over pressure if the hydrostatic relief valves are not sized for the increased heat gain.

So start at 700 psig, then add in the gas expansion between -110F and ambient. Perhaps upwards of 1000 psi?

RE: Explosion at liquefied natural gas plant in Freeport Texas

Quote:

268 ft diam measured in Google Earth.
100ft high estimated from number of stairway flights to top.
6MM(Actual)CF
At a gas to liquid conversion of 600:1, its 3T scf/tank.
It occurs to me to try a calculation which is undoubtedly overly alarmist (It’s probably similar to the thought process of people erroneously equating nuclear power plants to nuclear bombs). Nevertheless, if the entire tank somehow bursts and the contents combine with air in a single explosion representing complete combustion of the contents, what would be the level of destruction?

3E9 scf NG/Tank * (1E3 BTU/FT3) * (1KilotonTNT / 4E9BTU) = 750 kilotons TNT per tank (50 times as big as Hiroshima, from one tank, if my math is right... I'm open to correction).

I don’t know how to convert that to a danger radius, but it does raise eyebrows at first glance for anyone living nearby. But without knowing details of probabilities or credibility of these types of events, at least it’s somewhat comforting to note many similar tanks have existed (for a decade or more?) and while there have been a few explosions, they have been on a much smaller scale.

=====================================
(2B)+(2B)' ?

RE: Explosion at liquefied natural gas plant in Freeport Texas

Not going to argue about it being big. That's for sure. Prevention is the key.

An LNG primer.
https://www.spegcs.org/media/files/page/bf3787c6/O...

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

Whoa !!!!!! ......

Half your plant explodes with a giant fireball and here come the feds ?....Couldn't have seen that one coming, Jethro !!!!


REUTERS/WAPO (6/30/22) --- U.S. regulator bars Freeport LNG plant restart over safety concerns !

https://www.reuters.com/business/energy/us-regulat...

https://www.washingtonpost.com/business/economy/us...

________________________________________________________________________________________________________________________________________

Also in Bloomberg:

Shuttered Texas LNG Plant Delays Restart After Federal Order Blast at Freeport LNG terminal has send gas futures plunging
--- Government notice raises questions about length of outage

"Preliminary evidence suggests that an isolated pressure safety valve “created an overpressure situation” in 300 feet of vacuum insulated piping, according to the federal notice. The piping then burst and allowed LNG and methane to be released into the facility, causing a subsequent explosion and fire that damaged piping and components in the plant, the agency said."

https://www.bloomberg.com/news/articles/2022-06-30...

MJCronin
Sr. Process Engineer

RE: Explosion at liquefied natural gas plant in Freeport Texas

I'm glad they are going to be slow and deliberate about it.

Aside from needing to know what was the root cause (to determine whether it suggests more latent problems are hiding), there is probably a need to be able to prove that the safety-critical structures (like those big-ass insulated tanks) were not damaged/weakened by the blast in any way.

The link also states "U.S. natural gas futures tumbled 15% on Thursday due to the report and on a continued inventory build, contributing to a 33% price drop in June, the biggest monthly drop since 2018". That was surprising to me. I guess (?) the US natural gas prices are not well coupled to the European gas prices, and the loss of an export terminal only further decouples those markets.



=====================================
(2B)+(2B)' ?

RE: Explosion at liquefied natural gas plant in Freeport Texas

FacEngr called it. Vacuum insulated line.

The domestic gas price has been rising directly with increasing export capacity. The speculators think this lost export gas will find its way into the domestic market, where it will create an oversupply and reduce the domestic price. Happy days for US consumers.

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

All military world wide are like this now.

Actually The USA sapper corps have more clue than most but I suspect they were kept away from this "issue" because the local Navy corps didn't want to admit there was a problem and they only wanted to make it last until the next posting and then it would be someone else's problem.

RE: Explosion at liquefied natural gas plant in Freeport Texas

Thanks for the link FacEngr.

"AN ISOLATED RELIEF VALVE caused overpressure of the pipe ..."

Disabling a relief valve! The most amature of all possible mistakes, yet one of the most common. Relief valves make too much noise. Better to close them off. I've seen that so many times that I refuse to put block valves in relief lines. The temptation to close them is just too great.

Alistair, that goes in the other thread.

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

(OP)
I have had some experience with welding shop cryogenic tanks. Preventing closed in sections of pipe where possible, and providing relief valves on every isolatable section is critical for safety.
The only part of the system we insulate is the storage tank, the tanks our gas supplier provides are vacuum insulated with large rupture discs on the vacuum space. The tanks are provided with duplicate relief valves on a valve block designed so one of the valves can be closed off for service, but not both at the same time. (the same thing is done with propane tank relief valves).


I realize this approach may be difficult with 18" pipe, but if relief valves in a cryogenic system need to be removed for service with the system charged, the solution needs to maintain this same function (or you need to rely on administrative controls).

RE: Explosion at liquefied natural gas plant in Freeport Texas

DOT is now getting involved in this significant FREEPORT LNG incident and explosion

https://www.phmsa.dot.gov/news/phmsa-notice-propos...

https://www.phmsa.dot.gov/sites/phmsa.dot.gov/file...

"Although the root cause of the failure has yet to be confirmed, preliminary evidence
suggests that an isolated pressure safety valve created an overpressure situation in 300 feet
of vacuum insulated piping. The 300 feet of pipe was subjected to an overpressure situation
which burst the pipe and allowed LNG and methane to be released into the facility. The
sudden release of LNG and methane from the piping caused a subsequent explosion and
fire that damaged piping and components in the plant."

MJCronin
Sr. Process Engineer

RE: Explosion at liquefied natural gas plant in Freeport Texas

The PHMSA notice provides a welcome return of confidence in some gov't depts, after the discouraging 2 yrs of dissappointment that resulted from the CDC/ NIAID handling of the Covid 19 crisis.

One may want to understand if B31.3 allows operation of a piping system with the requisite relief valves isolated. Most codes only pertain to the design and supply of equipment to be provided by the design engineer and do not specifically define operating procedures, but allowing "administrative control" of safety valves at the nation's 2nd largest LNG facility seems a bit over the top.

I had reviewed the initial design arrangement of one other LNG facility, and pointed out that the phase 1 ground level flare system made it impossible to complete construction of phase 2 if phase 1 was in service, as a release of gases to the flare ( from relief valves) would toast the workers assembling the nearby phase 2 flare system, but the criticism was ignored, as schedule/money was of the essence. Perhaps the management thinks that release of gases from a relief valve is a predictable event- one hopes they don't learn the truth the hard way.

"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick

RE: Explosion at liquefied natural gas plant in Freeport Texas

(OP)
Title 49 Part 193 has words that should result in a requirement similar to OSHA Process Safety Management standard. This should have resulted in a rigorous discussion about safety valve isolation administrative controls, and requirements in the plant operating manual.
It will be interesting to see how the investigation develops.

RE: Explosion at liquefied natural gas plant in Freeport Texas

The report refers to vacuum insulated pipe as follows:

Quote:

The 18-inch vacuum insulated pipe consists of an inner and an outer stainless-steel pipe with covering shroud. The inner pipe carries the cryogenic liquid. It is wrapped with multiple layers of super insulation made of alternating layers of a heat barrier and a nonconductive spacer. This creates a space between the two pipes that is “pumped down” using a vacuum pump to create a static vacuum shield. The vacuum shield protects cryogenic liquid from heat loss due to conduction, convection, and radiation.

So an inner insulated pipe which contains the liquid inside, and an outer pipe, and a vacuum space between them which is pumped down by a vacuum pump.

Are there alarms when the vacuum is not sufficient to maintain insulation?

If the relief valve were not isolated, would it be connected to the inner liquid chamber? (rather than the intermediate vacuum chamber)

By the way if I use 18" outer diameter to calculate the volume of a 300' cyclinder, I get pi*300ft*(1.5/2)^2=530 ft^3 or (with 600:1 volume ratio) 318,000 SCF. But the report states 120,000 SCF leaked which is only 38% of that 318,000scf. I realize some of that volume is occupied by the intermediate vacuum chamber, but I don't think it would be 62% of the volume (leaving only 38% for the liquid), would it? Is it reasonable to conclude the pipe was initially only partially filled with liquid?


=====================================
(2B)+(2B)' ?

RE: Explosion at liquefied natural gas plant in Freeport Texas

The pipe contained a mixture of gas and liquid. As the temperature rises the liquid boils, gasifies and raises the pressure, in this case too much.

The relief has to be connected to the inner pipe. Everything is there. Nothing should normally be in the annular space. You would want to limit pressure there, which would also limit the pressure entering the annular space, if it did happen to find a way in there.

I doubt that there is any alarm on loss of vacuum. (maybe) That's what the relief valve is, in a sense.

This is a stupid mistake that caused a lot of damage. Super lucky nobody died.


A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

NG Phase diagram
They probably were somewhere in the mid to lower central mixed phase region.





A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

(OP)
I would expect the vacuum space to have rupture discs. Once you loose vacuum and have an overpressure in the vacuum space, a relief valve that reseats does not help anything, as any repair of leaks involving the inner pipe and other internals involves cutting the vacuum containing outer pipe open.

RE: Explosion at liquefied natural gas plant in Freeport Texas

Meaning a disk, or relief valve connected to the annular space (?).

Burst disks are do messy with inflamables. Never used one.

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

(OP)
Not having practical experience with cryogenic flammables (other then propane) my opinions might not pass 1503-44's evaluation. The idea about using rupture discs on the vacuum space, comes from the fact that it is really hard to get relief valve seats completely leak proof as need to maintain higher levels of vacuumed. Of course even if the plan is for the relief on the vacuum space to never operate, it still needs to be aimed in a direction that would be away from important equipment and occupied spaces. I would be surprised if this relief was taken to a flair stack, due to the hopefully low likelihood of it needing to operate.

One other thought. In this environment how are relief valves protected from getting stuck with ice from condensation? One side being exposed to possibly cryogenic conditions, and the other to hot humid coastal air.

RE: Explosion at liquefied natural gas plant in Freeport Texas

I think that there probably is no vacuum protection, alarm, relief or burst disks attached to the annular space. The best way to keep a vacuum is to weld every joint and not to have any connections to it. Least that's how we do it on encased, insulated, offshore pipelines where the annular space is not a vacuum and contains only an air gap, or insulation, either of which must remain dry. The annular space and casing pipe is sealed between "flange" fittings at each pipe joint. The flange there being a flange, but with a weld neck on each side. That may also be the design strategy applied here, where the vacuum is maintained joint to joint, rather than in a continuous annular space from beginning to end of the pipeline itself. I think there is an LNG import terminal in Peru that might be doing that, brining the LNG in from a body, rather than loading arms along side a dock. I do not know the specifics of LNG pipe design. I have designed an ammonia pipeline (-29C) with insulation and an HDPE jacket pipe that was enclosing a continuous annular space, so there are various ways the cat can be skinned. I just don't know what was done in this plant.

The relief valve in question must have been connected to the LNG pipe. That's the pipe that must have over-pressure protection (according to all pipe design codes I have worked with).

A loss of vacuum would be noted by an unexplained increase in the temperature profile, gasification of the LNG and subsequent pressure rise, then relief valve activation at over-pressure, if it wasn't isolated, just as this system was supposed to work. An independent alarm on vacuum loss might be nice, but doubtfully specifically required by code.

Natural gas pipelines can also freeze during rapid blowdown. The Joule-Thomson effect reduces the gas temperature at the outlet, condensing and freezing the valve. The blowdown rate is limited to avoid freezing. Surely the relief valve for LNG must be pretty heavily insulated.

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

RE: Explosion at liquefied natural gas plant in Freeport Texas

(OP)
I was thinking about the long periods where the relief valve just sits doing nothing. Ensuring that ice can not form inside the relief valve while it is watching an inspec system (hopefully it's entire service life) seems like a tall order.

As stated in most codes, "This Code is not a Design Guide". As we all have found in our practice, we need to go beyond the applicable codes to build safe systems.

PSM should be part of the design process, as an aid in designing out hazards. Administrative controls while often necessary, are not sufficient for safety.

http://websites.umich.edu/~safeche/swiss_cheese.ht...

Quote (http://websites.umich.edu/~safeche/swiss_cheese.ht...)

The main purpose of the Swiss Cheese model is to visualize how a hazard may be able to pass through the vulnerability of the many different measures in place.

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