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Maximum bcf in Natural Gas Pipeline 1

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bonzoboy

Chemical
Oct 24, 2005
89
Can anybody give me an idea of the largest practical flow achievable through a natural gas pipeline? I'm trying to find out what the experience list is of pipelines moving natural gas. For example, is 42 inch diameter, moving 2 bcf per day at 1,000 psig a good benchmark for a single pipeline? For even greater flow requirements, do they just put two pipelines down in parallel? What's the practical upper limit on diameter?

Bonzoboy
 
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The answer is, it is dependent on the size of the pipeline and the pressure it can operate at per se. There are other factors involved (HP, SG of gas, etc.) but that's basically it - from a theoretical standpoint.

I've looked at 52" x 1.000" WT X-80 in a feasibility study. The Russians use 56" (granted without allot of long term success, success being defined at operating at desgin pressure for a reasonable perid of time without leaks).

Constructabilty also plays into it as well as resources available. The 52" I looked at worked fine on paper, but there were not enough contractors or equipment to build it within the schedule needed. There were man other practivcailities that maed it improbable. So what do you do? Well, you can lay dual 36" or other.

It all depends on each situation on a case by case basis, what are the drivers, economics, regualtory environment, gas sales agreements, schedule, mill availability, etc etc etc.

No easy answer.


Greg Lamberson
Consultant - Upstream Energy
Website:
 
"If you build it... they will come." That is THE question.

The practical limit of that size of a system is also very much tied to the ability of the marketing area to consume it. Disposing of 1 BCFD takes a rather large in-place infrastructure and a large organization just to keep up with the supply and demand, never mind running the physical aspects of the system.

I think the record on one rather big system was around 3 BCFD going to the NE US. They had 3 - 30 to 36" diams. It was a very cold week in NYC.

Keep in mind there may be other factors to consider. Political for one. The reliability (and political flexibility) of 3 -36" lines would be much better than 1-56", as the Russians have found out over the years. Even better if all of them do not go through the same countries along their routes!

BigInch[worm]-born in the trenches.
 
There is a 36" gathering system with a maximum flow of 1.6BCF, the farthest point will have 1400 psi inlet.
 
The 52" I referred to had a throughput of 4.3 bcf with a possibility of 5.3 bcf with an optimized HP scheme. The system had a 2,400 psi MAOP. Of course it was just on paper.

Greg Lamberson
Consultant - Upstream Energy
Website:
 
The line gathering line is 50+ miles long and goes up hill.
 
The elevation rise in a 1.0 mile section had an 80 psi drop. Also, most cross country lines have compressor station every 60 to 120 miles. To top it off, two phase flow, gas gathering.
 
decastro, BTW that's a mighty impressive flow in a gathering system. I take it that was a trunk line from several fields, rather than one field alone. I once had almost a 1 BCFD flow from the lower Wilcox, but that was totaled up from 878 wells within 2 fields over a 100 mile radius. I thought that was the record for 1 independent producer... back then... (1987).

BigInch[worm]-born in the trenches.
 
Back to the original question (BTW there is nearly 6 BCF/d leaving the San Juan Basin of Northern New Mexico and Southern Colorado, on its way to California).

It is a completly economic question. If you can tollerate 100 psi/mile then you can move a LOT of gas in a 42-inch pipe at 1,000 psi. It all depends on how much you are willing to spend on compression vs. how much you are willing to spend on pipe.

The rule of thumb that I use is for pipe smaller than 12-inch my design conditions are 15 psi/mile. By the time I get to 30-inch I want to stay below 3 psi/mile. Carrying that out to 42 inch I'd say that a good number is 2 psi/mile so my answer would be 1.13 BCF/day, 4 psi/mile would be 1.60 BCF/day, and 15 psi/mile is 3.08 BCF/day.

If you need to maintain greater than 900 psig, then at 2 psi/mile you would need a $20 million compressor station every 50 miles. At 15 psi/mile you need a $60 million (nearly three times the volume) compressor station every 6 miles.

I have never heard of a 1,000 psig nominal multi-phase line. Typically the spec on big lines at big pressure is under 7 lbm/MMCF of water vapor and no free liquids.

David
 
BigInch

That was the study for the Alaska Gas Pipeline Producers Team, both the "over the top" and the TAPS routes, done in 2000. I was on the ExxonMobil side, succonded to the project as Construction Advisor, Fluor did the study.

On paper everything worked fine, except the economics! At that time it would have taken $5 gas just to break even. That being said there was, for example, not enough 594's or 589's in the world to perform it under the required schedule (2 seasons). One suggestion was, we'll make a deal with Caterpillar to build them.......yeah, okay, but you gotta have someone qualified in the seat and each joint is in essence a large vessel, raised serious construciton safety concerns. That was just one minor example of a multitude of issues we tried to ferret out.

Bottom line, it was not feasible at that time for a variety of reasons. Technically it was well within the real of possibility.

Greg Lamberson
Consultant - Upstream Energy
Website:
 
Greg, Thanks 4 that. I thought that compass was pointing north, which high-lights my original opinion that technology is not the limiting factor in a line of these sizes and you just don't go out and decide to build an X BCF pipeline. With $$$, technology generally can find a way to keep up. Without $$$, nobody builds the stadium. That gas is still a bit "away from the market". At least with North America being the case, there isn't much of any geopolitical concerns to consider; all possible routes having the same risk factor, being there were only 2 countries (at last count).



BigInch[worm]-born in the trenches.
 
Right, and in our case we were planning on bringing it all the way to the Chicago hub.

We also looked at a GTL scheme and tankering it, but again, the economics just weren't there. I felt at the time, as was the common thinking, that the only way it would or will go was if it was stamped a national security priority.

I worked on the X project for ExxonMobil, it was developing X140 pipe, materials, and construction methods to insall it. Interesting stuff.

As we are starting to see in the industry more and more, we have the technology to do allot of things, but we are restircted in many cases by the lack of the personnel to execute the plan. Regardless, you can never get any actual work accomplished sitting in front of a computer, at some point you have to go physically do it.

I think we will very soon see a major capital project that has full funding getting cancelled because there are not enough resources to build it. I know already there are some being pushed back.

Apologies to bonzoboy and the others for getting off track.



Greg Lamberson
Consultant - Upstream Energy
Website:
 
I was not able to keep any files or records as it was confidential at the time. However, I didn't sign a confidentiality agreement, so don't see any issues with some disclosures.

If I recall, Stupp and Nippon provided pipe. I know CRC provided both bending and automatic welding expertise. I left that exercise just before they laid about 3,000-4,000 feet of it and were going to be operating and monitoring it over the coming years, that was back in the 2000 time frame, have not heard of any results. It was kept very low keyed at the time and while I stayed on with them as a consultant until around mid 2003, it was not referenced in any reports or internal updates that I ever saw.

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