INGROUND CNG INPUT 1

[hemisboats]

I have,, like so many others, a natural gas well in the North East 5 miles inland from Lake Erie, PA. that slows significantly in the cold weather. Therefore a solution has been contrived (in my head) to pump the gas into tanks during the warm summer when the well produces hundreds of pounds and unlimited (for my needs) volume.

The question, can anyone tell me if they have heard of using propane takes buried in-ground to advantage the 55 degree mean temperature of the earth. My thoughts were to pump them to approximately 2/3 the rated pressure and at the 1800 foot elevation temp. would control the expansion coefficient.

Any thoughts?!

Thanks,
Neal

 

[BigInch]

Underground tanks are a problem for corrosion, inspection, leakage and regulations. You may need to double wall them. Permit them. Inspect regularly. Too expensive. Too much hassle.

At 1800 ft under a shade roof structure, you should be able to keep them relatively cool.

Tank pressure is temperature dependent; nothing to do directly with elevation.

What's the flowrates, gas temperatures (not air or soil temperature) and SG in summer and winter?

Cold gas is more dense, maybe you get nearly the same number of lbs mass as in the summer, even with the lesser flow. Have you tried using a line heater to keep the temp up and the hydrates from forming and blocking the flow.



Only put off until tomorrow what you are willing to die having left undone. - Pablo Picasso

 

[hemisboats]

Not yet. I'm 475' away from the well. It was drilled in 1972, I believe in the Medina vain and was never connected to a pipeline as the responsible co. went bankrupt. The well was completed so the owner at the time would get gas. However, winter came and pressure dropped and the well lay dormant until this fall.

The well was not set up poorly I believe as there was no drip tank before the Big Joe regulator.

 

[MortenA]

I thnik biginch is moving in the right direction: Why is the flow slowing during winter?

I would think the the pressure and temperature in the reservoir would be independant on outside ambient temperature? I mean even a few feets down the soil temperature is independant and ambient temperaure and although i have heard about shallow gas i allways thought it was a bit deper than that.

Therefore it must be someting else.

Cooling of the topside part of the well and flowlines will ofcourse occur, but this should not cause WHSIP to drop - since more gas from the reservoir should just flow to the well.

Therefore i think the Biginch theroy about hydrates sounds plausible. Maybe its hydrates or even ice that blocks valves or pipes and prevent the gas from flowing? Heating the pipes could clairify this.

Best regards

Morten

 

[hemisboats]

MortenA

Thanks for the input. My plan is to move the drip tank to pre-regulator position. Hopefully we get better cold weather results.
Current config. attached. Blue arrows pre-regulator, red is regulators, green into and out of drip tank.
Thanks,
Neal

 

[BigInch]

Probably a better arrangement. Chances are you may free up the requlator. As Morten says, gas temperature from the well shouldn't vary too much at all, so it is likely to be solved by keeping the piping free of freeze plugs and as warm as necessary to prevent them. Knocking out free liquids as soon as possible is a good start. Doubtful you will be able to make any other change, not involving reworking the well, that gives permanent results, except for trying that line heater.

Only put off until tomorrow what you are willing to die having left undone. - Pablo Picasso

 

[BigInch]

Unless you want to try injecting freeze inhibitors.

Only put off until tomorrow what you are willing to die having left undone. - Pablo Picasso

 

[dcasto]

why not remove the pressure regulator and run the gas to the area where it is used and have a electric heat traced regulator and drip.

 

[hemisboats]

Good question! As long as we don't bring the high pressure into a dwelling.

Hmmmm?!

 

[bcs5274]

the gas straight from the well is "wet", i'm thinking the moisture freezes to the pipe in cold temps and chokes off the flow from the well, if you can insulate it or as we do here put them in a building with a catalytic heater then bubble the gas through methanol to eliminate the moisture you should be good all year long

 

[hemisboats]

Good point! What kind of up front and continued cost of the Methanol Bubblier?

 

[bcs5274]

we use a a 20 inch or bigger casing and cap it with a 1 in pipe going to with in an inch or so of the bottom, a one inch collar welded to the top, on the side is an elbow on the side to fill, usually hold ten to 15 gallons of methanol, fill in the fall and works all winter for a house/shop use

 

[BigInch]

Sounds like fun. First, I'd just try keeping it warm, unless you're a certified welder & Chem E.

Only put off until tomorrow what you are willing to die having left undone. - Pablo Picasso