Pipelines 1

[David Norman]

Hello. The Trans Mountain pipeline is approx 1,150 km long. If the ends of the pipeline were simply left open then 'Atmospheric pressure differential' would allow air to flow from the high pressure end to the low pressure end. Today 7 June 2021 10-40 am PT the atmospheric pressure in Edmonton is 1004hPa and 1014hPa in Burnaby, a differential of 10hPa. What would be the air flow through the pipeline if the inside diameter was 24 inches? Can this flow be used to generate electricity? Can a provincial or national grid of pipelines be built to use atmospheric pressure differential to produce a clean, constant power source?
Thanks. Dave.

 

[SuperSalad]

I don't know how feasible that is on the issue of pipework. It would require 1,150 km of airtight pipe. I would think that could be a deal breaker right off the bat.

Edit: I didn't even consider friction losses inside the pipe. Over 1,150 km, That's probably pretty significant for a 0.14 PSI difference.

Andrew H.

http://www.MotoTribology.com

 

[rb1957]

I don't think the idea is realistic.

I think the losses of flow inside the pipe would exceed the "tiny" pressure differential. If the flow did happen, I think it'd take days for the air to traverse the pipe, in which time the local weather would've changed, affecting whatever flow might've started.

I don't know the elevation of either Edmonton or Burnaby, nor along the route of the pipeline ... this would also have an effect.

another day in paradise, or is paradise one day closer ?

 

[1503-44]

I have not looked at the distance between those towns, nor the elevations, or temperature differences, but at 10 hPa, you're not really talking about much more than moving a relatively large fart, no matter what the diameter, for a very limited distance.

Natural gas transmission line 1000 km long would probably have 3-5 compressor stations with losses inbetween of around 40-50 bars. Part of moving gas efficiently is maintaining an average pressure of 30 bars or higher. The higher, the better. Most operate well above that with compressor station discharge topping out at 80 to 100 bars.

 

[Compositepro]

Pipelines are not necessary. We already have wind turbines that extract energy from this same atmospheric pressure differential.

 

[1503-44]

A pipeline I worked on a few years ago in Kazakhstan.
950 km long 30" (720mm) Diameter, 4 compressor stations 10-7-5-2.5 Million M3/day when in low pressure (40Barg) mode.

 

Do you have any idea how expensive pipelines are?

I should know; Justin T paid $4.6B for a used Kinder Morgan line with my money. I was not consulted on that bit of impulse shopping.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[1503-44]

Whom are you asking?

I figure a new one of decent diameter, built in Midwest USA, might run around $2MM/mile.

 

[SuperSalad]

Wait just a cotton pickin minute!

This entire premise is based off atmospheric pressure differential between two areas. But the differential is caused by elevation difference. This theoretical pipeline is not going to negate gravity, so the pressure would reduce relative the to elevation change of the pipeline and the differential would be zero.

Andrew H.

http://www.MotoTribology.com

 

[1503-44]

How do you know it is based on elevation difference? You know the area?
Anyway, doesn't matter for gas, as you say, elevation basically cancels. Plus, since the specific density of gas is 60% of air, the gas in the pipe is likely to rise very, very slowly, rather than actually descend.

 

Maybe we could send ice cubes back the other way, to replenish disappearing glaciers

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[rb1957]

elevation difference is one factor (for difference in local atmospheric pressure). Local weather is as big a factor, and much more changeable.

another day in paradise, or is paradise one day closer ?

 

[1503-44]

Eat my dust!