Help understanding pressure involving water in two different cylinders

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Branson Sutter
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Please excuse my ignorance. I work for a Natural gas company and have an issue that needs addressed. When gas comes out of the ground it goes into a piece of equipment that separates the water from the gas. The gas goes into a pipeline and the water is dumped into a tank. We are currently trying to figure out which application would have less resistance. So the question is would it require more pressure to inject the water into the bottom of a 12ft wide tank with 12ft of water in it, or to run a 3inch pipe up the side of the 20ft tank and dump the water in at the top. One person claims that the hydrostatic pressure will be higher in the 20ft 3inch section of pipe when full of water vs the 12ft wide tank with 10 ft of water. I don't know enough about this but I figure there are multiple measures of pressure/resistance involved so figured I would ask someone smarter than myself. Thanks
 
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Branson Sutter said:
One person claims that the hydrostatic pressure will be higher in the 20 ft 3 inch section of pipe when full of water vs the 12 ft wide tank with 10 ft of water.
That person is correct. Only the depth and density of a fluid determines its hydrostatic pressure.
The area of fluid container has no effect, the hydrostatic pressure at a given difference in elevation is the same for a giant lake as it is for 0.10 inch diameter tube.
 
JBA said:
That person is correct. Only the depth and density of a fluid determines its hydrostatic pressure.
The area of fluid container has no effect, the hydrostatic pressure at a given difference in elevation is the same for a giant lake as it is for 0.10 inch diameter tube.

Thank you! the water is being moved to the tank by the pressure from the well. Would running smaller pipe, lowering the volume of water, require less pressure to displace any given amount of water into the tank?
 
Branson Sutter said:
Thank you! the water is being moved to the tank by the pressure from the well. Would running smaller pipe, lowering the volume of water, require less pressure to displace any given amount of water into the tank?

I think maybe a better way of asking would be. Is there more resistance, from friction or any other source, to push 10 gallons of water through a 3 inch line full of water vs a 1 inch line full of water the same length
 
No, it is exactly the reverse, the larger 3" pipe will have less flowing friction back pressure and a higher flow rate for a given pipe inlet pressure than the 1" pipe.

For any given flow rate (gpm etc) through a pipe, as the velocity of the fluid flowing through the pipe increases, the pipe's flowing backpressure increases; so, the pipe with the largest inside area will have the lowest flow velocity and therefore the lowest flowing backpressure.