Which is better Horz. or Vertical Pressure Vessel 4

[mo7amedsalem]

Please help me, which one is better? the horz. or vertical pressure vessel which is used for anti water hammer systems? or for any system as general?

 

[mo7amedsalem]

or in another way,, What is the advantages and disadvantages of Vertical pressure vessels and Horz. ones?

 

[austsa]

Large vertical vessels have to cater for larger wind & seismic loads. Access is harder. Static head needs to be considered. Installation is more difficult.
Vertical vessels drain more realiably and faster. Requires less space.
Generally though, vessel orientation is dictated by process.

 

[DRWeig]

I have always had to choose based on capacity, floor space, and head room. In the commercial / institutional building world, the architects provide the constraints.

I agree with austsa's pros and cons on vertical. Given unlimited space, I would always prefer horizontal if that fits into the process scheme.

Good on ya,

Goober Dave

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[TD2K]

Do you have a feel for how big of a vessel you are talking about?

For a pipeline I know we did a lot of surge analysis on, the surge relief system went to a conventional storage tank, several thousand gallons. Is this on the scale of what you are looking at or something a lot smaller?

How do you plan to operate this system?

 

[mo7amedsalem]

In my case, i'm dealing with a 10m (32 feet 945⁄64 inches) height and dia 3m (9 feet 107⁄64 inches) tank and i have no Arch. constrain about the height. it's my own decision to install it vertical or horz. so Is the vertical position better or horz.? given it's a surge relief system (anti water hammer system) in lift pump station.

thx in advance

 

[TD2K]

I'd likely make it a horizontal vessel.

I expect you are going to have some level instrumentation and access to the upper taps will be a lot easier with a horizontal vessel. In addition, instrumentation and operations will usually want an independent sight/gauge glass to verify the level transmitter's reading, that's a lot of additional sight glasses to cover a 10m high vessel because you won't get one that will span 10m.

Foundations costs should be less expensive with a horizontal as mentioned by others. The lower part of the vertical vessel might also have to be thicker to accommodate the additional static head which will add cost because you'll need more steel. That may or may not be a factor since you are talking about 3m static head versus 10m static head between the two orientations.

You haven't mentioned anything about how this vessel is operated but that might also have some factors in selecting a horizontal versus vertical.

Since it's a pressure vessel, it will have to be inspected occasionally. I would think a horizontal vessel is easier to inspect but check with your inspection people.

 

[zdas04]

I did a similar analysis in 1996 on a gas gathering system running at 300 psig and it worked as designed (I did put a full diameter boot under the vessel to improve performance with small slugs).

In 2001 we lowered system pressure to 35 psig and started having problems with very large quantities of water vapor condensing in the compressor station. It turned out that the large liquid/gas interface within the vessel was taking 20% RH gas back up to near 100% and the amount of condensation after the booster compressor was more than the station was designed to handle. The only way we "solved" that was to move the dump switch to the bottom of the boot to keep the vessel as dry as possible. It didn't work perfectly, but we got to where the station was going down on high scrubber levels monthly instead of daily.

At another station we installed a similar capacity vertical vessel that worked well at high pressure (greater than 150 psig), and continued to work well at low pressure (less than 30 psig).

Since that experience I look really hard at the potential for the system to operate at low pressure when I make the vertical vs. horizontal decision. If there is a good chance of future low pressure I go with vertical and deal with the wind loads, foundation issues, etc.

David

 

[TD2K]

Why do you want to make vessel a pressure vessel rather than an atmospheric tank?

 

[EngAddict]

All the large volume low pressure surge vessels we design are vertical but still operate well above atmospheric pressures. I think it is governed by the fluctuation velocity and duration. These vessels have all been high velocity fluctuation with compressor systems to maintain the differential pressure above the water column. For slow, large volume surge systems you could likely use an atmospheric tank.

However this is generally well covered by the water authority specifications and process design. This would not be up to the vessel designer to nominate.

 

[JStephen]

In that size range, I would go with horizontal if it's a pressure vessel, or vertical if it's atmospheric.