6 replies to this topic

[romianne]

Hi. I need some help with this: If there is 70 kg of water in milion Sm3 of natural gas (taken from figure in Campbell's gas processing book, at water dew point -10 C and 5 MPa), how much water is there in 2.5 milion gas m3/d at 5 MPA and 15 C? Consider standard conditions to be 15 C and 100 kPa. Thank you very much.

[MrShorty]

Is there a specific part of this problem that you are stuck on or don't understand?

 

Hopefully it is not doing too much for you. You are given a ratio (70 kg water/1E6 Sm3 gas) and are asked to find a total water. My first thought for something like this is to set it up as a proportionality. (If you need an algebra refresher on how to solve proportions, I recommend http://www.purplemat...ules/ratio2.htm).

 

70 kg water : 1E6 Sm3 gas = x kg water : y Sm3 gas

 

The problem specifically asks you to find the x, leaving you to figure out what y should be. Once you have y, then the proportion should be easy to solve for x.

[Bobby Strain]

So, this might be a trick question. So be sure not to leave out anything from the original problem statement. What you have shared above seems to be incomplete information.

 

Bobby

[romianne]

Profe, it's 125 mil.m3, not 0.05. Anyway, I am confused with the Sm3 and m3/d. Still I don't know how much water is there in 2.5 mil. m3/d (careful, not Sm3)

[romianne]

Thank you very much. It just seemed to be not right to imagine that there is 8750 kg of water in 125 mil. Sm3 same as in 2.5 mil. m3 at 5 MPa. Anyway, I solved it this way too but I was confused. Thanks again.

[Napo]

Romaine,

 

I think you calculation is only referential, you need take in count a Z (compresibility factor). you are working with 5 MPa, this is 725 psi (aprox. 51 bara) a high pressure, ideal gas equation is not recommendable.

 

A first aproximation can be Z = 1 - P/500, P in Bar(a), Z = 1 - 51/500 = 0,898

 

Other point is the water content at 5MPa and 15ºC, this is 350 kg/MMSM3, then a low pressure the value must be higher.

 

I attached a calculation with Sloan´s formula.

 

Napo.

 

 

 

 

Attached Files

•  Water in gas.xlsx   51.65KB   67 downloads

[Tinglaceen]

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