density of gas and liquid in two phase flow

[cuppajoe]

How to calculate the density of the gas phases in a gas-liquid flow?
I have the following information for this stream:
O2: 20kg/h
Water: 80kg/h
Temp: 30C
Pressure: 10kpag

 

[Latexman]

Use the ideal gas law. PV = nRT. n/V = rho = P/RT.

Good Luck,
Latexman

 

[pierreick]

Hi,
Using Canary Software available on Internet, PR EOS @ 303.15K ,110 KPa A:
Material phase is 12.75% mole vapor;
Vapor density: 0.044 kgmole/m3
liquid density:55.151 kgmole/m3
vapor molecular weight:31.533 kg/kmol
liquid molecular weight:18.015 kg/kgmol

Good luck
Pierre

 

[LittleInch]

Your issue will be how much gets absorbed by the water. How is this gas being added to the liquid. If as bubbles it will get absorbed faster than a side stream.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[ReonArd]

You can use this spreadsheet which calculates average density in a two-phase flow:

SitePad

Sitepad1 Suite of spreadsheets designed to aid in process calculations commonly used in the oil & gas and petrochemical industries. References and equations are provided, no registration is required. Guideline: Yellow cells: Editable input (including unit selection) Green cells: Calculated...

sitepad1.wordpress.com

-> select "Pressure Loss of Two Phase Flow in Circular Rough Piping"

 

[georgeverghese]

Oxygen solubility in water may be neglected for O2 density calcs as solubility is very low. O2 in vapor phase would be water saturated.
Stream temp = 30degC

ppH20 = 0.039bar abs = 3.9kpa abs
ppO2= 110-3.9 = 106.1kpa abs

Mole fraction H20 in vapor = 3.9/110=0.0355, mole fraction O2 = 1-0.0355 =0.965
Vapor mole weight = (0.0355*18)+(0.965*32) =31.52

Vapor density = MW*P/ZRT, where z = 1 for low pressure
=31.52*110/1/8.314/(273+30) =1.376kg/m3 = 1.376/31.52 kgmole/m3 = 0.0437kgmole/m3

which matches simulator result from @pierre