ex22 {phreeqc} | R Documentation

## Example 22–Modeling Gas Solubilities: CO2 at High Pressures

### Description

PHREEQC calculates the fugacity coefficient with the Peng-Robinson equation of state (Peng and Robinson, 1976) from the critical pressure and temperature, and the acentric factor of the gas in a gas mixture to obtain the limiting volume and the attraction factor in the Van der Waals equation. The fugacity coefficient is close to 1 when the total pressure of the gas phase is less than about 10 atm, and it can be neglected in the solubility calculation. At higher pressures, the effect can be substantial. At low pressures, the concentration of CO2 increases near-linearly with pressure. At 25 degrees C and pressures higher than 62 atm, the concentration increases more gradually because the fugacity coefficient drops rapidly. The example can be run using the `phrRunString` routine.

### Source

http://wwwbrr.cr.usgs.gov/projects/GWC_coupled/phreeqc

### References

http://pubs.usgs.gov/tm/06/a43/pdf/tm6-A43.pdf

### See Also

Other Examples: `ex10`, `ex11`, `ex12`, `ex13a`, `ex14`, `ex15`, `ex16`, `ex17`, `ex18`, `ex19`, `ex1`, `ex20a`, `ex21`, `ex2`, `ex3`, `ex4`, `ex5`, `ex6`, `ex7`, `ex8`, `ex9`

### Examples

    phrLoadDatabaseString(phreeqc.dat)
    phrSetOutputStringsOn(TRUE)
    phrRunString(ex22)
    phrGetOutputStrings()

[Package phreeqc version 3.4.10 Index]