Henry's Law

Henry's Law, one of the gas laws, states:

At a constant temperature, the amount of a given gas that dissolves in a given type and volume of liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid.

 

Dissolved Oxygen

Bio-enhancing contaminated groundwater with O2 to raise dissolved oxygen levels is commonly performed to create or enhance a natural aerobic biodegradation of contaminants. At standard ambient temperature and pressure (25ºC, 1bar), the solubility of dissolved oxygen in fresh water is approximately 39 mg/L.

The solubility of oxygen in water is dependent on temperature and pressure:

  • Temperature: solubility increases with decreasing temperature
  • Pressure: solubility increases with increasing partial pressure of oxygen in accordance with Henry's law
 

Henry's Law:

H = C / P
where,

H = Henry's constant for O2 in water at a given temperature and pressure ( H is different for every gas, temperature, and solvent)
C = concentration of O2 in water
P = Partial pressure of O2

Practical Implications for O2 bio-enhancement remediation techniques:

The solubility of DO in water will increase with depth to contaminated groundwater plume (i.e. depth is proportional to increased pressure and decreased temperature)


 

Practical implications for use of the Waterloo Emitter: