The Process and Water Quality Specialists

Air Stripping
Air Stripping
  • 1 air stripping
Theory of Air Stripping

The fundamentals of each process can be described as follows. 

Air stripping involves transfer of contaminants from the water to the air phase.  The assumptions in the development of the design equations for packed tower aeration include

  1. Steady state conditions prevail in the tower
  2. Air flow rate and water flow rate are constant along the column
  3. Air and water flow are counter-current
  4. Contaminant concentrations are small in both the air and water streams
  5. No reaction occurs that results in the destruction or formation of the contaminants being removed.

The design equations for tower diameter and packing height for an air stripping tower to meet treatment targets are well developed in the literature (see for example, Crittenden et al., 2005, for citations to the relevant literature).  There are several models available for air stripping design calculations.  One challenge associated with air stripping as a cost effective solution is the requirement to treat the off-gas.  Air stripping is commonly applied to strip carbon dioxide from RO treated water, which is dead soft and often contains high levels of dissolved CO2.