Aeration (ventilation)
The use of oxygen as oxidant is carried out for a long time to remove the hydrogen sulfide, when it has been identified as responsible for taste and odor of water, or to remove CO2 This can reduce the demand for reactive during correction processing (aggressiveness).
The aeration is further used to remove volatile organic materials that are in trace amounts in water to oxidize iron and / or manganese.
Thus, ventilation process can be defined as a physico-chemical oxidation process because it involves the transfer of physical phenomena of air, thus oxygen in water and optionally chemical reactions oxidation.
In a processing unit, the ventilation practice can be simple (aeration in a pond) or more complex (degassing tower by stripping).
NOTES.
Cascades (waterfall):
 Often these items are used to make up the differences existing between levels on the one hand, the implementation works of the station and also the level of the receiving environment. We took the opportunity to artificially create a system overflows by stairs, which has the effect of contacting water and air over a larger surface, and thus promote the dissolution of a certain amount of air in more efficient water that the mere transfer surface often improves ventilation by blowing air openwork stairs.
This system also eliminates hydrogen sulfide (odor).

 

Note: see in particular, on Hydro-Land site, Cascad program that calculates a cascade in order to achieve a partial or complete aeration of water (link, in french).

Degassing towers (stripping):
 The degassing towers are towers may contain:

  1. grids or plates pierced
  2. packing

which will facilitate the transfer of oxygen in water, or phenomena accelerate discharge of dissolved gases.
(According to méthose and carrier gas flow rates)

The packings are available in wide variety of plastics, ceramics or stainless steel.


Note: see in particular, in Hydro-Land site, DegazCO2 program that can calculate and design a round elimination of carbon dioxide, in order to achieve a partial or complete neutralization of aggressive water ( link ).

(use browser)