Environmental Engineering Reference
In-Depth Information
Figure 15.12.
Column stripping process [GER 96]
15.5.2.5.
Pumping or extraction triple phase (slurping)
This process consists of selective pumping of the floating organic contaminants
(of density below 1) in the following forms:
-
in free form floating above the aqueous capillary fringe;
-
in dissolved form in the saturated zone;
-
in gas form in the unsaturated zone.
The system of slurping is composed of a filtering well (or extraction switches)
and a rigid tube (or canes) placed inside the needle. The higher tube/cane opening is
connected to an extractor in order to apply a depression.
Initially, the depression created allows the introduction of a cone of folding back
essential to recovery of the pure products. Once the folding back is stabilized on the
level of the tube/cane opening, a mixture (water/produced pure product) is extracted
at the short-nap cloth of the water level, i.e. air if it is above. This process has links
with several techniques: folding back-creaming, the extraction of phases and
(bio)venting.
