Chemical - In-itu Chemical Oxidation
For feasibility testing, we use our own laboratory to execute batch tests. We also execute pilot tests on location, frequently with a result guarantee. We weekly sample groundwater and air flows to control, and if necessary adjust, the chemical process.
We apply the following chemical techniques:
- Ozone+peroxide and / or permanganate
- Persulphate (oxidant solution)
- Fenton’s Reagent (liquid oxidant)
When are techniques most effective?
Substances to be addressed by chemical oxidation, can be divided as follows:
- Saturated hydrocarbons (chlorinated) alkanes (CH): mineral oils, trichloroethane, dichloroethane, carbon tetrachloride, ethers and alcohols: MTBE, ETBE, TBA, TAME
- Unsaturated hydrocarbons (chlorinated) alkenes (C = C): Per, Tri, Cis and VC;
- Cyanide (C ≡ N).
- Styrene, phthalates
- (Chloro) phenols (e.g. PCP) and chlorobenzenes
- TNT, RDX and derivatives, nitro-anilines (explosives)
Polycyclic aromatic compounds: PAHs, PCBs and pesticides.
In some cases, these compounds are not fully chemically oxidized but, as it were, pre-treated (“predigestion”) in order to facilitate biological treatment. After all, soil has an intrinsic ability to biodegrade organic compounds.
Our main chemical oxidation technique is ozone in combination with hydrogen peroxide. Since we feel that the oxidant should be distributed as well as possible in (often) clayey or silty soils, a gas/liquid is particularly suitable.
The technique is based on creating tiny bubbles (ozone), to which hydrogen peroxide is added through special filters. In this process OH radicals occur, providing high oxidizing power. With this technique, it is not necessary to add primers or acids to the soil and therefore it can also be used in calcareous soils.
The technique is a highly flexible and continuous process that can be used in various ways, if needed in combination with complementary techniques. For example, switching to a biological treatment after the chemical phase is as easily administrated as injecting compressed air as pre-treatment or bacteria doses, all through the same system. Instead of hydrogen peroxide, a different type of oxidant may also be chosen.
- Sandy or silty soils (from k: 0.1 m / d)
- Compatible with multi-phase extraction and biological treatment
- Chlorinated Solvents, cyanides, MTBE, MO / BTEX