Idea of Decontamination 

 

The contaminated fluid phase of the ground(Hydrocarbon – Water mixture) shall be picked up by extraction pipes (suction pipes) lowered into extraction wells distributed over the area in adequate layout. The suction pipe has about 50 cm free movement up and down, in order to achieve sufficient depression at diverse groundwater levels. In order to avoid the extension of the contamination to lower, clean soil layers, the lowest end of the extraction pipes must not be deeper than the deepest level of the ground contamination.

 

By means of lowering the water to equal level the contaminated soil layers, earlier covered by water can be aerated. During the discharge of the fluid a depression develops around the perforated well pipe, generating an air streaming. It enables the aeration of the zone of groundwater level alterations and the unsaturated zone, accelerating the biological decompositionof the hydrocarbons bound to soil grains. Due to the vacuum effect the increased oxygen-input, together with the exhaust of the carbon dioxide generated by the decomposition of HC stimulate the development and propagation of the bacterium flora. This kind of increase of biological decomposition is characterized by the increase of the oxygen consumption and of the CO2 output. The reduction of bound CH-contents can be followed by the measurement of the Total Paraffin Hydrocarbons-contents of the soil.

 

 

Kind of Contaminations to be cleaned


The 4 forms of gasoline contamination to be handled:
- Free Hydrocarbon-phase on the surface of the groundwater
- Mixed and dissolved phase in the groundwater
- Hydrocarbons adsorbed to the soil in the saturated and in the unsaturated zones
- Vapors in the pores of the soil


Principles of Decontamination


The advantage of this two-phase extraction is the possibility of simultaneous handling of
both saturated and unsaturated zones without intensive lowering of water level.
The system extracts directly the free hydrocarbon phase as well, as the contaminated water
and the vapors of unsaturated zone, while the biological Hydrocarbon decomposition can be
accelerated indirectly by the aeration.


Main Technical Features


Maximal treatable water capacity: 3,5-7 m3/hours
Capacity of vacuum pump: 7,5 kW
Maximum Power consumption: 10 kW
The equipment is placed into a standard 20 feet container
Supervision free operation, remote control through GSM