of different organic containing industrial liquid wastes. This technology is applicable to remove the organic content from the solution in every case, where the traditional incinerator techniques are not economical or cannot be used because of the environmental protection rules. There is no pH limitation for the application of the technology; it can be used even in acidic or highly caustic media.
conductivity plasma zone is being formed between the surface of the submerging electrodes and the solution by the effect of either ordinary network frequency or high frequency alternating electric current of sufficient voltage, causing the organic content of the solution to undergo thermal and chemical decomposition. The decomposition takes place due to both the UV radiation and the extremely high temperature (15,000- 20,000 oC) of the plasma. The decomposition of the organic material can be intensified further by oxidative environment provided by adding appropriate oxidizing agent. The decomposition of the organic materials takes place in several steps. The
final product of the decomposition is mostly carbon dioxide, nitrogen and water, while the inorganic salt content of the solution remains unchanged.
During the operation of the technology the wastewater is kept at boiling
temperature, therefore it can as well be concentrated on demand to a required extent by means of controlled condensate withdrawal. If the waste has sufficient electrical conductivity and pH, it basically needs no solid chemicals added; therefore the solid content is not increased. This is one of the advantages comparing to the other wastewater treatment technologies.
The underwater plasma technology has several applications. Some successful
applications are listed here:
Industrial technologies:
– Decomposition of Fe-EDTA in boric acid containing wastewater at Paks
Nuclear Power Plant;
– Elimination of radioactive Co isotopes from a high boric acid containing
liquid waste at Paks Nuclear Power Plant;
– Decomposition of methanol in aqueous waste solution at Hungarian Oil
Refinery (MOL).
Co-isotope removal technology at Paks NPP Plasma equipment for MOL
Pilot scale technologies:
– EDTA decompositor for Korea Electric Power Research Institute;
Laboratory scale technologies:
– Application of high frequency (10-100 kHz) alternating current for
treatment of EDTA containing waste solution at AREVA;
– Decomposition of liquid wastes of different chemical decontamination
techniques;
– Treatment of the wastewater of MEROX technology (highly caustic) in
oil industry;
– Wastewater of Pharmaceutical Factory, CIPLA India;
– Treatment of wastewater originated from a Belgian explosive material
producer, Antwerp. The waste solution contained different nitrophenolic
compounds;
– Treatment of the waste solution originated from different drug production
at EGIS, Hungarian Pharmaceutical Factory.
