Plasma Air - Plasma Catalysis Technology
Air treatment using plasma-catalysis technology(gaseous cleaning). Plasma-catalysis technology, was first developedin the 1980’s for air treatment plants in space vehicles. It is now one of the most effective and cost-efficient modern gas treatment technologies. Plasma-catalytic technologyis based on two ways of decomposing gaseous contaminants into elementary compounds: plasmo-chemical and catalytic. Due to their combined effect, organic substancescomposed of oxygen, hydrogen and carbon are converted into entirely harmless compounds comprising carbon dioxide and water, which are expelled ingasesous form. This process may be expressed by the following equation:
This process may be expressed by the following equation:
CxHyOz + hν → CO2 +H2O
Lets consider the impact of decomposition methods separately:
Plasma-chemical air treatment techniquefordecomposinggaseous contaminants
It is well known that plasma is a gas with ionized molecules and atoms. Plasma consists of many components: electrons of different energies, positive and negative ions, neutral particles, as well as excited atoms and molecules. The process of convertingharmful substances takes place as follows:
contaminated air flows through the chemical reactor of the air cleaner where gaseous harmful substances are destroyedunder the influence of a low-temperature plasma, and other physical and chemical effects.
Futhermore, as a result of these influences molecules, atoms and radicals become excited affecting the efficiency of the of catalytic treatment stage.
Catalytic air treatment technique of decomposing gaseous contaminants
The catalytic air treatment technique produces a deep oxidation of conversion products, resulting from the passage of air through the plasma-chemical reactor. This method uses a low temperature catalyst, which due to plasma-chemical step starts to operate effectively in a temperature range from 20 to 50 0C.
The plasma catalytic technique for removing
harmful gaseous substances is unique in that it allows a thorough conversion of a whole range of toxic compounds to CO2 and H2O, even at indoor room temperature. This air purification technology is also interesting because pathogenic microflora in the air is also suppressed at the same time as gas treatment takes place. The air is disinfected to a significantly greater degree than possible with ionizing air filters.
The plasma catalytic technique solves the problem of air cleaning (gas cleaning):
- with a minimum of catalyst (free of precious metals);
- at minimum temperature (from 20 0С);
- with minimum power requirement;
- and allows the amount of treated air to range from 100 m3/hour up to 100 000 m3/hour or more.
One of the areas in which it has clear advantages over conventional gas cleaning techniques is in industries, which use small or medium sized manufacturing equipment: small heating, thermal, melting furnaces, paint-spraying booths, smokehouses, stoves for heat treatment of food products, etc. These benefits arise due to low capital and operating costs for plasma-catalytic air cleaners and the high efficiency of gas treatment achieved.
One more interesting sphere of application of plasma-catalytic air treatment technology is usage of air cleaners in air ventilation systems.This applies especially to big industrial cities and centers. Traditional air treatment is mainly limited to the use of oil and fibrous air filters, that effectively (at least 99%) clean dust and aerosols from the air. However, the problem of treating of harmful gases remains open. Plasma-catalytic technology provides deodorisation for offices and other premises.