The most widely used treatment for the removal of volatile organic compounds (VOCs) in industrial emissions is regenerative thermal oxidation.
The presence of VOCs in emissions requires a treatment that removes them as they are dangerous compounds. VOCs are classified into 3 groups, depending on their effects on people and the environment:
VOCs are all those organic compounds that exist in a gas or very volatile liquid state at ordinary room temperature. In practice VOCS are all those organic compounds that have a vapor pressure equal to or higher than 0.01 kPa or an equivalent volatility in the particular conditions of use at 20ºC. VOCs usually have less then twelve carbon atoms in their chain and contain other elements such as oxygen, fluoride, chlorine, bromine, sulphur or nitrogen.
Although there are more than 1,000 different VOCs, the most abundant in the air are methane, toluene, n-butane, isopentane, ethane, benzene, n-pentane, propane and ethylene. They are compounds are generated in industrial processes in which organic solvents (such as acetaldehyde, benzene, aniline, carbon tetrachloride, 1,1,1-trichloroethane, acetone, ethanol, etc.) are used.
A regenerative thermal oxidizer is ideal for:
Condorchem Envitech designs and builds regenerative thermal oxidizers according to each specific application, with the most common equipment being:
Regenerative thermal oxidation is applicable to all processes liable to produce VOC emissions, which are very numerous, and generally belonging to the following industrial sectors:
Regenerative thermal oxidation destroys VOCs by converting them into CO2 and H2O. The process is carried out inside towers filled with ceramic material in which the pollutants are oxidized at 750ºC. The system has a thermal efficiency greater than 95%, such that the consumption of gas to maintain the temperature is reduced.
This equipment has a system of conical closure valves, thanks to which a very high purification efficiency is achieved and the risk of leakage of untreated air is avoided. Thanks to this system the equipment can remain closed during the night shift or weekends, thus maintaining a high temperature and therefore a rapid launch, with low consumption by the equipment.
The regenerative thermal oxidation is very versatile as regards the flow to be treated, between 2,000-100,000 Nm3/h, which is ideal for medium-high concentrations of VOCs (0.3-10 g/Nm3) and optimal for a great variety of VOCs.