Regenerative catalytic oxidizer (RCO)
Regenerative catalytic oxidizer systems combine the advantages of regenerative heat exchangers with those of catalytic oxidation. They are used to reduce pollutant levels in exhaust air that is not heavily contaminated and to minimize odors.
- Lower operating expenditure than conventional regenerative thermal oxidizers. Lower natural gas consumption and reduced fan output.
- Long catalyst life of five or more years
- Low NOx levels – mainly flameless operation
- Highly efficient where VOC levels are low
- Increased volume when converting an RTO to a RCO
- High levels of efficiency combined with low operating expenditure
When volatile organic compounds (VOCs) exist in a solvent-laden exhaust air stream of a manufacturing process, they are either collected for recovery for potential re-use or they are destroyed. When the solvents have little or no recovery value or where there are concerns for disposal of toxic compounds, a destruction technology from Dürr such as thermal or catalytic oxidation may be the best option.
Our regenerative catalytic oxidizers (RCOs) combine the low operating temperature of catalytic oxidizers with the heat storage and recovery characteristics of a regenerative thermal oxidizer (RTO). This combination provides the lowest operating cost VOC oxidation technology available for applications with low VOC concentrations.
Operating principle RCO
The RCO is a regenerative thermal oxidizer with a catalyst above the heat exchanger bed. The catalyst material is either a base metal or a precious metal that gives rise to a chemical reaction with incoming volatile organic compounds (VOCs) or hazardous air pollutants (HAPs). This lowers the required reaction temperature. As a result, less heat and therefore less external energy are needed to convert the pollutants. The temperature in the combustion chamber can be reduced from 850°C to below 500°C. After the pollutants have been converted, the clean exhaust air can leave the system.
Application areas RCO
RCO systems can be used in a wide variety of industries because of the range of optional equipment available to accompany them. These systems can be found in the chemical, pharmaceutical, timber, and rubber and latex industries.
- Rubber & Latex
Technical specifications RCO
RCO systems can effectively treat process flows from 5000 Nm3/h to over 80,000 Nm3/h containing the following pollutants at concentrations ranging from <1 g/Nm3 to 10 g/Nm3:
- VOCs (non-methane hydrocarbons)
- Carbon monoxide (CO)
The efficiency levels of the systems range from 95% to more than 98%.
The RCO is similar in design to a conventional RTO system. However, it is fitted with an additional catalyst and operates at a lower combustion chamber temperature. The efficient recovery of heat by the ceramic heat exchanger enables the RCO to treat exhaust gases with low pollutant concentrations of just under 1 g/Nm3 without the use of additional primary energy sources.
RTO to RCO retrofit
While your existing RTO system may have been designed for optimum thermal efficiency at the time it was manufactured, new advances in media and catalysts give us more options for many exhaust streams that lend themselves to catalytic technology. In some cases, by converting from RTO to RCO, our customers can recognize a 50% reduction in fuel usage. Many actually achieve an operating condition (self-sustain) with no additional fuel required for oxidation.
The RTO to RCO conversion is a relatively simple conversion and often works in combination with your existing ceramic media, and can typically be accomplished with only a few days of equipment down-time.
Contact Dürr to find out about the efficiencies we can offer with an RCO or RTO to RCO conversions.