What is a Catalytic Recuperative Oxidizer?
A Catalytic Recuperative Oxidizer (often called catalytic oxidizer) destroys pollutants like Hazardous Air Pollutants (HAPs), Volatile Organic Compounds (VOCs), and odorous emissions that are often discharged during industrial processes.
Catalytic oxidizers achieve high VOC destruction efficiency by heating and maintaining a polluted airstream at temperature (typically 600 to 650F) for a set “dwell” time as it passes through catalyst material. The lower operating temperature of a catalytic oxidizer results in much lower fuel use than thermal recuperative oxidizers. VOC destruction efficiency can reach 99+%. Catalytic oxidizers can operate with an integral heat exchanger for fuel savings, or without a heat exchanger for capital cost savings.
Catalytic systems perform well in clean applications with no halogens, sulfurs, silicone, or particulates. These systems have a long life because they operate at a much lower temperature than thermal recuperative oxidizers.
On this page:
The Three T’s of Catalytic Oxidizers – Time, Temperature and Turbulence
Note: Gas hourly space velocity (GHSV) is sometimes substituted for “time” when describing catalytic system performance. GSHV is the technical term for the ratio of treated airflow to catalyst volume for catalytic units. It is a critical value determining the performance and life expectancy of a catalytic system. High GHSV values represent lower performance and shorter catalyst life.
Still unsure which technology is best? Call us or request a quote. Our cost-benefit analysis for your specific project will compare multiple technology options, recommend the most cost-effective option and clearly explain the trade-offs of each option.
How does a catalytic oxidizer work?
A pollutant-laden airstream is pushed through the oxidizer, usually with a system fan (1). When equipped with an air-to-air heat exchanger, the flow of air will pass through the air-to-air heat exchanger (2) to preheat the air before entering the burner/combustion chamber (3). In the combustion chamber, the air is heated to a sufficiently high (>600F) temperature and then passes through the catalyst material (bed) (4) where VOCs are destroyed. The hot, cleaned air then continues through a hot pass of the heat exchanger (if heat exchanger is utilized) (5). The cooled, clean air is then exhausted to the atmosphere (6).
Advantages and disadvantages of catalytic systems over other technologies such as regenerative thermal oxidizers are discussed more completely here Selecting an Oxidizer.
Types of Oxidizers
There are several different kinds of oxidizer technologies. If you’re unsure which system is best for your application, we can help.
Direct Fired Thermal Oxidizers (DFTO)
Direct fired thermal oxidizers (aka afterburners) represent the most basic thermal oxidizer technology. DFTOs have the lowest capital/maintenance costs compared to other systems, and are very effective in treating process air with high VOC concentrations.
Regenerative Thermal Oxidizers (RTO)
Regenerative Thermal Oxidizers are the most widely used air pollution control technology today. They have the lowest operating cost compared to other thermal oxidizer systems, with high reliability and long service life. Learn more about regenerative thermal oxidizers or check out our used RTO inventory.
Recuperative Thermal Oxidizers
Recuperative thermal oxidizers have an integrated air to air heat exchanger that uses hot treated air from the combustion chamber to pre-heat inbound process air. Because of this heat recovery, less fuel is consumed by the burner.
Regenerative Catalytic Oxidizers (RCO)
Regenerative Catalytic Oxidizers operate similar to RTOs (see above) but include a layer of catalyst impregnated ceramic media, making them even more fuel efficient than RTOs. RCOs work well for low-VOC process airstreams (below 16%) and have a long service life.
VOC Rotary Concentrators
VOC Rotary Concentrators are air pollution control systems that pre-condition the airstream before it goes to a paired oxidizer for VOC destruction. VOC concentrators work by absorbing VOCs from high-volume, low-VOC process air, then releasing the concentrated VOCs into a smaller vapor stream that is treated in a thermal oxidizer. Learn more about VOC rotary concentrators.
Who Uses Catalytic Oxidizers?
Catalyitc Oxidizers are used by manufacturers in a wide range of industries and applications. The Kono Kogs team has experience with practically every possible oxidizer application across many industries around the globe.
Some of the Processes Catalytic Oxidizers are Used to Treat Include:
- Fiberglass gel coating
- LCD panel production
- Semiconductor fabrication
- Steel furniture paint booths
- Wood furniture surface finishing
- Rotogravure printing
- Flexographic printing
- Heatset web offset printing
- Label printing
- Rubber production
- Automotive paint processes
- Medical products film coating
- Material coating
- Surface coating
- Wood composite fabrication
- Chemical processing/manufacturing
- Spiral core winding
- Foil stamping
- Flow coating
We have an in-depth understanding of every process airstream our systems are used to treat. Explore our thermal oxidizer case studies or contact us with questions about the different technologies available for your specific application.
How Much does a Catalytic Oxidizer Cost?
The cost of a catalytic oxidizer addition includes the initial capital investment in the equipment as well as the operating and installation costs. Buying a pre-owned, fully refurbished catalytic oxidizer from Kono Kogs can save you 40% or more in capital costs compared to the cost of new, with comparable guarantees and warranties.
Kono Kogs recommends carefully thinking through the Total Cost of Ownership (TCO) before making a purchase. A catalytic oxidizer system with a low capital cost might not represent your lowest TCO in operation over time. As a rule of thumb, consider a two-year period when calculating the total cost.
Capital Costs Include:
- Commissioning (start-up)
Operating Costs Include:
- Compressed air
- Maintenance service
Both capital and operating costs can vary widely between different catalytic oxidizers. Some TOX technologies have fuel costs 5-10x higher than other systems. A Catalytic Oxidizer with a low initial cost could have a higher TCO over two years compared to that of a Catalytic Oxidizer or Regenerative Thermal Oxidizer.
Kono Kogs is happy to provide a cost-benefit analysis for your project. We’ll compare multiple technologies, explain the trade-offs of each option, and give you our professional recommendation on the most cost-effective system.
Questions to ask when considering a catalytic recuperative Oxidizer (CATOX)
- Is a catalytic oxidizer the most cost-effective oxidizer solution for my airstream?
- See Selecting an Oxidizer for guidance or call us for guidance
- Are catalyst poisons (halogens) or contaminants (silicone, phosphorus) in the airstream?
- If present, consider a different oxidizer technology
- A heat exchanger is a cost-effective option for most applications
- For catalytic systems, plate or shell & tube heat exchangers will perform well
- Is there a potential for particulates?
- Catalytic systems do not handle particulates well; consider other technologies
- VOC concentrations over 16% will require special consideration
Kono Kogs Knows Everything about Catalytic Oxidizers
Kono Kogs is the world’s leading supplier of used Thermal Oxidizers, sold as-is or fully refurbished. We also offer thermal oxidizer services including turnkey installation, repair, preventive maintenance, and upgrades. Our team has over 150 years of combined experience, and a 100% success rate in meeting performance guarantees. Whether we can help you get more years out of your existing system or find a replacement, we look forward to the challenge!
Kono Kogs is the world’s leading supplier of used catalytic recuperative oxidizers, sold as-is or fully refurbished. Reach out to us for a quote or more information.
Reach out to us for a quote or contact Kono Kogs for more information.