In our recent blog, 'What's the Best Air Pollution Control Technology for My Process?', we examined the many factors that can impact a facility's choice of air pollution control equipment. When they are considering their air pollution control needs, it is important for the plant's engineering staff to discuss the application data with potential suppliers. This data will provide crucial details about the process operation, including as uptime, maximum VOC loading, and maximum air flow. With this data, the supplier will be able to predict energy usage, permitted emission rates, and other process operation data that may be critical to equipment design, and with this knowledge, they will be able to recommend options that meet the requirements for Best Available Control Technology (BACT) or Maximum Available Control Technology (MACT), ensuring that the facility's engineering staff will be able to meet or exceed their environmental goals or outcomes.
To provide more understanding of how we help our customers determine their BACT or MACT, we're looking at a few example scenarios here on the CPI blog.
Scenario 3: Catalytic Oxidizer
Your process has an airflow in the range of 500 to over 35,000 Standard Cubic Feet per Minute (SCFM) at ambient to very high process temperature (<600°F) and low to medium volatile organic compound (VOC) loadings, with a typical maximum of ~20% LEL (lower explosive limit). In this case, you may want to consider catalytic oxidation as your preferred technology.
Catalytic treatment of VOCs and other air pollutants works by reacting with the harmful air pollutants over a specially designed catalyst where VOCs are converted to CO2 and water vapor (H2O) at lower temperatures than thermal oxidation. These harmless byproducts, along with some extra heat from the destruction of the VOCs, are passed through a heat exchanger, where the gas stream's energy is transferred to the incoming exhaust. The heat exchange effectiveness can be as high as 75%.
Catalytic Oxidation systems represent cost-effective air pollution control alternatives when compared to thermal oxidation, due to their lower operating temperatures (400°F - 750°F). The lower operation temperatures and the ability to utilize a primary heat exchanger can reduce operating costs, save on fuel, and extend equipment life.
Advantages of this system include:
- Internal construction is primarily stainless steel, which means it can handle mildly corrosive exhaust streams.
- Cleanable without extensive maintenance.
- Relatively smaller footprint and weights less when compared to other control technologies.
- No moving parts.
- Used accross many aplications and for many different pollutants, including:
- NOx and CO abatement
There are a few drawbacks to these systems:
- Inability to handle processes which include
- Heavy metals
- Primarily thermal efficiency less than 75%
- The need for annual catalyst testing
In addition to the oxidizer, auxiliary heating systems such as secondary air to air recovery, air to water recovery, air to oil recovery, or a closed loop direct recirculation process can be used to further reduce operation costs.
Thank you for your interest in our blog series, 'Identifying Your Ideal Air Pollution Control Technology.' Below are links to all the blogs in this series:
At Catalytic Products International, we work to make sure that our customers are educated about the best solutions to their air pollution control needs and that they have the knowledge to continue to meet these needs as they grow and change. For more examples of how our expertise helps our clients find success, please read our Customer Testimonials.