A cup of coffee is only as good as the roasting operation behind it.
For coffee roasters, one of the most important decisions to make is how to remove harmful pollutants produced during the coffee roasting process.
In our last post, we examined different product alternatives to afterburners that can create a cleaner roast. This time, we will re-visit afterburners and look at the specific benefits and drawbacks of each type. Each afterburner is offered by Inproheat Industries through our line of Smoke Dog afterburners.
Here’s a closer look at each afterburner.
Catalytic Afterburner / Thermal Oxidizer
The Pros:
- First of all, catalytic afterburners operate on natural gas or propane.
- They offer low to medium operating costs due to low gas prices and the advantage of a catalytic advantage.
- Additionally, they are highly adaptable to larger coffee roasting operations.
- Compared to traditional afterburners, catalytic models also use less gas.
- Where emissions are concerned, this model eliminates nearly all smoke, odor, and VOCs.
- In environmentally-strict areas like Los Angeles or Seattle, catalytic afterburners are effective compliant pollution control devices.
- Finally, low NOx can be enabled on catalytic models.
The Cons:
- The catalytic element creates backpressure, which negatively affects the roasting system.
- Over time, catalytic elements age and lose their ability their emission control efficiency.
- Furthermore, replacing catalytic elements is a large capital expense.
- Another consideration is that the weight of catalytic afterburners makes roof-mounted installations challenging.
- There is a high up-front purchasing cost for catalytic models.
- Lastly, advanced venting and electrical efforts are needed, along with industrial controls.
Traditional Afterburner/Thermal Oxidizer
The Pros:
- Traditional afterburners operate on natural gas or propane.
- Additionally, they boast medium operating costs and low gas prices.
- For larger operations, traditional afterburners are highly flexible.
- They eliminate over 99% of smoke, odor and VOCs.
- They comply with environmentally-strict areas like Los Angeles and Seattle.
- Traditional afterburners can be built with low NOx capabilities.
- There is zero backpressure, which allows for a consistent roasting operation.
- Traditional models require low maintenance.
- They carry long lifespans.
The Cons:
- Traditional afterburners produce combustion byproducts like CO2.
- As well, there is a medium upfront purchasing cost.
- Additionally, they leave a large footprint.
- Finally, they require moderate venting and electrical installation efforts to go with basic industrial controls.
Recuperative Afterburner/Thermal Oxidizer
The Pros:
- Recuperative afterburners use natural gas or propane for operation.
- They also boast low operating costs thanks to low current gas prices.
- The larger the roasting operation, the greater the increase for investment returns.
- They eliminate over 99% of VOCs, smoke, and odor.
- Recuperative afterburners comply with strictly-regulated cities like Seattle or Los Angeles.
- They can feature low NOx capabilities.
- Recuperative models produce no backpressure, which delivers a consistent roast.
- They need only a medium amount of maintenance.
- Furthermore, recuperative afterburners possess long lifespans.
- The return on investment for recuperative afterburners is as low as 1.5 years.
- Lastly, they produce less combustion byproducts than traditional afterburners.
The Cons:
- They carry higher up-front costs to purchase.
- For smaller sizes, the return on investment is noticeably lower.
- Recuperative afterburners are heavy and are not intended for all rooftops.
- Owners must plan for the expense of eventually replacing a recuperative afterburner’s heat recovery banks.
- Finally, advanced venting and electrical efforts are required for installation along with advanced industrial controls.
Ultimately, it’s up to the roaster to decide the most important factors for their operation. Roaster size, area of operation, budget, and future capacity plans are just a few critical considerations. At Inproheat Industries, we work with coffee roasting clients to determine exactly which type of Smoke Dog afterburner is best.
Ready to adopt your own Smoke Dog afterburner? Talk to our sales department!