NESTEC didn’t invent the RTO, but we perfected it for wood pellet applications
“Regenerative incinerators can be used to reduce emissions from a variety of stationary sources. Generally, high flows (greater than 2.4 standard cubic meters per second (sm3/sec), (5,000 standard cubic feet per minute (scfm))), low VOC concentration (less than 1000 parts per million by volume (ppmv) applications are best suited to control with regenerative incineration systems (Gay, 1997). This type of incinerator is applicable in controlling VOC from metalworking and coating operations, automotive manufacturing, and forest and wood products manufacturing. Particulate matter (PM) and condensables which can clog the incinerator’s packed bed or poison the catalyst (for RCOs) would have to be removed by an internal filter or some pretreatment technology prior to the reactor chamber (Biedel and Nester 1995).” (Source: EPA)
Title V of the EPA’s Clean Air Act establishes a federal permit program for facilities which have the potential to emit:
- More than 100 tons per year of any regulated pollutant,
- 25 tons per year of hazardous air pollutants (HAP), or
- 10 tons per year of any single HAP (e.g. acetaldehyde, formaldehyde, methanol, or similar compounds used in wood pellet manufacturing)
All such facilities must apply for a Title V permit before the end of their first year of operation.
New Source Review is the Clean Air Act’s permitting program designed to limit emissions from large sources of air pollution by requiring a permit before a “major source” begins construction or undertakes a modification. For wood pellet mills, “major source” refers to a facility with the potential at full capacity to emit more than 250 tons per year of a regulated pollutant, rather than actual emissions.
In the wood pellet industry, Prevention of Significant Deterioration (PSD) requires limiting emissions that are achievable with the “best available control technology” (BACT). In practice, PSD is synonymous with utilizing BACT and its permitting process is meant to be demanding. Hence, most of the wood pellet industry has attempted to remain below the 250 ton per year threshold to avoid PSD (see Synthetic Minor).
Synthetic Minor Sources are facilities with the potential to emit significant pollutants that avoid stricter permitting by self-imposing “synthetic minor limits.” Doing so ensures they will be treated as a minor source by regulators, even if their full capabilities exceed that definition, so long as they comply with the minor limit (such as by reducing production or increasing efficiency to decrease emissions).
Hazardous Air Pollutants (HAPs) are airborne pollutants which the EPA considers especially toxic or carcinogenic. They are more strictly regulated under the Clean Air Act. HAP regulations apply to facilities which have the potential to emit more than:
- 10 tons per year of any single HAP, or
- More than 25 tons per year of all HAPs combined
Such facilities must apply for a Title V permit and utilize the maximum achievable control technology, a more rigorous standard than PSD’s best available control technology.
NESTEC’s Smarter Solution to Wood Pellet Pollution
NESTEC has established a comprehensive wood pellet program that evaluates manufacturing facility air emissions to reveal the best and most economical solution for any application. Our process can also recommend multiple solutions that allow customers to select a solution customized to their needs. A recent NESTEC system provided the facility with a unique alternate solution that netted more than $800,000 in savings over typical systems.
NESTEC’s wood pellet program includes:
- Evaluation of the wood source potential emissions based on the combined worst case makeup of soft and hardwood utilized in the pellet dryer, hammer mills, and pellet coolers
- Evaluation of the location of all sources and the potential for combining sources into a single system compared to multiple control equipment system, along with energy savings
- Evaluation of the RTO and/or RCO thermal energy recover (TER) efficiency and/or use of high temperature catalyst. along with online back out capabilities
- The benefits of NESTEC’s unique RTO design features include:
- Uniform airflow distribution nozzles for the heat exchange media
- Floating arch media supports with external beams (virtually eliminating thermal expansion problems during high temperature bake outs)
- Online bake out capabilities
- Auto Thermal Alignment Control with increased energy savings
- Simple payback analysis on optional features
NESTEC is presently providing air emission control systems for eleven pellet plants in Alabama, Georgia, Louisiana, South Carolina, and Mississippi. Two of the systems have been operating since 2013 with little or no fuel consumption.
If you have an application that requires air pollution control and energy conservation and want to select your solution from a list of options that will meet your specific needs: Contact NESTEC for a free process analysis and proposal.
Office: 610.323.7670
Jim Nester, CEO: jnester@nestecinc.com
Rick Reimlinger, Vice President: rick.reimlinger@nestecinc.com
Rodney L Pennington, PE, Vice President of Key Accounts: rpennington@nestecinc.com
William Holden, Aftermarket & Service Manager: wholden@nestecinc.com
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