RTO operating cost is strongly influenced by airflow, VOC heat release, thermal recovery, startup frequency, heat loss and the amount of supplemental fuel required. Thermal recovery is important, but it is only one part of the overall energy balance.
How an RTO reduces fuel demand
During each cycle, ceramic media stores heat from the treated gas. The airflow path then switches, allowing incoming exhaust to pass through the hot media before entering the oxidation chamber. This regenerative process reduces the energy needed to raise the process air to the operating temperature.
Factors that increase RTO fuel consumption
- High airflow with low VOC concentration and little heat release.
- Frequent startup and shutdown cycles.
- Large heat loss from ducting, housing or stack components.
- High humidity or cold inlet air.
- Dust, oil mist or condensables that increase pressure drop or require bypass and pretreatment.
- Unstable process operation that forces conservative burner or bypass settings.
Can an RTO operate without supplemental fuel?
Some applications may approach autothermal operation after startup when the VOC heat release is sufficient. This must be confirmed through a project-specific heat balance. Fuel is normally required during startup, low-load operation and conditions where the exhaust does not provide enough heat.
What data is needed for an energy estimate?
A preliminary estimate should include total and minimum airflow, VOC composition, average and peak concentration, inlet temperature, humidity, operating hours, startup frequency, thermal recovery target, site utilities and required emission limits.
See the RTO sizing guide, compare RTO and thermal oxidizer options, or send your process data for review.
