Regenerative Thermal Oxidizers for Film Coating
Film coating lines run some of the highest solvent loads an RTO will ever see, loads high enough to sustain combustion largely on their own. The hard part isn't the high load, it's what happens the moment the line stops and that solvent drops to near zero. TANN designs a regenerative thermal oxidizer for film coating with a control strategy built around that exact swing.
Why Film Coating Needs an RTO Built for Abrupt Swings
Film coating exhaust typically carries very high solvent concentrations, high enough that the system can largely self-sustain combustion without much help from the burner. That's the easy part. The tougher control challenge shows up the instant the coating line stops, when solvent loading drops to near zero almost immediately. A regenerative thermal oxidizer for film coating has to manage that transition smoothly, every time the line starts and stops.
TANN addresses that swing with a staged control approach rather than a single control loop. As solvent loading drops, burner support, bypass damper position, and fresh air introduction all adjust together to bring the system down smoothly instead of overshooting on temperature. Controls respond to actual chamber temperature rather than a fixed timer, so the system reacts to real conditions whether the line is running at full solvent load or has just shut down.
TANN can configure the bypass approach to fit how a given line operates, and that same equipment also gives technicians a more practical path for routine maintenance access.
Film coating operations that use organic solvents generally fall under EPA's AP-42 Chapter 4 documentation for evaporation loss sources, including the section on polymeric coating of supporting substrates. A regenerative thermal oxidizer for film coating needs to hold up to that kind of scrutiny while still managing the load swings unique to this process.
What Makes Film Coating a Demanding RTO Application
A regenerative thermal oxidizer for film coating has to handle a few things at once:
- Very high solvent concentrations capable of largely self-sustaining combustion
- Solvent loading that can drop to near zero the moment the coating line stops
- A staged control approach that coordinates burner, bypass damper, and fresh air response to manage that swing smoothly
- Temperature-modulated controls rather than fixed-timer logic
- A bypass configuration matched to how the line operates
Built for What This Application Demands
TANN engineers and fabricates regenerative thermal oxidizer systems in-house at our Kaukauna, Wisconsin facility. For film coating, that means designing the control sequence around abrupt solvent swings from the start, not tuning around them after startup.
Staged Control Approach
TANN coordinates burner support, bypass response, and fresh air introduction as a system, so temperature steps down cleanly as solvent loading falls instead of overshooting.
Temperature-Responsive Controls
Controls respond to actual chamber temperature rather than a fixed schedule, so the system adjusts in real time whether the line is running at full solvent load or has just shut down.
Bypass Configured to the Line
TANN configures the bypass approach to fit how a given line operates, which also gives technicians a more practical path for routine maintenance access.
High solvent load isn't the hard part of film coating. It's the moment the line stops and that load disappears. The control sequence, not the raw destruction capacity, is what keeps the system stable through that swing.
What Film Coating RTOs Are Up Against
Knowing what stresses a regenerative thermal oxidizer for film coating helps facilities set the right operating procedures, and helps them spot a system that wasn't designed for this kind of swing in the first place.
Self-Sustaining Solvent Loads
Solvent concentration can run high enough to sustain combustion with little or no burner support. Controls still need to keep that self-sustaining condition inside a safe temperature range.
Abrupt Line Stops
When a coating line stops, solvent loading can fall to near zero almost immediately. Without a staged response, that swing can cause temperature overshoot or an unnecessary trip.
Control Coordination
Managing burner, bypass, and fresh air response together takes more coordinated control logic than a steady-load process typically requires.
Bypass Damper Wear
Bypass dampers cycle frequently in this application, so damper actuators and seals see more duty than in a steady-state process.
Media Fouling
High solvent concentrations can carry residue into the ceramic heat exchange media over time, raising pressure drop and lowering thermal efficiency if left unaddressed.
Combustion System Drift
Like any continuously operating oxidizer, combustion components and controls can drift over time. Temperature deviations affect destruction efficiency, fuel use, and compliance reporting, regardless of the process being served.
TANN Supports Your System for the Long Term
A regenerative thermal oxidizer for film coating needs its control sequence to keep working reliably every time the line starts and stops. So TANN stays involved from initial engineering through the full operating life of the system.
Engineering and Fabrication
TANN engineers and fabricates every RTO in-house at our Kaukauna, Wisconsin facility, with the control response to solvent swings designed in from the start.
Installation and Startup
TANN provides installation support, commissioning, and operator training, including guidance on how the control cascade should behave through line stops and startups.
Annual Inspections
Scheduled inspections check dampers, actuators, media, and controls before wear from frequent cycling turns into an unplanned issue.
Control Sequence Support
TANN's service team can review and re-tune the burner and bypass damper sequence if line speeds or solvent formulations change over time.
Media and Damper Service
TANN can support cleaning or replacement of media and bypass damper components that see extra cycling in this application.
24/7 Emergency Response
TANN's service team is available around the clock. When an unplanned issue affects your emissions control system, our team can troubleshoot remotely and mobilize qualified technicians to your facility when you need them most.
Warning Signs a Film Coating RTO Needs Attention
In this application, trouble usually shows up first at the transitions, when the line starts or stops. Catching it early avoids bigger problems down the line.
Performance Indicators
- Temperature overshoot or undershoot when the line stops or starts
- Bypass dampers that are slow to respond or hunt around a setpoint
- Rising pressure drop across the media beds
- Increasing fuel consumption without a change in line speed or solvent use
Operational Observations
- More frequent high-temperature trips during line stops
- Bypass damper actuators showing visible wear or lag
- Destruction efficiency results trending the wrong way, even slightly
- Any system that hasn't had a documented inspection in over 12 months
Ready to discuss your film coating line's emissions control requirements?
Whether you're planning a new regenerative thermal oxidizer for film coating, or trying to get ahead of control issues around line stops on an existing system, TANN is ready to help. Our engineering team designs the control sequence first, so your system stays stable through every swing.