VP · Technology
Vapor Permeation
Vapor permeation runs the same dense membrane chemistry as pervaporation, but on a vapor-phase feed. That means lower mass transfer resistance and higher fluxes, with the trade-off that the feed must be vaporized first. Used where the feed is already in the vapor phase (reactor exhaust, dryer offgas) or where the highest possible flux is needed.
What it solves
Performance you can size against.
The outcomes below come from commissioned systems and verified pilots, not theoretical limits. Every number is independently testable on your own feed.
- VOC capture from process exhaust
- >98%
- Recovers solvents from reactor and dryer offgas at ambient pressure.
- Higher flux than pervaporation
- 2 to 5x
- Compact systems for high-throughput applications.
- Compatible with existing process
- No need to condense and re-vaporize; we tap directly into vapor lines.
How it works
The working principle.
A vapor feed is fed across the membrane at low pressure. The target component sorbs into the dense membrane and diffuses across. A vacuum or chilled sweep on the permeate side condenses the recovered fraction. Non-permeating components return to process or vent.
Performance envelope
Specs and operating range.
For preliminary sizing only. Production sizing is always validated against your specific feed.
- Operating temperature
- 60 to 120°C
- Operating pressure
- 1 to 3bar absolute
- Solvent capture rate
- >98%
- Permeate purity
- >99.5wt%
- Flux vs pervaporation (same membrane)
- 2 to 5x
- Specific energy
- 80 to 150kWh/m³ feed equivalent
- Membrane life (typical)
- 2 to 4years
How we compare
VP vs the alternatives.
Where Vapor Permeation wins, where it does not, and where the alternatives are honestly the better fit.
| Trait | Vapor Permeation | Pervaporation | Activated Carbon Recovery |
|---|---|---|---|
| Feed phase | Vapor (taps directly into vapor lines) | Liquid (requires liquid feed) | Either, but vapor preferred |
| Flux | High (2 to 5x pervaporation) | Moderate | N/A (batch capture, not flux) |
| Recovery for reuse | >98%, recovered as condensate | >98%, recovered as condensate | Bed regeneration recovers most; quality varies |
| Continuous operation | Yes | Yes | No (load and regenerate cycles) |
| Best fit | Reactor exhaust, dryer offgas, high-throughput VOC capture | Liquid solvent dehydration, azeotrope breaking | Low-volume, intermittent VOC streams |
Feed phase
Vapor Permeation
Vapor (taps directly into vapor lines)
Pervaporation
Liquid (requires liquid feed)
Activated Carbon Recovery
Either, but vapor preferred
Flux
Vapor Permeation
High (2 to 5x pervaporation)
Pervaporation
Moderate
Activated Carbon Recovery
N/A (batch capture, not flux)
Recovery for reuse
Vapor Permeation
>98%, recovered as condensate
Pervaporation
>98%, recovered as condensate
Activated Carbon Recovery
Bed regeneration recovers most; quality varies
Continuous operation
Vapor Permeation
Yes
Pervaporation
Yes
Activated Carbon Recovery
No (load and regenerate cycles)
Best fit
Vapor Permeation
Reactor exhaust, dryer offgas, high-throughput VOC capture
Pervaporation
Liquid solvent dehydration, azeotrope breaking
Activated Carbon Recovery
Low-volume, intermittent VOC streams
Where it's deployed
Industries that use this process.
Vapor Permeation fits some sectors better than others. The industries below are where we have shipped multiple systems.
Engineering FAQ
Questions engineers ask.
The questions we hear weekly. If you have a different one, send it with your consultation request and we will answer it directly.
When should I use vapor permeation over pervaporation?
Can it handle hot, dirty exhaust streams?
What is the minimum VOC concentration that makes economic sense?
Can vapor permeation be combined with pervaporation?
Have a feed that VP
might fit?
We will pilot before we promise. Send us a sample and a target outcome. If the technology fits, we will tell you what to expect; if it does not, we will tell you that too.