Photoionisation (PI) represents an exciting “new” technology in the odor control business. It is relatively new to North America but has been successfully used in Germany (and elsewhere) for over 10 years for odor control, mostly in wastewater treatment, but also in many other industrial applications.
Photoionisation is based on the application of UV light and a catalyst. The first part of the process mimics natural reactions that take place in the upper atmosphere by the interaction of air and UV light coming from the sun. The principles are fairly straightforward. Odorous air passes through a chamber where it is exposed to intense UV light. The UV light creates free radicals, (O- 2, OH-, O3, etc.), that immediately begin oxidizing the odour-causing compounds.
The air then passes to a catalyst, where any remaining odorous compounds are adsorbed and are broken down by the constant0 flow of free radicals coming with the air from the UV section. The reactions that take place also indicate catalytic activity as one of the by-products is native sulfur – the classic catalytic Klaus reaction. Thus, the catalyst acts as both a catalyst and “buffer”.
- Small footprint
- can handle very high concentrations of odorous compounds (100's of ppm of H2S).
- Particularly effective on all reduced sulfurcompounds.
- Easily handles spikes
- Operates over a wide temperature range (-30 oC - > 70 oC).
- Low maintenance requirements (1/2 day/ year)
- No water or chemicals required
- Very stable process
- Can easily be turned on or off and begins working immediately
- Low energy demand