The CCS in Contrast with Wet ESP
Electrostatic Precipitators – Cloud Chamber technology is often confused with
electrostatic precipitation (ESP) because both use electric charge. Aside from this superficial similarity,
the technologies are strikingly different. Only the Cloud Chamber system uses charged droplets.
CCS only charges the water droplets. The billions of droplets are collectors.
ESP is a process commonly used for treating particles. It works by charging the particles
in the gas stream, causing them to migrate through an electrostatic gradient to metal plates for
collection. In general, dry ESPs are not suitable for submicron particle applications because
of particle size, resistivity, back corona, re-entrainment, and other issues. However, wet ESPs that
use water to condition the particles and rinse them from the collectors can be effective on certain fine particulate. Usually multiple stages are required and acceptable results are sometimes simply not
attainable on certain pollutants. Corrosion is a common problem, as are channeling and dry spots.
Loading density and the presence of coarse particles create problems. Great caution must be
taken in design and operation because of the presence of both very high voltage and amp draw.
Arcing and space charge effects prove to be serious limitations.
Fine particulate in conventional wet ESP.
In contrast, Cloud Chamber technology removes submicron particles simply and effectively.
Rather than attempting to charge the particles and move them to a distant collector, the Cloud
Chamber Scrubber charges only the collector (that is, the water droplets) and moves the collector
to the particles. When a particle passes within 20 microns of a droplet, the droplet charge induces
a dipole charge on the particle, which causes the particle to move the short distance to the droplet.
There is no need to pre-charge the particles or create a high voltage drift gradient. Because the
particles are not charged, treatment efficiency with the CCS is not sensitive to changes in the
particle concentration and composition. There is no “space charge” effect.
Another sharp contrast between wet ESP and CCS is power consumption. Wet ESP has a high power
draw that increases proportionally to the number of particles, while the CCS requires only
6-10 watts per 1000 cfm regardless of particle loading. According to vendor literature, wet ESP
uses 1000 - 3000 watts per 1000 cfm. While the CCS uses more energy to circulate water,
the total system energy draw is dramatically less than wet ESP.
A final distinction between the two technologies is that, unlike ESP systems, CCS systems
remove gases at efficiencies equal to or greater than those of packed bed wet scrubbers.
Additional Advantages of the CCS
- Wet ESP efficiency minimizes in the submicron range because of limitations inherent
in corona field charging and diffusion charging.
- The submicron particle size region has greatest impact on controlling opacity.
- Particle capture by diffusion in the ultrafine region is theoretical, requires combination
of high ion density and long exposure time.
Hinds, Aerosol Technology, Second Edition, 1999.
- Wet ESP, for best function, is often preceded by a device for removing particles over 2.5 micron.
- Wet ESP often requires removal of acid gases to prevent accelerated corrosion by electricity.
- Wet ESP is not efficient for acid gas removal, usually needs to combine with a wet scrubber.
- CCS is highly efficient: captures acid gases; coarse, fine, ultrafine, and condensable PM.
- CCS is much more energy efficient; especially when wet ESP is combined with another device.
Wet ESP often requires a second device. CCS does not.
To demonstrate the effectiveness of the CCS for your application,
Tri-Mer conducts an active Pilot Plant Program.
Have a potential application? Tell Us About It . . .
We Can Help You with Some Guidelines.
For more information contact:
Kevin Moss (801) 294-5422
kevin.moss@tri-mer.com
CCS HOME / CASE STUDIES / CCS NEWS / CLOUD CHAMBER SCRUBBER BULLETIN /
CCS or Fabric Filters / Baghouses? Considerations and Comparisons /
HISTORY / PILOT TESTING / CCS Q&A / CONTACT US / TRI-MER HOME
Tri-Mer Corporation
1400 Monroe Street
P.O. Box 730
Owosso, MI 48867; USA
Phone: (989) 723-7838
Fax: (989) 723-7844
salesdpt@tri-mer.com
© Copyright 2007 Tri-Mer Corporation
Website designed by Marketing Services Inc. |
