A large American papermaking company faced a plant shutdown due to a sudden failure of the scrubber which controls emissions of airborne pollutants. Weak precipitated calcium carbonate solution clogged the scrubber nozzles. Engineers felt that they could prevent nozzle clogging by reducing the solids content from 1200 ppm to 300 ppm at 300 gpm flow capacity.

Kason engineers suggested using a 60 in. diameter VIBROSCREEN Circular Screen Separator equipped with a 325 mesh screen to separate solids larger than 45 microns as the slurry passes through the screen. The papermaker didn't want to shut down the plant because huge sums of money would be lost. On the other hand, engineers at the plant felt skeptical about Kason' s suggestion. To minimize the commitment to it, Kason offered to rent the VIBROSCREEN to the papermaker. With a promise of building the VIBROSCREEN in a day, the papermaker accepted and dispatched a truck to bring it to the plant.

They found that even though many of the particles in the slurry had diameters in the 10 micron range, the VIBROSCREEN's vibrations induced the small particles to agglomerate, forming particles larger than 45 microns in size.

After a week's use, the engineer who consulted for the papermaker reported that the VIBROSCREEN successfully prevented the scrubber nozzles from clogging, averting a costly plant shutdown that had been anticipated. And after a month, the papermaker purchased the VIBROSCREEN.

Screen Tips - Volume 9, Number 3 Winter 1994