Dryers for polycarbonate

Dryers for polycarbonate--The first of two dryer products licensed by Comet fromLanco, Hanau, Germany (see Industry News, p 36), is a dryer specifically designed for polycarbonates. The LTX Modular Dryers are single-bed desiccant dryers designed specifically for those polycarbonate resins used in the manufacture of CD-Audio, CD-ROM, CD-R and CD-MO, as well as DVD and recordable versions of the new optical disc format.

There are two models available: the LTX 25 can support two DVD injection molding machines or one CD machine; and the LTX40, which supports four DVD machines or two CD machines. LTX dryers have two built-in blowers for automatic loading and unloading of resin.

The LTX has a completely enclosed cabinet for dust-free production and it requires only 5 sq ft of floor space.

Comet's President, Tom Rajkovich, says the LTX will dry PC at less than 0.005% final humidity in about 3 hr. 

General-purpose dryers--The second of Comet's licensed dryers is the LTA Modular Dryer. These have large, horizontal desiccant beds (like a pizza oven, saysRajkovich) to provide a wider cross section for introduction and flow of the drying air.

The beds are 4 in. thick and have three chambers; Rajkovich says processors can use two while regenerating the third. With these flow properties, the dryers use blowers half the size of conventional desiccant dryers, thus reducing energy consumption by about 30%, he says.

The heat transferred from the warm, dry air into the resin is used for processing; and the heat generated for automatic regeneration of the desiccant is used to evaporate the water withdrawn from the granulate. Excess heat from the subsequent cooling phase is recycled for the drying process.

There are five LTA models with capacities ranging from 85 to 2000 cu ft/min. They can be used beside-the-press or configured for central operation. Rajkovich says pricing is competitive with conventional models. 

Comet Automation Systems, Inc.
Dayton, OH