Drying of plastic powders - case study


Courtesy of AVA GmbH u. Co. KG

'Continuous strippers' for polymer powder manufacturing

Often in the production process for plastic powders, a solvent such as methanol or alcohol is used, which then has to be completely evaporated again at a later stage. Depending on the consistency of the product, evaporating the solvent is not always particularly easy and the drying process often ¬nishes with residual moisture content in the range of 3% - 5%.

At this point, evaporation has to be supported by means of adding pre-heated nitrogen, saturated steam or hot air, the so called “stripping” process, in order to achieve a residual moisture content of nearly 0%. AVA supplies a “continuous stripper” especially for this application in an ATEX-conform, explosion-proof design, with a special agitator, which supports the percolation of the plastic powder with the carrier medium, but also guarantees a good heat transfer by means of the cylinder jacket.

Due to the geometry of the agitator, a high level of back-mixing is achieved and the retention time in the dryer is increased. This guarantees a constant temperature and humidity in the entire dryer as well as a homogenous and dry end product.

Customer comments

No comments were found for Drying of plastic powders - case study. Be the first to comment!