Process for pulverising polyurethane, polyurea and/or polyurethane/polyurea materials in a roller mill
AssigneesBayer Aktiengesellschaft, Maschinenfabrik Hennecke GmbH
InventorsJoachim Wagner, Karl Peltzer, Jurgen Wirth
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Abstract
When pulverising polyurethane, polyurea and/or polyurethane/polyurea materials in a roller mill with at least two rollers (2,3) rotating at different circumferential speeds, a very economical method of operation is achieved by returning the coarse fraction falling freely out of the roll slit (4) to the roll slit (4) and stripping the fine material adhering to the roller (3) with the higher circumferential speed and discharging it separately from the coarse fraction.
Claims8
A process for pulverizing polyurethane, polyurea and/or polyurethane/polyurea materials in a roller mill in which at least two rollers rotate at different circumferential speeds comprising:
- a) passing precomminuted material to be milled into a roll slit formed by the rollers to form a coarse fraction and a separate sheet of fine fraction;
- b) collecting said coarse fraction falling freely downstream from said roll slit;
- c) returning said coarse fraction to said roll slit;
- and
- d) scraping said sheet from one of said rollers so as to produce a plurality of discrete particles for further processing.
Dependencies are inferred from the claim text.