Basf Aktiengesellschaft

Badische Anilin- & Soda-fabrik Aktiengesellschaft

Ernst Kissel

Werner Hoerauf

Ernst Guenther

Guenter Valentin

Eckart Neumann

Ernst Dietrich

Eberhard Schaefer

Hermann Linge

In a process for drying and heating nylon granules, in which the granules flow downwards through a vertical zone, hot inert gases which are free from molecular oxygen are passed in counter-current through the granules and the cooled granules are then intermittently discharged in part-streams, the improvement wherein the wet granules, or a suspension of the granules in water, are fed into the zone at the top, the granules are deposited as a layer, the water is led away, the layer of granules is then transferred into the next-lower part of the zone, the granules are there allowed to flow under gravity downwards through the zone, and inert gases which are free from molecular oxygen are passed in countercurrent upwards through the granules at from 70 to 200.degree. C, with the proviso that the inert gas, before leaving the zone, is passed through the deposited layer of granules, in the lower part of the zone the granules are divided into part-streams over the entire cross-section of the zone, these part-streams are cooled and the granules are passed intermittently, but simultaneously over the entire cross-section of the zone, into a discharge zone, with the proviso that the discharge zone is only partially filled, as well as an apparatus for carrying out the improved process.

Process and apparatus for drying and heating nylon granules

The continuous countercurrent extraction of polylactam granules with hot water in an extraction zone for the removal of monomer and/or oligomers, the extraction zone being subdivided into subzones by at least one heating zone. The density of the extract-containing water differs by at least 0.0002 between the subzones.

Extraction of polylactams

An extraction tube for the continuous removal of low molecular weight components of polylactam granules by means of hot water by the countercurrent principle of operation, the water being fed upwardly and the granules downwardly, the tube being provided with inlets and outlets for the granules and the water and exhibiting baffles within the tube, wherein there is provided, within the tube, a heat exchanger which

Extraction tube for polyamides

Growing community of inventors

Ludwigshafen, Germany

Ernst Kissel