Materials containing vaporizable substances are exposed successively in at least two treatment chambers (10, 13, 14), which can be closed off with respect to each other, to a series of decreasing pressures and increasing temperatures. The vaporizable substances are exhausted separately from each treatment...http://www.google.se/patents/US5595483?utm_source=gb-gplus-sharePatent US5595483 - Method and apparatus for thermal treatment of materials containing vaporizable substances
