Abstract: The invention provides a process for the extraction of solid materials using a solvent and the apparatus for implementing same. In this process, the solvent/solute separation is provided by vaporization without special precautions in the apparatus, the vapor phase thus obtained being subjected to centrifugal separation in the separator.

Abstract: The extraction tank (1) carries an endless screw (13) on its upper portion and a conveyor belt of endless screws (17) on its lower portion to ensure its charging and discharging respectively, a complementary means employing a screw (7) with a vertical shaft on the upper portion and a shutter (22) mounted at the top of an evacuation tube (35) on the lower portion making it possible to obtain at each of these levels a plug (36, 37) of material that is tight to the fluids under pressure admitted into the tank.Application to vegetable material extraction units for the production of essential oils.

Abstract: The invention provides a process for producing essential oils by plant hydro-distillation including the following steps:(a) loading the plants continuously into a still where they are processed counterflow wise with steam,(b) continuous unloading of the exhausted plants,(c) recovery of the latent heat of distillation and condensation of the steam by means of a gas in a condenser,(d) drying of the exhausted plants by contacting with the gas, in a drying installation,(e) combustion of at least a part of the dried exhausted plants in a boiler and use of the combustion heat for producing steam.