NOVELTY - The device for fixed sealing between a fixed system (1) and a rotating system (2) of a thermolysis unit, comprises a sealing joint (42) and a controllable pressure unit (41), and is arranged on the periphery of the end of the rotating system located at the junction of the rotating system with the fixed system. The sealing joint and the pressure unit are attached to a fastener (3) arranged at the end of the fixed system. The fastener surrounds the fixed system with a diameter sufficient for fixing the sealing device, and provides support on the end of the rotating system.    USE - The device is useful for fixed sealing between a fixed system and a rotating system of a thermolysis unit, which is useful for upgrading hydrocarbon solids such as household wastes, automobile residual wastes, waste tires, industrial wastes, green wastes or other biomass.    ADVANTAGE - The device provides a cost-effective and good seal between a fixed system and a rotating system of a thermolysis unit thus regularly controlling the wear of the rotating system, and ensures good control of pressure exercised at any point on the circumference of the seal.    DETAILED DESCRIPTION - The device for fixed sealing between a fixed system (1) and a rotating system (2) of a thermolysis unit, comprises a sealing joint (42) and a controllable pressure unit (41), and is arranged on the periphery of the end of the rotating system located at the junction of the rotating system with the fixed system. The sealing joint and the pressure unit are attached to a fastener (3) arranged at the end of the fixed system. The fastener surrounds the fixed system with a diameter sufficient for fixing the sealing device, and provides support on the end of the rotating system. The pressure unit is inflatable and formed by an annular chamber made of flexible material. The sealing joint is a braid of glass fiber. The rotating element is rotary kiln, and a rotating dryer. The fixed element is a pipe.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of a sealing device.    Fixed system (1)    Rotating system (2)    Fastener (3)    Pressure unit (41)    Sealing joint. (42)