TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: A heat conducting- and/or heat-storing thermal fluid, preferably water is provided in the region between the inner container and the pressure vessel, where the thermal fluid at least almost completely fills an intermediate space between the outer wall of the inner container and the inner wall of the inner space of the pressure vessel. The inner container is immersed in the thermal fluid, where the level of the thermal fluid is below an opening of the inner container. The outer shape of the inner container is at least substantially corresponding to the inner shape of the inner space of pressure vessel. The inner container is positively fit, and/or at least approximate circumferential gap is formed in the same distance between the wall of the inner spaces, and/or the inner container and/or the inner space of the pressure vessel are formed substantially in cylinder-like or cylindrical shape with a circular cross section, with a circular aperture at a first end side. The cross section of the opening at least substantially corresponds to the inner cross section of the inner container and the inner space. A dome-shaped, preferably semi-spherical curvature, preferably a round bottom is formed as a base, at an end side, which is opposite to the opening, and runs parallel, preferably at least substantially perpendicular to common longitudinal central axis of the inner container and/or the inner space. The pressure vessel comprises the opening as an access to the inner space, where the opening is arranged on the upper side of the pressure vessel and is formed for passing, preferably moving the inner container and/or the opening of the pressure vessel is closable with a cover, preferably a lid. The cover is detachably connected to the pressure vessel, where the cover and/or an additional cover, preferably a cap is provided for the opening of the inner container. A laterally pivotable lifting device, preferably a crane is provided for the insertion of the inner container into the inner space of the pressure vessel or for the removal of the inner container from the inner space of the pressure vessel. The inner container is moved through the opening of the pressure vessel, where the inner container can be raised to a level lying above the opening of the pressure vessel by the lifting device. The inner container comprises at least one fastening device, preferably a holder for releasable coupling of the lifting device, and/or the inner container comprises a device for shutting off in the inner space of the pressure vessel. The pressure vessel is heatable on the wall side, where at least the inner walls of the pressure vessel can be heated or cooled. The pressure vessel comprises a heating jacket, and the interior space surrounds at least one or many sides as a hollow body and/or as a line, preferably a spiral pipe in the region of the wall of the pressure vessel and/or a liquid thermal medium, preferably thermal oil flows at least partially through the heating jacket. At least one circuit is provided for the thermal medium and/or a feeding device, preferably a pump is connected with the heating jacket for the thermal medium via at least one line, preferably a hose or pipe. At least one insulated buffer storage or tank for the thermal medium and/or a heating- and/or cooling device is provided for heating or cooling of the thermal medium, and at least one circuit for the thermal medium, inner space and/or the inner container are connected with at least a device for pressure relief, preferably at least one blow-off device or a pressure relief valve and/or a blow-off tank for relieving pressure. Preferred Method: The inner space of the pressure vessel is heated via the inner wall of the pressure vessel, where the inner wall is heated by the heating jacket adjacent to the inner wall, preferably the cavity in the wall of the pressure vessel and/or lines, preferably spiral pipes and/or hoses in or on the wall of the vessel in the inner space and/or within the wall, by passing thermal medium through the lines. The inner space of the pressure vessel is filled at least in part with a thermal fluid, preferably water, preferably in the intermediate space surrounding the inner container, and the inner container is at least predominantly heated via the wall and/or the inner container is at least partially filled with a liquid, preferably water for heat transfer between the pressure vessel and the inner container. The inner container with all the necessary reaction educts, preferably with the organic material, water and additives, including a catalyst comprising citric acid is filled outside the pressure vessel. The inner container is discharged after removal from the pressure vessel and cleaned prior to refilling, and/or an additional inner container filled with the reaction educts is employed for the quasi-continuous implementation of the hydrothermal carbonization in the direct exchange of inner container containing the reaction products in the pressure vessel. At least a portion of the reaction educts, preferably the organic material is homogenized before filling into the inner container, preferably crushed and/or is mixed with the remaining reaction educts and the carbonized material taken after the hydrothermal carbonation from the inner container is filtered, dried and/or compacted, and includes carbon or charcoal. The inner container is employed by at least one lifting device arranged at least substantially above the pressure vessel, preferably a crane, and is removed through the opening of the pressure vessel upwardly out of the inner space and downward. At least a portion of the organic material, water and/or additives, preferably at least one catalyst present in the inner container is inserted into the inner space of the pressure vessel, and/or the hydrothermal carbonization is carried out in the inner space of pressure vessel in gas-tight and/or pressure-sealed manner. At least the predominant part of the carbonized material and water, i.e. the reaction products present in the inner container is removed from the pressure vessel. A hot thermal medium is fed at least in part from an intermediate store, preferably a hot oil tank into the cavity or the lines for heating the inner space, and heated by a heating device, and/or a hot or cold heat medium is used for maintaining the temperature during the reaction or for cooling during the removal of the inner container, where the excess heat energy is stored and/or released into the environment. The pressure vessel is closed and heated by stored heat energy. The hydrothermal carbonization is carried out under discharge of excess heat energy, and/or the inner container is again removed, replaced, emptied, cleaned and is refilled.