NOVELTY - The device comprises a reactor (10) divided into four reactor sections through which the biomass to be treated is continuously conveyable, where each reactor section is tubularly arranged. A first reactor section is arranged for heating the biomass, the second reactor section is arranged for carrying out a polymer process, a third reactor section is arranged for carrying out a maturing process, and the fourth reactor section is arranged for cooling the biomass. A first and second heating-/cooling device (21, 22) receiving thermo-fluid is arranged at the reactor wall.    USE - Device useful for continuous hydrothermal carbonization of biomass.    ADVANTAGE - The device ensures simple and efficient hydrothermal carbonization of biomass without loss of valuable nutrients and heat energy.    DETAILED DESCRIPTION - The device comprises a reactor (10) divided into four reactor sections through which the biomass to be treated is continuously conveyable, where each reactor section is tubularly arranged. A first reactor section is arranged for heating the biomass, the second reactor section is arranged for carrying out a polymer process, a third reactor section is arranged for carrying out a maturing process, and the fourth reactor section is arranged for cooling the biomass. The length of the second and third reactor sections is selected so that the average retention time of the biomass in the second reactor section is 1-8 hours and in the third reactor section is 2-14 hours. A first and second heating-/cooling device (21, 22) receiving thermo-fluid is arranged at the reactor wall and coupled with second heating-/cooling device so that a part of the thermo-fluid of the first heating-/cooling device is supplied to the second heating-/cooling device. One of the heating-/cooling device is arranged as a heating-/cooling mantle surrounding the reactor. The heating-/cooling mantle comprises two chambers, which are thermally separated to each other. The chambers of the heating-/cooling mantles are running parallel to longitudinal axis of the reactor. The first chamber is arranged as heating device and the second chamber is arranged as cooling device. The reactor comprises reactor segments, which are coupled to each other so that a pressure-tight coupling of the reactor segments is reachable. The individual reactor segments are coupled to each other with a conveyor. The reactor comprises a supply device arranged at inlet opening (11), and an introducing device arranged to the supply device for introducing the biomass present in the supply device into the reactor. The supply device comprises a funnel-shaped inlet, an inlet side locking device (80) and inflow side locking device (81). The connection devices are openable, where two locking devices are arranged at the outlet opening. The first locking device is openable synchronic to the inlet side of the locking device. An agitator and/or crushing device is arranged in the inlet. A pressure sensor (61) is arranged to the supply device and is coupled with the inlet side locking device and/or with inflow side locking device. The reactor segment is arranged rotatable to the characteristic longitudinal axis. The reactor comprises an outlet opening for the reception of the intermediate product, where two locking devices are arranged to the outlet opening. An INDEPENDENT CLAIM is included for a method for continuous hydrothermal carbonization of biomass.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic representation of a device for continuous hydrothermal carbonization of biomass (Drawing includes non-English language text).    Reactor (10)    Inlet opening (11)    Heating-/cooling device (21, 22)    Pressure sensor (61)    Locking devices. (80, 81)