The device (1) has a container connected to a heat exchanger (6) via a circulation line (5) opened into the container with entry and exit points (5a, 5b). A barrier (8) e.g. inner container, blocking the exit point of the circulation line from a solid phase is arranged in the container. The barrier is arranged at distance (A) to a wall of the container, and the entry point is arranged in a lower area of the container in a solid stage including a nozzle (10). A degassing device is provided at the container. The exit point is separated from an interior of the container by the barrier.
