Pressing arrangement

A pressing arrangement comprising:

• a pressure vessel comprising a pressure cylinder and a first end closure and a second end closure;
• a furnace chamber arranged within the pressure vessel, the furnace chamber being at least partly enclosed by a heat insulated casing and arranged so that pressure medium is configured to enter and exit the furnace chamber;
• a plurality of pressure medium guiding passages in fluid communication with the furnace chamber and arranged to form an outer cooling loop within the pressure vessel;
• and
• a passive heat exchanger unit arranged within the pressure vessel and configured to absorb heat from the pressure medium, wherein the passive heat exchanger unit is entirely arranged within the pressure vessel and arranged such that the passive heat exchanger unit does not require any exchange of cooling medium with a source during operation of the pressing arrangement;
• wherein the heat insulated casing comprises a heat insulated layer and a housing at least partly enclosing the heat insulated layer, and wherein a part of the outer cooling loop comprises at least one first pressure medium guiding passage formed between at least a portion of the housing and at least a portion of the heat insulated layer, and arranged to guide the pressure medium after having exited the furnace chamber towards the first end closure to a space between the first end closure and the furnace chamber in which the passive heat exchanger unit is arranged, the passive heat exchanger unit comprising a plurality of inlets permitting the pressure medium having exited the furnace chamber to enter into an interior of the passive heat exchanger unit, the passive heat exchanger unit being configured so as to permit pressure medium to be guided through the passive heat exchanger unit towards at least one outlet of the passive heat exchanger unit, the at least one outlet permitting the pressure medium to exit the passive heat exchanger unit, wherein the plurality of inlets are arranged on a first side of the passive heat exchanger unit and the at least one outlet is arranged on a second side of the passive heat exchanger unit, wherein at least a portion of the first side of the passive heat exchanger unit comprises a plurality of perforations or openings distributed over the at least a portion of the first side of the passive heat exchanger unit, the plurality of perforations or openings constituting the plurality of inlets of the passive heat exchanger unit, wherein the plurality of inlets of the passive heat exchanger unit permit all of the pressure medium guided in the at least one first pressure medium guiding passage to enter into the interior of the passive heat exchanger unit, wherein the second side of the passive heat exchanger unit is facing in a direction towards an inner surface of the first end closure, and wherein each of the plurality of inlets of the passive heat exchanger unit is arranged above the heat insulating layer in a vertical direction and in a flow direction of the pressure medium in the at least one first pressure medium guiding passage towards the first end closure;
• wherein another part of the outer cooling loop comprises at least one second pressure medium guiding passage arranged to guide the pressure medium having exited the passive heat exchanger unit in proximity to an inner surface of walls of the pressure cylinder before the pressure medium re-enters into the furnace chamber.