Apparatus and method for heat treatment of wood

A wood thermal treatment apparatus, comprising:

• a cell comprising a thermal treatment chamber adapted to house a wood mass to be treated, wherein the cell comprises an air circulation jacket arranged outside the thermal treatment chamber, which is adjacent to the thermal treatment chamber and fluidly isolated from the thermal treatment chamber by at least one thermally conductive partition wall so that air flowing in the air circulation jacket does not flow in the thermal treatment chamber, wherein the air circulation jacket comprises an inlet collector for introducing the air into the air circulation jacket and an outlet collector for extracting the air from the air circulation jacket;
• a heating and cooling system for heating and cooling the thermal treatment chamber, adapted to take a heating operating configuration and a cooling operating configuration;
• wherein the heating and cooling system comprises:
• a recirculation duct which in the heating operating configuration is connected between the inlet collector and the outlet collector so that an airflow, which is introduced into and extracted from the air circulation jacket, passes in the recirculation duct, wherein in the heating operating configuration, the recirculation duct and the air circulation jacket form a closed circuit;
• a heating unit configured to heat air flowing in the recirculation duct by combustion of wood waste resulting from wood processing;
• and
• flow diverter means configurable to open the closed circuit in the cooling operating configuration of the heating and cooling system.

A wood thermal treatment method, comprising:

• arranging a wood mass to be treated in a cell comprising a thermal treatment chamber adapted to house the wood mass to be treated, wherein the cell comprises an air circulation jacket arranged outside the thermal treatment chamber, which is adjacent to the thermal treatment chamber and fluidly isolated from the thermal treatment chamber by at least one thermally conductive partition wall so that air flowing in the air circulation jacket does not flow in the thermal treatment chamber;
• heating an air mass by combustion of wood processing waste and introducing the heated air mass into the air circulation jacket, causing the heated air mass to pass through a recirculation duct operatively connected to the air circulation jacket to heat an interior of the thermal treatment chamber and carry out a wood thermal treatment at a temperature in a range of 180° C.-230° C.;
• and
• at the end of the wood thermal treatment, cooling the wood mass by opening the recirculation duct to introduce air drawn from an external environment into the air circulation jacket, and progressively lowering the temperature inside the thermal treatment chamber.