A method for thermally drying wood using a drying installation comprising at least one drying chamber, wherein said method comprising:
- Acquiring metrological data and parameters of the wood to be dried by measurement via metrological means;
- Activating means of supply of CO2 configured to saturate the drying chamber with CO2 and having a circulating gas mixture;
- verifying that the CO2 saturation in the circulating gas mixture is sufficient to initiate a drying cycle by checking via means of measurement of CO2/CH4 in a discharge duct;
- Activating means of heating to adjust the humidity of the wood by heating when a sufficient measured CO2 saturation is achieved.
- If the humidity of the wood exceeds 30%, heating with a temperature limit according to a first setpoint temperature T1, according to a selected temperature gradient G1 in order to extract the free water from the wood to be dried and activating means of circulation;
- If the humidity of the wood is less 30%, heating with a temperature limit according to a first setpoint temperature T2, according to a selected temperature gradient G2 in order to extract the bound water from the wood to be dried and activating the means of circulation;
- stabilising the temperature of the CO2 circulating in the drying chamber in a first phase when a humidity of less than or equal to 30% is measured, activating the means of recycling and subsequently increasing the temperature of the CO2 circulating in the drying chamber in a second phase until the measured humidity of the wood reaches a chosen intermediate target value Hi, the means of heating being activated so that reheating is carried out with a limit temperature defined by a second setpoint temperature T2 of 120° C. according to a selected temperature gradient G2, and as a function of the specific drying profile of the wood to be dried enabling the bound water to be extracted from the wood to be dried;
- Maintaining the humidity of the wood to be dried by deactivating the means of recycling and varying the activity of the means of heating to reduce the temperature of the heating chamber in a first phase, down to a third stabilisation setpoint temperature T3 chosen according to a temperature gradient G3, when the average humidity of the wood measured via the means for measurement of the humidity of the wood reaches the chosen intermediate target value Hi, unless one of the measured humidity values of the wood is greater than Hi+A %, A being a selected value, said setpoint temperature T3 being maintained for a selected period of time until the measured humidity value of the wood initially greater than Hi+A % is stable and within a range of values less than Hi+A %;
- Deactivating the means of heating, in order to reduce the temperature of the heating chamber in a second phase, when the measured average humidity of the wood reaches the final target humidity value Hc.