Influence of Steam Drying Process on Wood Mechanical Properties. Results of influence of gas-steam mixture drying process on mechanical properties of material are presented. Wood species, namely oak (Quercus L.), beech (Fagus L.), pine (Pinus L.) and spruce (Picea K.) from the northern part of Pomerania region in Poland, were subject of air-steam mixture drying process in a laboratory kiln especially arranged for that reason. Measurements of the global coefficient of elasticity and bending strength for steam dried and air dried samples, as a reference, allowed to reveal the effect of wood steam drying on mechanical properties of wood. It has been recognized that air-steam wood drying causes a small decrease of the mechanical properties of the wood. While the color changes have been observed directly after process, changes in mechanical properties have to be measured. During experiments time of drying process was shorten and satisfactory results were obtained.
The high cost of fossil fuel and soaring consumer interest have encouraged people in the wood industry to look for faster and more energy-efficient methods to dry lumber. The air-steam mixture as medium of drying process was used in a laboratory kiln especially arranged for that reason. Experimental rig is based on automatic control system. At the time of drying measurements of the internal temperature, wood temperature, moisture content and humidity can be performed. During experiments time of drying process was shorten and satisfactory results were obtained.