DETERMINING THE MINIMUM HEIGHT OF THE EMISSION SOURCE FROM CAMERA FOR DRYING BEECH WOOD
The process of chamber drying of wood is accompanied by a prolonged exposure to wood of heat and moisture. As a result of this effect, the ligno-carbohydrate complex of wood decomposes with the release of various harmful substances, the most dangerous are furfural and formaldehyde. The amount of furfural and formaldehyde in the spent drying agent depends on the initial moisture content of the wood, duration and drying mode. The degree of environmental impact of harmful substances depends on the drying regime, the height of the release of the drying agent from the chamber, and environmental conditions. The low emission height of the spent drying agent with harmful substances leads to exceeding the maximum permissible concentration of harmful substances in the surface layer. Therefore, the aim of research is to reduce the concentration of furfural and formaldehyde in the surface layer. The studies were carried out on beech wood growing in the Krasnodar region. It was found that the maximum amount of furfural and formaldehyde is released from beech wood during drying by mild conditions. The largest amount of harmful substances is released from beech wood in the first stage, when free moisture is removed, regardless of the drying mode. It is possible to lower the value of near-ground concentration at the border of the sanitary zone by correctly choosing the height of the source of dispersion of harmful substances. The work determines the height of the source of emissions of harmful substances from the drying chamber, depending on the drying regime of beech wood and climatic environmental conditions. In the warm season and at dangerous wind speeds (less than 1 m / s), the height of the source of emission during drying of beech wood should be the greatest, in the cold - the smallest. Based on the studies performed, recommendations are given for the placement of exhaust pipes and their heights for drying chambers, taking into account the volume of simultaneously dried wood.