Three main external factors which affect the speed of wood drying equipment
Three main external factors which affect the speed of wood drying equipment
1, Temperature
Temperature is a major factor affecting wood drying speed. When temperature increment
, wood moisture increased pressure to reduce the viscosity of the liquid consisting of water, and promoting mobility and the diffusion of water in the timber; the ability to dissolve copper wet drying medium to improve and accelerate the rate of evaporation of surface moisture of the wood. But it is worth noting that if the temperature is too high, it will cause the wood cracking and deformation, reducing mechanical strength, color, etc., so it should be properly controlled.
2, Humidity
Relative humidity is an important factor affecting wood drying speed. At the same temperature and air velocity, the higher the relative humidity, the larger the partial pressure of water vapor in the medium, the surface of the wood was more difficult to evaporate the water medium, the slower drying rate; the relative humidity is low, fast evaporation of surface moisture, surface moisture content decreased, moisture gradient increases, increasing the moisture diffusion and fast drying. But the relative humidity is too low, it will cause cracking and dry honeycomb and other defects occurred even worse.
3, Air circulation speed
Air circulation speed is another factor affecting wood drying speed. High-speed airflow can damage the saturated vapor boundary layer on the surface of the wood, thereby improving between the media and wood heat and mass transfer conditions to speed the drying speed. For hard when dry wood or wood moisture content is low, the internal water timber movement determines the drying rate; by increasing the flow rate to accelerate large media surface moisture evaporation rate of no practical significance, but will increase the moisture gradient, increasing produce dry the risk of defects. So, hard dry wood does not need a big media rotation speed.