Combined Timber Drying Method

This paper presents the results of investigations of the moisture and temperature distribution in drying by the conduction method, by means of a radio-frequency electromagnetic field, and by the combined method of heating at a low pressure. The rate of drying by the combined heating method is twice higher than in conduction heating and 1.5 times higher than in radio-frequency heating at the same energy input to the wood. The finite moisture content of the wood in drying by the combined method is much lower than in drying by the other methods, and the moisture gradient in the thickness of the specimen does not exceed 5%. On the basis of the results of investigations a pilotproduction vacuum drier with a loading volume of 1 m3 has been created.