Study On The Equipment And The Characteristics Of Eucalyptus Path In Vacuum Drying

The comprehensive utilization of small-diameter wood in conventional drying is low.This paper adopts vacuum drying for small diameter logs.With diameter of 100mm and initial moisture content of 50%Eucalyptus Path dried to 10%as standard wood,the Eucalyptus Path vacuum dryer,loading capacity of which is 2.0m~3,had be designed by theoretical design and calculation of the heating system, the shell strength during the vacuum drying process.This dissertation is studied on the Eucalyptus Path drying characteristics,which include the critical dimension and the distribution of temperature and moisture content in vacuum drying.The comparison of the vacuum drying and conventional drying of Eucalyptus Path and semi-post-path is conducted in a pilot plant.(1)When the heat dissipation area of the heaters is larger than 4.68m~2 and the cycle air volume is larger than 6.38m/s,the Eucalyptus Path vacuum dryer can meet the process.(2)The difference rate of drying rate is 10%as the critical point.When the absolute pressure is 0.02MPa and temperature is 80℃,60℃,the critical aspect ratio of Eucalyptus Path sample,the diameter of which is 100 mm,is 2.87,1.73 respectively.(3)The average drying rate of Eucalyptus Path with diameter of 100mm in critical length is similar to the length middle in Wood drying process.The moisture content of the length direction is larger than the the diameter direction in the range of critical moisture,and water evaporates from the end.(4) The vacuum drying rate of Eucalyptus Path and semi-post-mortem material,with the absolute pressure of 0.02MPa,temperature of 60℃and the diameter and length of 80～140mm×80mm,to the conventional drying rate is 3.8,3.4 respectively.The drying quality is good.