榆木热风干燥器的设计OA

Using elm wood as raw material,the drying characteristics of it during hot-air drying were investigated,and the kinetics characteristics of hot air drying for elm wood were analyzed.The volatile organic compounds(VOCs)generated during the drying process were measured,and a rotary dryer with a processing capacity of 10 t/h was designed based on the biomass drying characteristics.The results showed that during hot air drying of elm wood,the higher the hot air temperature,the lower the initial moisture content of biomass,and the smaller the biomass particle sizes,the shorter the time required to reach the drying equilibrium.Elm wood with different initial moisture contents and particle sizes could be dried within 27 min.When the drying temperature increased from 160℃to 220℃,CO2 emissions increased from 0.000 4 Nm3/kg to 0.004 3 Nm3/kg.VOCs could not be detected when the drying temperatures were lower than 180℃.At a drying temperature of 200℃,VOCs emissions reached 2.4 g/kg,primarily consisted of aldehydes and ketones,with furfural accounted for 67.5%of the total.Compared with other kinetic models,the Page model could accurately describe the hot air drying process of elm wood(dry basis moisture content of 45%)with an effective moisture diffusivity ranged from 2.46×10-8 to 9.77×10-8 m2/s,a drying activation energy of 33.429 kJ/mol.The length of rotary dryer designed for processing capacity of 10 t/h biomass had a drum of 10.4 m,an inner diameter of 2.6 m,a drum rotation speed between 21.77 to 26.22 r/min,and a thermal load of 100 828 kJ/h for drying 10 t/h biomass.