INTRODUCTION

The drying process of raw material in sawdust dryer machine is mainly realized by two processes. One is the heat transfer process: heat in drying medium is transferred into raw material to make the water inside become steam. The other is the diffusion process: evaporated steam diffuses to drying medium. Faster the above two processes, quicker the drying speed. Thus when referring to the factors for influencing the drying speed, we need to think about from the speeds of heat transfer and diffusion.

Higher the temperature of drying medium, faster the speed of drying process. Large difference in temperature between drying medium and raw material results the high speed of heat transfer. If drying raw material directly with high-temperature flue gas, better effect will be acquired. Thus, if necessary, we should use the flue gas as often as possible. Lower the relative humidity of drying medium, faster the gasification of water content and drying speed. If we use the flue gas as drying medium, its humidity is related with the air humidity, water and hydrogen content in fuel.

Bigger the contact surface between drying medium and raw material, faster the drying speed. Thus during the drying process, we can break raw material into pieces or make raw material in suspension state. Also, we can install the lifting board or grating in the sawdust rotary dryer so as to widen the contact area between drying medium and raw material, improve the drying speed and shorten drying time.

During the actual working process of sawdust rotary dryer, if the drying speed is slow, the total output will decrease a lot. The point to improve the drying efficiency and output of sawdust drying machine has been focused all the time. Thus the above points are very helpful. Dingli Heavy Machinery: http://www.ft-dryer.com.