Design for sawdust drying machine

2020-05-12

The design of sawdust drying machine should be according to the features of sawdust:

*** It is inner water for the wet sawdust. It needs enough drying time so that the water inside sawdust can be evaporated into vapor and to be got rid of. The drying speed for different moisture content range is also different. For example, to reduce sawdust moisture content from 50% to 30% is much easier than from 30% to 15%.

*** It is light biomass material which's loose bulk density is less. In other words, for certain weight of sawdust, its volume is more. Thus the sawdust drying machine has to supply enough drying space so that the sawdust can be heated and dried sufficiently inside the dryers. It is also the reason that the size of sawdust dryer machine is some bigger.

In order to have good work performance of the sawdust drying machine, the design of sawdust dryer machine should pay attention as below:

*** According to the water quantity needed to be got rid of from wet sawdust, the burner and hot air furnace should can supply enough heat (hot flue gas). For the biomass material such as sawdust, usually to get rid of 1kg water from wet sawdust, it consume about 650 kcal heat.

*** The users should choose the most economical fuel such as waste wood, diesel, coal, natural gas, etc according to their actual situation.

*** The hot air system should be designed specially according to the type of fuel.

*** According to the processing quantity and water evaporation quantity, the induced draft fan should can supply enough air volume. Usually to take away 1000kg water vapor, it needs about 10000 m3 air volume.

*** The inner design of sawdust drying machine should can help to disperse the wet sawdust sufficiently, and so that there is more contact area between hot flue gas and sawdust, finally have good sawdust drying working performance.

The work flow of sawdust drying system usually is as follows:

Wet sawdust ---> Mechanical Feeding Hopper -->Belt Conveyor or screw conveyor ---> Inelt feeder ---> Sawdust dryer ---> Cyclone Separator ---> Outlet Feeder ---> Output belt conveyor or screw conveyor ---> Dried Sawdust.