Coal Dryer (Coal Rotary Dryer) is one of the common drying equipment for coal, which can dry various kinds of coal, such as brown coal,raw coal, coal slime, coal ash, coal cinder, coal slurry etc. The coal rotary dryer is widely used in power plant.
Working Principle of Coal Dryer
The coal fines are feed into the dryer and conveyed from the inlet to the discharge end by gravity due to a slight decline, and with shovel plates that line the inside of the drum. Hot gas is passed through the rotating drum in direct contact with the coal fines.The feed is tumbled up and over the shovel plates to maximize the agitation and contact with the hot gasses to induce drying. The dryer fill level is typically only 10% of the internal diameter. The low fill level aids in agitation of the product to insure direct contact with the hot gas. Due to the agitation and gas velocities, there is a substantial entrainment of particulate in the exhaust gas. The gas flow in the rotary dryer is typically co-current with the feed. The moisture and particulate have to be removed from the exhaust gas.