Patent ID: 8197561
Filing Date: 2012-06-12
Classification: C10L,F26B,Y02E

Abstract:
1. A multistage process for drying coal, comprising: (a) charging coal to a first fluidized bed reactor, charging air to said first fluidized bed reactor at a velocity of from about 5 to about 8 feet per second, subjecting said coal to a first temperature of from about 300 to about 550 degrees Fahrenheit, and removing from about 40 to about 60 weight percent of the water in said coal from said coal, wherein: i. said coal charged to said first fluidized bed reactor has a moisture content of from about 15 to about 40 percent and a combined oxygen content of from 10 to about 25 percent, ii. said first fluidized bed reactor is comprised of a fluidized bed with a fluidized bed density of from about 20 to about 50 pounds per cubic foot, whereby a first, partially dried coal is produced; (b) feeding said first, partially dried coal into a second fluidized bed reactor, feeding air into said second fluidized bed, subjecting said coal to a second temperature to about 250 degrees Fahrenheit, and removing water from said dried coal until no more than about 1 weight percent of water remains in said coal, (c) feeding said dried coal into a cooler where it is cooled to a temperature less than about 212 degrees Fahrenheit and mixed with water, said cooler employs at least one of a screw conveyor and a rotary tube.