Process and apparatus for the drying material of coal of poor quality, the process to remove a substantial portion of impurities of coal of poor quality, apparatus for drying.As well as low quality coal and peat, subjected to a drying process

摘要

Inventor: GreeneDocket No.: 5366-FPAAbstract Of The DisclosureA process and apparatus is disclosed for removing asubstantial portion of water and impurities from low rank coaland peat, whereby an improved coal or peat product (not found innature) is obtained. The low rank coal and peat are subjected toa superheated gaseous medium, thereby substantially desorbing themoisture from the coal or peat and producing superheated gases.A substantial portion of the superheated gases produced arerecycled back in contact with the coal being dried. Sufficientheat is added to the recycled gases, in response to monitoring,so that the recycled gases are maintained in a substantiallysuperheated condition throughout. This process produces a dried,substantially purified product which retains a substantialportion of its volatile content, which has an improved heat valueper unit weight, and which will not absorb substantial moisturewhen stored or transported. In one embodiment, the processutilizes superheated steam to initiate the drying process. Inanother embodiment, that minor portion of the superheated gasesin excess of the original volume not being recycled arerecovered, and the fuel content thereof is used to provide energyfor reheating the gases being recycled. In yet anotherembodiment, the processes are maintained at low pressures ofunder approximately 50 inches water column pressure. The processand apparatus provided also removes a substantial portion of theimpurities such as sulfur, from the low rank coals and peat. Thedried product may be cooled, and the impurities may be separatedtherefrom.