Centrifuge dewatering and reconstitution of fine coal: A pilot-plant application of the GranuFlow Process

A continuous pilot-scale test of the GranuFlow Process was conducted using a screen-bowl centrifuge for the dewatering and reconstitution of column-fl otation concentrate at a coal preparation plant in Virginia. In this test, a slipstream of the fine clean-coal slurry from the column flotation concen trate was treated with a bitumen emulsion before dewatering. The treated pr oducts from the screen-bowl centrifuge appeared to be dry and in a free-flo wing granular form, while the untreated products were wet, sticky and diffi cult to handle. Test results indicated that the average moisture contents o f the dewatered coal products were 35.7%, 35.5%, 32.6%, 29.9% and 26.5% (by weight) with Orimulsion additions of 0.0%, 0.7%, 3.2%, 4.8% and 6.4% (by w eight), respectively. The handleability and dust reduction of the dewatered coal products were also vastly improved.