Method for increased mine recovery and upgrading of lignite

Patent · Tue Oct 28 00:00:00 EST 1986

OSTI ID:6964291

Jones, E E; Pearce, T A; Laird, III, D C; Everitt, J H

A process is described for upgrading lignite ores to remove a substantial proportion of the non-combustible ash content associated with the lignite which comprises: (1) sizing by crushing to a maximum top size of less than about 6 inches in two directions (axis's) (2) separating the clay and/or rock (gangue) which are discarded and lignite from each other in a float-sink gravity separator, (3) directing the float containing the lignite and some small particles of clay to a screen deck to size the float into at least three portions, (4) washing the first two screen proportions to free them of clays, (5) collecting the third portion consisting of fines and water as an underflow from the deck, (6) treating the underflow in a hydrocyclone to recover a substantial quantity of the lignite associated with some clays as the overflow and an aqueous stream containing the remainder of the clays and some lignite as the underflow and discarding. (7) treating overflow to effectuate a size separation of the lignite substantially free of clays as underflow and the clays with some fine lignites as the overflow. (8) seive bend dewatering and washing and drying the underflow and combining the resultant product with the +28 mesh lignite product, (9) flocculating (clarifier-thickener) the refuse from the seive bend and the overflow from (7) to about 35% solids, (10) further concentrating the refuse, as by filtration, to a discardable solid.

• Assignee: Dow Chemical Co., Midland, MI
• Patent Number(s): US 4619669
• OSTI ID: 6964291
• Resource Relation: Patent File Date: Filed date 23 Nov 1984
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
LIGNITE
CRUSHING
DEASHING
WASHING
AQUEOUS SOLUTIONS
ASH CONTENT
CLAYS
COAL MINING
COAL PREPARATION
CYCLONE SEPARATORS
DRYING
FILTRATION
FLOCCULATION
PARTICLE SIZE
SCREENS
SIZING
WATER REMOVAL
BROWN COAL
CARBONACEOUS MATERIALS
CLEANING
COAL
COMMINUTION
CONCENTRATORS
DISPERSIONS
ENERGY SOURCES
EQUIPMENT
FOSSIL FUELS
FUELS
INERTIAL SEPARATORS
MATERIALS
MINING
MIXTURES
POLLUTION CONTROL EQUIPMENT
PRECIPITATION
REMOVAL
SEPARATION EQUIPMENT
SEPARATION PROCESSES
SIZE
SOLUTIONS
010300* - Coal
Lignite
& Peat- Preparation- (1987-)