Magnetite-coal separation by continuous HGMS

Journal Article · Mon Nov 01 04:00:00 EST 1982 · IEEE Trans. Magn.; (United States)

DOI:https://doi.org/10.1109/TMAG.1982.1062012· OSTI ID:5816067

Dobby, G S; Kelland, D R

Magnetite, slurried in water, is used to create an apparent heavy medium in which fine coal (0.1 to 2.4 mm) is cleaned of its mineral impurities. The magnetite is much finer in size (1 to 44 ..mu..m) than the coal and is usually recovered from the coal and refuse by magnetic drum separators. Their performance suffers from changes in feed conditions and a number of them are needed for the average coal cleaning plant. The authors have adapted HGMS for magnetite recovery because of its insensitivity to coal/magnetite ratio and slurry density and its ability to capture fine magnetite at high velocity. An open vertical matrix able to capture 10 ..mu..m (avg. size) magnetite without entraining 2 mm coal has been incorporated in a 1.85 m diameter continuous separator. Three-quarter ton samples of magnetite (in 1000 gallons of water) have been recovered with the matrix ring turning at 40 cm/s through a field of 6 kOe. A laminated core demagnetizing coil followed by water sprays removes the recovered magnetite. In preparation for this continuous program, tests of slurry densities from 20 to 35% solids and coal/magnetite ratios from 3:1 to 1:4 showed almost no variation in recovery or entrainment. A 4.8 m diameter separator, the largest currently available, with multiple heads, should be able to treat 350 tons of magnetite and coal per hour.

• Research Organization: MIT Francis Bitter National Magnet Laboratory, Cambridge, MA 02139
• OSTI ID: 5816067
• Journal Information: IEEE Trans. Magn.; (United States), Journal Name: IEEE Trans. Magn.; (United States) Vol. 18:6; ISSN IEMGA
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010402* -- Coal
Lignite
& Peat-- Purification & Upgrading
CARBONACEOUS MATERIALS
CHALCOGENIDES
COAL
COAL PREPARATION
CONCENTRATORS
DEMINERALIZATION
DISPERSIONS
ENERGY SOURCES
ENTRAINMENT
FOSSIL FUELS
FUELS
IRON COMPOUNDS
IRON ORES
IRON OXIDES
MAGNETIC SEPARATORS
MAGNETITE
MATERIALS
MINERALS
MIXTURES
ORES
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PARTICLE SIZE
RECOVERY
SEPARATION PROCESSES
SIZE
SLURRIES
SUSPENSIONS
TRANSITION ELEMENT COMPOUNDS