Correlation of physical coal separations: Part I

Technical Report · Sat Sep 01 00:00:00 EDT 1979

DOI:https://doi.org/10.2172/5888751· OSTI ID:5888751

Hise, E. C.

Experimental separations of the inorganic material from a coal by the specific-gravity (wet), high-gradient magnetic (dry), and open-gradient magnetic (dry) processes were performed and analyzed to compare for Btu recovery vs efficiency of removal of pyrite and ash and to determine the degree of liberation of the inorganics by the crushing. It is shown that the liberated minerals can be separated from dry crushed coal by both the high-gradient magnetic separation (HGMS) and the open-gradient magnetic separation (OGMS) processes with an efficiency comparable to the specific-gravity (float-sink) process. Coal feed through the HGMS was by gravity with low-velocity transport air and through the OGMS by vibrating tray and by gravity free fall. The degree of liberation of the minerals was assayed by a set of specific-gravity separations. These separations were performed with size fractions in the range of -14 +100 mesh of Western Kentucky seam No. 9 coal in the laboratories of the Bureau of Mines (specific gravity), the Oak Ridge National Laboratory (ORNL) (open-gradient magnetic and specific gravity), and of a magnetic separator manufacturer (high-gradient magnetic). Several magnetic processes have been shown to separate efficiently the liberated minerals from dry crushed coal. The high-gradient magnetic separator can attract and retain the paramagnetic particles on the magnetized mesh. Production-scale machines suited for HGMS of dry crushed coal are commercially available. The open-gradient magnetic separator can deflect both the diamagnetic and the paramagnetic particles in a freely falling stream of coal into a spectrum that can be split to separate the minerals from the clean coal. The process, as demonstrated on a laboratory scale, appears to be simple and efficient and, therefore, merits further development.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 5888751
• Report Number(s): ORNL-5570
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
COAL
PURIFICATION
COAL PREPARATION
MAGNETIC SEPARATORS
ASHES
COMPARATIVE EVALUATIONS
PYRITE
REMOVAL
SEPARATION PROCESSES
CARBONACEOUS MATERIALS
CHALCOGENIDES
COMMINUTION
CONCENTRATORS
ENERGY SOURCES
FOSSIL FUELS
FUELS
IRON COMPOUNDS
IRON SULFIDES
MINERALS
ORES
PYRITES
RESIDUES
SULFIDES
SULFUR COMPOUNDS
SULFUR ORES
TRANSITION ELEMENT COMPOUNDS
013000* - Coal
Lignite
& Peat- Transport
Handling
& Storage
010402 - Coal
Lignite
& Peat- Purification & Upgrading