Method of extracting coal from a coal refuse pile

Patent · Tue Jan 01 00:00:00 EST 1991

OSTI ID:867922

Yavorsky, Paul M ^[1]

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1. Monongahela, PA

A method of extracting coal from a coal refuse pile comprises soaking the coal refuse pile with an aqueous alkali solution and distributing an oxygen-containing gas throughout the coal refuse pile for a time period sufficient to effect oxidation of coal contained in the coal refuse pile. The method further comprises leaching the coal refuse pile with an aqueous alkali solution to solubilize and extract the oxidized coal as alkali salts of humic acids and collecting the resulting solution containing the alkali salts of humic acids. Calcium hydroxide may be added to the solution of alkali salts of humic acid to form precipitated humates useable as a low-ash, low-sulfur solid fuel.

• Research Organization: National Energy Technology Laboratory (NETL), Pittsburgh, PA, Morgantown, WV (United States)
• Assignee: United States of America as represented by Secretary of (Washington, DC)
• Patent Number(s): US 5035722
• OSTI ID: 867922
• Country of Publication: United States
• Language: English

Related Subjects

method
extracting
coal
refuse
pile
comprises
soaking
aqueous
alkali
solution
distributing
oxygen-containing
gas
throughout
time
period
sufficient
effect
oxidation
contained
leaching
solubilize
extract
oxidized
salts
humic
acids
collecting
resulting
containing
calcium
hydroxide
added
acid
form
precipitated
humates
useable
low-ash
low-sulfur
solid
fuel
refuse pile
coal refuse
aqueous alkali
resulting solution
alkali salts
humic acid
solid fuel
period sufficient
oxygen-containing gas
solution containing
time period
containing gas
calcium hydroxide
alkali solution
comprises leaching
extracting coal
alkali salt
/44/