Advanced development of fine coal desulfurization and recovery technology. Quarterly technical progress report, January 1, 1977--March 31, 1977

Technical Report · Wed Jun 01 04:00:00 EDT 1977

DOI:https://doi.org/10.2172/5172709· OSTI ID:5172709

Wheelock, T. D.; Fisher, R. W.

The improvement and technical development of several promising methods for desulfurizing and recovering fine coal was continued. These methods include froth flotation, selective oil agglomeration, pelletization, and a chemical desulfurization process which involves leaching fine coal with a hot dilute solution of sodium carbonate containing dissolved oxygen or air under pressure. Numerous laboratory experiments and measurements were conducted in the areas of froth flotation, selective oil agglomeration and chemical desulfurization. The results showed that when pyrites are leached with an alkaline solution containing dissolved oxygen, the sulfur is extracted in the form of soluble sulfates and the iron is converted to ferric oxide or hematite. It was also shown that the rate of conversion of pyritic sulfur to soluble sulfates depends on the oxygen partial pressure with the rate increasing as the partial pressure is raised. Results which could lead to major improvements in the froth flotation method of separating coal and pyrites included the successful demonstration of an oxidative chemical pretreatment process which would greatly reduce the floatability of pyrite particles without greatly affecting the floatability of coal. Also conditions were identified which would aid in the selection of suitable cationic and anionic flotation collectors for effecting a better separation of coal and pyrite. The discovery that it may be possible to utilize relatively inexpensive, heavy residual fuel oils instead of light distillates for the selective agglomeration of fine coal enhances the economic viability of this method of coal beneficiation.

• Research Organization: Ames Lab., Iowa (USA)
• DOE Contract Number: W-7405-ENG-82
• OSTI ID: 5172709
• Report Number(s): IS-4210
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010402* -- Coal
Lignite
& Peat-- Purification & Upgrading
AGGLOMERATION
ALKALI METAL COMPOUNDS
CARBON COMPOUNDS
CARBONACEOUS MATERIALS
CARBONATES
CHALCOGENIDES
CHEMICAL REACTIONS
COAL
COAL FINES
COAL PREPARATION
DESULFURIZATION
DISSOLUTION
ENERGY SOURCES
FABRICATION
FLOTATION
FOSSIL FUELS
FUELS
IRON COMPOUNDS
IRON SULFIDES
LEACHING
MINERALS
MOLDING
OXYGEN COMPOUNDS
PELLETIZING
PYRITE
PYRITES
RECOVERY
REMOVAL
SEPARATION PROCESSES
SODIUM CARBONATES
SODIUM COMPOUNDS
SULFIDES
SULFUR COMPOUNDS
TRANSITION ELEMENT COMPOUNDS