Bench scale development of the TRW process for cleaning coal (gravimelt process): Quarterly technical progress report for the period November 1984-January 1985

Technical Report · Fri Feb 01 04:00:00 EST 1985

OSTI ID:7162797

Major progress was made in defining and testing of the cocurrent leaching of coal with molten caustic. The purpose of this effort was to explore the possibility of simplifying the bench scale and proof of concept demonstration of the Gravimelt Process. While the countercurrent leaching of coal with molten caustic demonstrated ash and sulfur reductions far in excess of those required by the project scope of work, it has become apparent that implementation of countercurrent leaching at the 20 lb/h scale of this project would be more costly than the project budget would allow. This cost is due to the necessity of providing a filtration stage between each of the four reactor stages to reduce the caustic absorbed on the coal to no more than two weights per weight of coal. This is for efficient countercurrent movement of coal and caustic and to minimize regeneration requirements. Therefore, it was decided to test the potential of initially contacting the coal with only two weights of caustic and thus eliminating any need for filtration of molten caustic from coal. Thus, the product coal-caustic material leaving the cocurrent reactor contains approximately 1 to 2% dissolved sulfide and 2 to 4.5% dissolved ash upon treatment of the three project coals initially containing 3 to 4% sulfur and 5 to 10% ash and assuming 90% removal of sulfur and 95% removal of ash. These coal-derived products are then dissolved during the first stage of water washing of the coal, into a 50% aqueous caustic filtrate. They are then removed from the caustic by an aqueous regeneration route. The use of two weights of caustic per weight of coal was tested for all three project coals, Kentucky No. 11, Pittsburgh No. 8 and Bevier seams, and New Source Performance Standards were met in each case. 1 fig., 5 tabs.

• Research Organization: TRW Space and Technology Group, Redondo Beach, CA (USA)
• DOE Contract Number: AC22-83PC63032
• OSTI ID: 7162797
• Report Number(s): DOE/PC/63032-T13; ON: DE87003130
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010402* -- Coal
Lignite
& Peat-- Purification & Upgrading
ALKALI METAL COMPOUNDS
BENCH-SCALE EXPERIMENTS
CARBONACEOUS MATERIALS
CHEMICAL REACTIONS
COAL
COAL PREPARATION
COMPARATIVE EVALUATIONS
DATA
DEASHING
DESULFURIZATION
ENERGY SOURCES
EXPERIMENTAL DATA
FOSSIL FUELS
FUELS
GRAVIMELT PROCESS
HUMIC ACIDS
HYDROGEN COMPOUNDS
HYDROXIDES
INFORMATION
MATERIAL BALANCE
MATERIALS
MOLTEN SALTS
NUMERICAL DATA
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
REGENERATION
SALTS
SODIUM COMPOUNDS
SODIUM HYDROXIDES