Effects of ion-exchangeable cations on coal ash mineralogy

Conference · Thu Nov 01 04:00:00 EST 1984

OSTI ID:6232125

Falcone, S K; Hurley, J P; Schobert, H H

The purpose of this study was to investigate the effect of ion-exchangeable cations on ash mineralogies of two coals having different sodium contents. In addition, ashes of the same coals from which the exchangeable cations were removed were compared with ashes of the non-exchanged coals to determine the effect of removing alkali cations on ash mineralogies. Two lignites from the Gascoyne Mine, North Dakota, were chosen for this study. Both samples were collected within the same coal seam but from different pits: the Gascoyne Red and Blue Pits. Based on pilot plant combustion experience, the Gascoyne Red Pit coal is characterized as a low-fouling lignite relatively low in sodium, while the Gascoyne Blue Pit coal is a moderate to high-fouling lignite relatively high in sodium. Ion-exchange data for these two coals has been previously reported. Results suggest that systems abundant in calcium and sodium cations form feldspathoids at lower temperatures than systems deficient in these cations by mechanisms previously described. At 1000/sup 0/C, both calcium and sodium were present in the form of gehlenite and nepheline, respectively. In no case did mutual substitution of calcium and sodium occur within the same aluminosilicate structure. Perhaps this behavior reflects a preference for specific cations to substitute within aluminosilicate structures having different coordination configurations. 6 references, 2 tables.

• Research Organization: North Dakota Univ., Grand Forks (USA). Energy Research Center
• DOE Contract Number: FC21-83FE60181
• OSTI ID: 6232125
• Report Number(s): DOE/FE/60181-107; CONF-850357-1; ON: DE85002308
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010600* -- Coal
Lignite
& Peat-- Properties & Composition
ALKALI METAL COMPOUNDS
ALKALINE EARTH METAL COMPOUNDS
ASHES
BROWN COAL
CALCIUM COMPOUNDS
CARBONACEOUS MATERIALS
CHEMICAL COMPOSITION
COAL
ENERGY SOURCES
FOSSIL FUELS
FUELS
ION EXCHANGE
LIGNITE
MATERIALS
MINERALOGY
RESIDUES
SODIUM COMPOUNDS
TEMPERATURE DEPENDENCE