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Characterization, extraction, and reuse of coal-gasification solid wastes. Volume 2. Leaching behavior of fixed-bed gasification ash derived from northern great plains lignite. Final report, May 1983-June 1986

Technical Report ·
OSTI ID:5993963

The leaching behavior of eight specimens of fixed-bed lignite-gasification ash, including ash from the Great Plains (GPGA) plant in Beulah, North Dakota, was studied. Four batch leaching tests were used: (1) EPA-EP; (2) a test with synthetic ND groundwater; (3) ASTM D3987-81; (4) long-term (120 day). One GPGA ash was leached according to the draft TCLP protocol. The EPA-EP test leachates from all of the ashes had metal concentrations a factor of ten or more below the values that define a hazardous waste according to the RCRA criteria. The ash specimens were highly alkaline and produced pH's in the range 10-13 during tests 2-4. Leachates from the EPA-EP test had RCRA metal concentrations comparable to, or less than, those derived from combustion ash derived from the same coal. The metal concentrations in leachates from tests 2 and 3 were also well below the RCRA limits. The long-term test used liquid-to-solid ratios of 2:1 and 20:1 and deionized water. During the 120 days, at least 5% of the Na, K, Al, S (as SO4), As, Mo, Se, B, and V in the ash was extracted.

Research Organization:
North Dakota Univ., Grand Forks (USA). North Dakota Mining and Mineral Resources Research Inst.
OSTI ID:
5993963
Report Number(s):
PB-87-230223/XAB
Country of Publication:
United States
Language:
English