Aqueous reaction of fly ash and Ca(OH)/sub 2/ to produce calcium silicate absorbent for flue gas desulfurization

Technical Report · Fri Jan 01 00:00:00 EST 1988

OSTI ID:5244825

Peterson, J; Rochelle, G T

To examine the effect of slurrying conditions upon solids reactivity, slurries of fly ash and Ca(OH)/sub 2/ were monitored for dissolved metal concentrations with atomic absorption spectrophotometry. The solids produced were dried and tested for reactivity towards SO/sub 2/ in a packed bed reactor at bag filter conditions. The solids formed in slurries containing 10 to 100 ppM of dissolved calcium were up to 40% more reactive than the solids formed in slurries containing less than 10 ppM or more than 100 ppM of dissolved calcium. The dissolved calcium concentration was affected by NaOH concentration, fly ash loading (g fly ashg Ca(OH)/sub 2/), slurry temperature, fly ash type, and the presence of CaSO/sub 3/ /center dot/ 0.5 H/sub 2/O. High calcium fly ash could be activated to remove 1.3 mmol SO/sub 2/g sorbent which is almost as reactive as the solids prepared by slurrying low calcium fly ash with Ca(OH)/sub 2/ at a fly ash loading of 4 (1.44 mmol SO/sub 2/g). Low and medium calcium fly ashes, under identical slurrying conditions removed only 0.33 mmol SO/sub 2/g sorbent.

• Research Organization: Texas Univ., Austin (USA). Dept. of Chemical Engineering
• DOE Contract Number: FG22-85PC81006
• OSTI ID: 5244825
• Report Number(s): DOE/PC/81006-T2; ON: DE88010129
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
54 ENVIRONMENTAL SCIENCES
20 FOSSIL-FUELED POWER PLANTS
CALCIUM SILICATES
SORPTIVE PROPERTIES
FLUE GAS
DESULFURIZATION
AQUEOUS SOLUTIONS
CALCIUM HYDROXIDES
FLY ASH
AEROSOL WASTES
ALKALINE EARTH METAL COMPOUNDS
ASHES
CALCIUM COMPOUNDS
CHEMICAL REACTIONS
DISPERSIONS
GASEOUS WASTES
HYDROGEN COMPOUNDS
HYDROXIDES
MIXTURES
OXYGEN COMPOUNDS
RESIDUES
SILICATES
SILICON COMPOUNDS
SOLUTIONS
SURFACE PROPERTIES
WASTES
010800* - Coal
Lignite
& Peat- Waste Management
500200 - Environment
Atmospheric- Chemicals Monitoring & Transport- (-1989)
200202 - Fossil-Fueled Power Plants- Waste Management- Noxious Gas & Particulate Emissions