Heated fly ash/hydrated lime slurries for SO[sub 2] removal in spray dryer absorbers

Journal Article · Sun Jan 01 04:00:00 EST 1995 · Industrial and Engineering Chemistry Research; (United States)

DOI:https://doi.org/10.1021/ie00040a032· OSTI ID:6559485

Sanders, J F; Keener, T C; Wang, J ^[1]

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1. Univ. of Cincinnati, OH (United States). Dept. of Civil and Environmental Engineering

Coal fly ashes have been slurried with quicklime at elevated temperatures to determine their reactivity with SO[sub 2] in a minipilot spray dryer. Bench-scale experimental results indicate that this hydration process greatly increases the total surface area of the solids. Minipilot-scale spray dryer tests reveal that the slurry reaction step can significantly increase calcium utilization and SO[sub 2] removal of these fly ash/quicklime sorbents, depending on the type of fly ash used. One type of fly ash showed considerably better reactivity in the spray dryer tests. This enhancement is considered due to the presence of calcium silica hydrate material formed from the reaction between calcium and the alumina silicate found in the fly ashes and the difference in reactivity due to the type of calcium silica hydrate material formed. The benefit, however, decreases with the calcium feed rate. Pozzolanic strength tests were performed on the fly ashes used, and the measured unconfined compressive strengths followed the reactivity results in the spray dryer; the most reactive fly ash possessed the highest pozzolanic activity.

• OSTI ID: 6559485
• Journal Information: Industrial and Engineering Chemistry Research; (United States), Journal Name: Industrial and Engineering Chemistry Research; (United States) Vol. 34:1; ISSN IECRED; ISSN 0888-5885
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010800* -- Coal
Lignite
& Peat-- Waste Management
ACTIVATION ENERGY
ADSORBENTS
AEROSOL WASTES
ALKALINE EARTH METAL COMPOUNDS
ASHES
CALCIUM COMPOUNDS
CALCIUM OXIDES
CHALCOGENIDES
CHEMICAL REACTIONS
COMBUSTION PRODUCTS
COMPRESSION STRENGTH
DESULFURIZATION
DRY SCRUBBERS
DRYING
ENERGY
EQUIPMENT
FLUE GAS
FLY ASH
GASEOUS WASTES
MECHANICAL PROPERTIES
OXIDES
OXYGEN COMPOUNDS
POLLUTION CONTROL EQUIPMENT
REMOVAL
RESIDUES
SCRUBBERS
SORPTIVE PROPERTIES
SPRAY DRYING
SULFUR COMPOUNDS
SULFUR DIOXIDE
SULFUR OXIDES
SURFACE PROPERTIES
WASTES