Removal of SO/sub 2/ and NO/sub x/ from stack gas by reaction with calcium hydroxide solids

Conference · Thu Jan 01 00:00:00 EST 1987

OSTI ID:6264694

Chu, P; Rochelle, G T

Previous workers have shown that simultaneous SO/sub 2//NO/sub x/ removal can be obtained in a dry scrubbing system with Ca(OH)/sub 2/ promoted by an additive such as NaOH, and that fly ash and product recycle improve the reactivity of the solids toward SO/sub 2/. To test SO/sub 2//NO/sub x/ removal with fly ash and product recycle, bench-scale experiments with a packed bed reactor were performed at bag filter conditions. The most reactive solid for NO/sub x/ removal was prepared by slurrying Ca(OH)/sub 2/ with fly ash, CaSO/sub 3/, and NaOH. The best conditions for NO/sub x/ removal were the highest temperature (125/sup 0/C) and greatest concentrations of SO/sub 2/ (1500 ppm) and O/sub 2/ (20%). At the best conditions, NO/sub x/ removed in 1 hour was 3 - 4 moles per 100 moles Ca(OH)/sub 2/, compared to 5 - 10 moles SO/sub 2/ removed per 100 moles Ca(OH)/sub 2/. The best SO/sub 2/ removal was obtained at the highest relative humidities/lowest temperatures (55% RH/65/sup 0/C) with solids prepared by slurrying Ca(OH)/sub 2/ with flyash and NaOH. At these conditions, SO/sub 2/ removed in 1 hour was 60 - 80 moles per 100 moles Ca(OH)/sub 2/, compared to 0.5 to 1 moles NO/sub x/ removed per 100 moles Ca(OH)/sub 2/.

• OSTI ID: 6264694
• Report Number(s): CONF-870323-
• Resource Relation: Conference: American Institute of Chemical Engineers spring national meeting, Houston, TX, USA, 29 Mar 1987; Other Information: Technical Paper 78E
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
02 PETROLEUM
20 FOSSIL-FUELED POWER PLANTS
54 ENVIRONMENTAL SCIENCES
ADSORBENTS
COMPARATIVE EVALUATIONS
TEMPERATURE EFFECTS
CALCIUM HYDROXIDES
CHEMICAL REACTION KINETICS
DRY SCRUBBERS
ADDITIVES
FLUE GAS
DESULFURIZATION
NITROGEN OXIDES
REMOVAL
SODIUM HYDROXIDES
SULFUR DIOXIDE
AIR POLLUTION CONTROL
CALCIUM SULFATES
FLY ASH
SORPTIVE PROPERTIES
AEROSOL WASTES
ALKALI METAL COMPOUNDS
ALKALINE EARTH METAL COMPOUNDS
ASHES
CALCIUM COMPOUNDS
CHALCOGENIDES
CHEMICAL REACTIONS
CONTROL
EQUIPMENT
GASEOUS WASTES
HYDROGEN COMPOUNDS
HYDROXIDES
KINETICS
NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
POLLUTION CONTROL
POLLUTION CONTROL EQUIPMENT
REACTION KINETICS
RESIDUES
SCRUBBERS
SODIUM COMPOUNDS
SULFATES
SULFUR COMPOUNDS
SULFUR OXIDES
SURFACE PROPERTIES
WASTES
010800* - Coal
Lignite
& Peat- Waste Management
020800 - Petroleum- Waste Management
200202 - Fossil-Fueled Power Plants- Waste Management- Noxious Gas & Particulate Emissions
500200 - Environment
Atmospheric- Chemicals Monitoring & Transport- (-1989)