Sulfur dioxide removal from gases using a modified lime

Patent · Tue Jan 21 04:00:00 EST 1992

OSTI ID:5381687

Lee, Y J; Benson, L B

This patent describes improvement in a process for removing sulfur dioxide from combustion gases by contacting the gases in a wet scrubbing unit with an aqueous scrubbing slurry, containing calcium components, for the removal of the sulfur dioxide, the calcium components provided in the slurry by adding aqueous slaked lime thereto, and a portion of the effluent from the scrubbing unit, containing calcium sulfite solids, is clarified to remove calcium sulfite solids therefrom as an aqueous sludge. The improvement comprises: the aqueous slaked lime added to the scrubbing slurry is formed by mixing lime and water, with the water containing a calcium sulfur-oxide salt in an amount sufficient to provide between about 0.3 to 5.0 percent by weight of the calcium sulfur-oxide salt based on the lime, whereby the average particle size of calcium sulfite solids in the aqueous sludge is increased to provide improved separation of water of the aqueous sludge therefrom.

• Assignee: Dravo Lime Co., Pittsburgh, PA (United States)
• Patent Number(s): A; US 5082639
• Application Number: PPN: US 7-610151
• OSTI ID: 5381687
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540120* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
AQUEOUS SOLUTIONS
CARBONATE ROCKS
CHALCOGENIDES
CHEMICAL REACTIONS
COMBUSTION
DISPERSIONS
FLUIDS
GASES
LIME-LIMESTONE WET SCRUBBING PROCESSES
LIMESTONE
MIXTURES
MODIFICATIONS
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PARTICLE SIZE
REMOVAL
ROCKS
SCRUBBING
SEDIMENTARY ROCKS
SIZE
SLUDGES
SLURRIES
SOLUTIONS
SULFUR COMPOUNDS
SULFUR DIOXIDE
SULFUR OXIDES
SUSPENSIONS
THERMOCHEMICAL PROCESSES