Method for removing sulfur dioxide from exhaust gas

Patent · Tue Oct 19 04:00:00 EDT 1976

OSTI ID:7228453

Saitoh, S; Kodama, K; Miyamori, T; Watanabe, T; Konno, K; Yaguchi, K

A sulfur dioxide-containing exhaust gas is scrubbed by contact with an aqueous solution containing an alkali salt of an organic acid to dissolve sulfur dioxide in the aqueous solution in the form of alkali sulfite. The alkali sulfite in the solution is converted by oxidation into alkali sulfate, which is contacted for reaction with a calcium compound to form calcium sulfate. The calcium sulfate so formed is separated by filtration from the aqueous solution for recovery while the filtrate is recycled for use as the aqueous solution for scrubbing the exhaust gas. The concentration of alkali sulfite in the scrubbing aqueous solution is maintained at a level of less than 1% to ensure efficient removal of sulfur dioxide from the exhaust gas in the form of calcium sulfate. 5 claims, 1 drawing figure.

• Assignee: Kureha Kagaku Kogyo Kabushiki Kaisha
• Patent Number(s): US 3987149
• OSTI ID: 7228453
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010800* -- Coal
Lignite
& Peat-- Waste Management
500200 -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
ALKALINE EARTH METAL COMPOUNDS
AQUEOUS SOLUTIONS
CALCIUM COMPOUNDS
CALCIUM SULFATES
CHALCOGENIDES
CHEMICAL REACTIONS
DESULFURIZATION
DISPERSIONS
EXHAUST GASES
FILTRATION
GASEOUS WASTES
MIXTURES
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
REMOVAL
SEPARATION PROCESSES
SOLUTIONS
SULFATES
SULFUR COMPOUNDS
SULFUR DIOXIDE
SULFUR OXIDES
WASTES