Method of simultaneously removing sulfur dioxide and nitrogen oxides from exhaust gases

Patent · Tue Jan 29 04:00:00 EST 1980

OSTI ID:5586847

Kitamura, T; Takagi, H

A method is disclosed for simultaneously removing sulfur dioxide and nitrogen oxides from an exhaust gas which comprises the steps of: contacting the exhaust gas with an aqueous absorbing solution containing an iron chelate complex and an alkali metal sulfite to form alkali metal sulfur oxides comprising an alkali metal dithionate in the aqueous absorbing solution; separating the alkali metal sulfur oxides formed and accumulated from part or the whole of the aqueous absorbing solution by crystallization; and subjecting the alkali metal sulfur oxides separated together with a carbonaceous material to decomposition-reduction reaction at a temperature of at least about 700/sup 0/C to form an alkali metal sulfide and a gas comprising sulfur dioxide and carbon dioxide.

• Assignee: Asahi Kasei Kogyo K K (Japan)
• Patent Number(s): US 4186176
• OSTI ID: 5586847
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
424000* -- Engineering-- Pollution Control Equipment-- (1980-1989)
ABSORPTION
ALKALI METAL COMPOUNDS
AQUEOUS SOLUTIONS
CHELATES
CHEMICAL REACTIONS
COMBUSTION PRODUCTS
COMPLEXES
DECOMPOSITION
DENITRIFICATION
DESULFURIZATION
DISPERSIONS
EQUIPMENT
EXHAUST GASES
FLUIDS
GASEOUS WASTES
GASES
IRON COMPLEXES
MIXTURES
POLLUTION CONTROL EQUIPMENT
REDUCTION
SEPARATION PROCESSES
SOLUTIONS
SULFUR COMPOUNDS
TRANSITION ELEMENT COMPLEXES
WASTES