Process for the combined removal of SO/sub 2/ and NO/sub x/ from flue gas
A process of the simultaneous removal of NO/sub x/ and SO/sub 2/ from a fluid stream itself comprised of NO/sub x/ and SO/sub x/, is described which comprises: (A) contacting the fluid stream in a contacting zone with an aqueous reaction mixture itself comprising an effective amount of an iron (II) chelate of an amino acid moiety having at least one -SH group selected from amino acids, N-substituted amino acids, natural peptides and synthetic peptides, and an alkali which comprises a basic salt selected from the salts of sodium, potassium, lithium, calcium or magnesium, (B) separating the fluid stream from the particulates formed in step (A) which particulates comprise the chelate of the amino acid moiety and fly ash; (C) washing with the particulates of step (B) with a relatively neutral aqueous solution having a pH of between about 5 and 8 with subsequent separation of the aqueous wash and the particulates; (D) subsequently washing the particulates of step (C) with an acidic aqueous solution of a mineral acid; (E) washing of the particulates of step (D) with an alkaline aqueous solution having a pH of between about 9 and 12 with subsequent separation of the aqueous wash and the particulates; (F) adding additional amino acid moiety, iron (II) ion, and an alkali which comprise a basic salt selected from the salts of sodium potassium, lithium, calcium or magnesium to produce an effective concentration of chelating aqueous solution or slurry having a pH of between about 4 to 12; and (G) recycling the aqueous solution of step (F) to the contact zone of step (A).
- Assignee:
- Dept. of Energy, Washington, DC
- Patent Number(s):
- US 4732744
- OSTI ID:
- 5089151
- Country of Publication:
- United States
- Language:
- English
Similar Records
A process for the preparation of cysteine from cystine
A process for the preparation of cysteine from cystine
Related Subjects
010800* -- Coal
Lignite
& Peat-- Waste Management
20 FOSSIL-FUELED POWER PLANTS
200202 -- Fossil-Fueled Power Plants-- Waste Management-- Noxious Gas & Particulate Emissions
500200 -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
ACIDIFICATION
AIR POLLUTION CONTROL
ALKALI METAL COMPOUNDS
AMINO ACIDS
AQUEOUS SOLUTIONS
CARBOXYLIC ACIDS
CHALCOGENIDES
CHELATING AGENTS
CHEMICAL REACTIONS
CHLORIDES
CHLORINE COMPOUNDS
CLEANING
CONTROL
DENITRATION
DESULFURIZATION
DISPERSIONS
FLUE GAS
GASEOUS WASTES
HALIDES
HALOGEN COMPOUNDS
IRON COMPOUNDS
MIXTURES
NITROGEN COMPOUNDS
NITROGEN OXIDES
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PEPTIDES
POLLUTION CONTROL
PROTEINS
RECYCLING
REMOVAL
SOLUTIONS
SULFUR COMPOUNDS
SULFUR DIOXIDE
SULFUR OXIDES
TRANSITION ELEMENT COMPOUNDS
WASHING
WASTES