Production of sulfur from sulfur dioxide obtained from flue gas

Patent · Tue Jun 06 04:00:00 EDT 1989

OSTI ID:5462077

Miller, R

This patent describes a regenerable process for recovery of elemental sulfur from a gas containing sulfur dioxide comprising the steps of: contacting the gas with an aqueous, alkaline reaction medium containing sodium sulfite in concentration sufficient so that a slurry containing solid sodium sulfide is formed to react sulfur dioxide with sodium sulfite to form a solution containing dissolved sodium pyrosulfite and sodium sulfite; separating sulfur dioxide from the solution produced to leave a residual mixture containing water, sodium sulfite and a sodium pyrosulfite, the amount of sulfur dioxide separated being equal to about one-third the amount of sulfur dioxide which reacted with sodium sulfite; adding, in substantial absence of air, sufficient water and sodium bicarbonate to the residual mixture to react with the dissolved sodium pyrsulfide and form a slurry of solid sodium sulfite suspended in the resulting aqueous, alkaline reaction medium and gaseous carbon dioxide; separating the gaseous carbon dioxide; separating the solid sodium sulfite from the aqueous alkaline reaction medium and recycling the separated reaction medium; reducing the separated sodium sulfite to sodium sulfide; adding the sodium sulfide to an aqueous reaction medium containing sodium bicarbonate and, in the substantial absence of air, carbonating the resulting mixture with the gaseous carbon dioxide to form a slurry of solid particles of sodium bicarbonate dispersed in an aqueous reactor medium containing sodium bicarbonate, along with a gas composed primarily of hydrogen sulfide.

• Assignee: T-Thermal, Inc., Coshohocken, PA
• Patent Number(s): US 4837001
• OSTI ID: 5462077
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
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
AIR POLLUTION CONTROL
ALKALINE EARTH METAL COMPOUNDS
AQUEOUS SOLUTIONS
CHALCOGENIDES
CHEMICAL REACTIONS
CONTROL
DESULFURIZATION
DISPERSIONS
ELEMENTS
FLUE GAS
GASEOUS WASTES
MIXTURES
NONMETALS
OXIDES
OXYGEN COMPOUNDS
POLLUTION CONTROL
RECOVERY
SEPARATION PROCESSES
SOLUTIONS
SULFUR
SULFUR COMPOUNDS
SULFUR DIOXIDE
SULFUR OXIDES
WASTES