Low pollution method of burning fuels

Patent · Tue Mar 06 04:00:00 EST 1984

OSTI ID:6649292

Moss, G

A low pollution method of burning a fuel comprises gasifying the fuel in a gasifier bed containing particles which are fluidized by a fluidizing gas containing substantially no inert components. The resulting combustible gas is burned with air diluted with nitrogen to reduce NO /SUB x/ formation. In addition, NO /SUB x/ production from the nitrogen content of the fuel is reduced as a result of the gasification of the fuel to combustible gas before combustion with air. Preferably the gasifier bed contains CaO to fix sulfur from the fuel as CaS. In one embodiment, the gasifier bed (51) contains CaSO/sub 4/ and the fluidizing gas contains H/sub 2/, inter alia, which mediates the transfer to the fuel of chemically-bound oxygen from the CaSO/sub 4/ (which is thereby reduced to CaS). Particles containing CaS are passed to an oxidizer bed (72) wherein they are fluidized by air. The CaS is exothermically oxidized to CaSO/sub 4/ by extracting oxygen from the air which is thereby heated and substantially exhausted of oxygen. The hot CaSO/sub 4/ is transferred from the oxidizer bed (72) to the gasifier bed (51) for gasifying further amounts of fuel, and the hot oxygen-depleted air is cooled by heat exchange (in 80) with boiler feed water, and then added to combustion air (in 69) to reduce the peak flame temperature when the combustible gas is burned at the burner (56) thereby mitigating NO /SUB x/ production from reactions in the flame between oxygen and nitrogen from the atmosphere.

• Assignee: Exxon Research and Engineering Co.
• Patent Number(s): US 4435148
• OSTI ID: 6649292
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010404 -- Coal
Lignite
& Peat-- Gasification
014000* -- Coal
Lignite
& Peat-- Combustion
AIR POLLUTION ABATEMENT
ALKALINE EARTH METAL COMPOUNDS
BOILERS
BURNERS
CALCIUM COMPOUNDS
CALCIUM OXIDES
CALCIUM SULFATES
CALCIUM SULFIDES
CARBONACEOUS MATERIALS
CHALCOGENIDES
CHEMICAL REACTIONS
COAL
COAL GASIFICATION
COMBUSTION
CONTROL
DESIGN
ELEMENTS
ENERGY SOURCES
FLUIDIZED BED
FLUIDS
FOSSIL FUELS
FUEL GAS
FUEL OILS
FUEL-AIR RATIO
FUELS
GAS FUELS
GASES
GASIFICATION
LIQUID FUELS
MATERIALS
NITROGEN COMPOUNDS
NITROGEN OXIDES
NONMETALS
OILS
ORGANIC COMPOUNDS
OTHER ORGANIC COMPOUNDS
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PETROLEUM PRODUCTS
POLLUTION ABATEMENT
RETENTION
SULFATES
SULFIDES
SULFUR
SULFUR COMPOUNDS
SULFUR CONTENT
TEMPERATURE CONTROL
THERMOCHEMICAL PROCESSES