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US 11,168,274 B2Granted
Low sulfur coal additive for improved furnace operation
AssigneeADA-ES, Inc.
InventorsStephen Allen Johnson, John Wurster, John Philip Comer
Life of this patent
Estimating the term…
Abstract
The present invention is directed to additives for coal-fired furnaces, particularly furnaces using a layer of slag to capture coal particles for combustion. The additive(s) include iron, mineralizer(s), handling aid(s), flow aid(s), and/or abrasive material(s). The iron and mineralizers can lower the melting temperature of ash in low-iron, high alkali coals, leading to improved furnace performance.
Claims31
A method of preparing a solid fuel for combustion, comprising:
- contacting an iron-containing particulate additive comprising a plurality of particles with water to water-wet surfaces of the particles;
- drying the water-wetted surfaces of the particles to cohesively bond the water-wetted surfaces of the particles and form a plurality of cohesively bonded iron-containing particulates;
- and
- contacting coal with the plurality of cohesively bonded iron-containing particulates by one or more of mixing the plurality of cohesively bonded iron-containing particulates with the coal and adding the plurality of cohesively bonded iron-containing particulates to the coal.
1 more element
A method of preparing a solid fuel for combustion, comprising:
- contacting an iron-containing additive comprising a plurality of particles with water to water-wet surfaces of the particles;
- drying the water-wetted surfaces of the particles to cohesively bond the water-wetted surfaces of the particles and form a plurality of cohesively bonded iron-containing particulates;
- and
- mixing coal with the plurality of cohesively bonded iron-containing particulates,
- wherein the iron-containing additive comprises (i) at least about 50 wt % (dry basis) ferrous and ferric iron, wherein a ratio of ferric iron to ferrous iron in the iron-containing additive is less than about 2:1, and (ii) from about 0.5 to about 15 wt. % (dry basis) of a mineralizer.
2 more elements
A method of preparing a solid fuel for combustion, comprising:
- contacting an iron-containing additive comprising a plurality of particles with water to water-wet surfaces of the particles;
- drying the water-wetted surfaces of the particles to cohesively bond the water-wetted surfaces of the particles and form a plurality of cohesively bonded iron-containing particulates, wherein a cohesive layer is formed on the water-wetted surfaces of the particles;
- and
- adding the plurality of cohesively bonded iron-containing particulates to coal,
- wherein the iron-containing additive comprises (i) at least about 50 wt % (dry basis) ferrous and ferric iron, wherein a ratio of ferric iron to ferrous iron in the iron-containing additive is less than about 2:1, and (ii) a mineralizer, wherein the mineralizer reduces a temperature at which the iron-containing additive sinters.
2 more elements
A method of preparing a solid fuel for combustion, comprising:
- contacting an iron-containing additive comprising a plurality of particles with water to water-wet surfaces of the particles;
- drying the water-wetted surfaces of the particles to cohesively bond the water-wetted surfaces of the particles to one another and form a plurality of cohesively bonded iron-containing particulates;
- and
- contacting coal with the plurality of cohesively bonded iron-containing particulates,
- wherein the plurality of cohesively bonded iron-containing particulates comprises at least one of mill scale fines from steel production and dust from blast furnace gas cleaning equipment.
2 more elements
A method of preparing a solid fuel for combustion, comprising:
- contacting an iron-containing additive comprising a plurality of particles with water to water-wet surfaces of the particles;
- drying the water-wetted surfaces of the particles to cohesively bond the water-wetted surfaces of the particles to each other and form a plurality of cohesively bonded iron-containing particulates;
- and
- contacting coal with the plurality of cohesively bonded iron-containing particulates,
- wherein the iron-containing additive further comprises a mineralizer comprising at least one of calcium, magnesium, manganese fluorides, and sulfites and wherein the mineralizer reduces a temperature at which the iron-containing additive sinters.
2 more elements
Dependencies are inferred from the claim text.