Claims
- 1. A partial oxidation process for producing synthesis gas, reducing gas or fuel gas from a fuel feedstock comprising ashcontaining solid carbonaceous and/or liquid hydrocarbonaceous fuel comprising the steps of:
- (1) reacting said fuel feedstock by partial oxidation with a free-oxygen containing gas and a temperature moderator in a free-flow vertical refractory-lined gas generator at an autogenous temperature in the range of about 20.degree. F. to 200.degree. F. below the softening temperature of the ash in said fuel, a pressure in the range of about 17 to 100 atmospheres, an O/C atomic ratio in the range of about 0.6 to 1.4, and a weight ratio of H.sub.2 O to carbon in the fuel feedstock in the range of about 0.3 to 4.0, to produce a raw gas stream comprising synthesis gas, reducing gas, or fuel gas with entrained carbon-rich fly-ash;
- (2) separating said carbon-rich fly-ash from said raw gas stream;
- (3) reacting a fuel comprising from about 20 to 100 wt. % of said carbon-rich fly-ash and about 0 to 80 wt.% comprising a supplemental fuel comprising ash-containing solid carbonaceous and/or liquid hydrocarbonaceous fuel by partial oxidation with a free-oxygen containing gas and a temperature moderator in a free-flow vertical refractory-lined gas generator at an autogenous temperature in the range of at least about 100.degree. F. above the fluid temperature of the slag produced, a pressure in the range of about 1 to 16 atmospheres and at least 16 atmospheres below the pressure in the gas generator in (1), an O/C atomic ratio in the range of about 0.6 to 1.3, and a weight ratio of H.sub.2 O to fuel in the range of about 0.1 to 5.0, to produce a raw product gas stream comprising synthesis gas, reducing gas, or fuel gas with entrained molten slag and containing less carbon-rich particulate material than that which would be produced if said fuel is reacted by partial oxidation at substantially the same operating conditions as those in the gas generator in (3) except for a higher pressure which is in the range of about 17 to 100 atmospheres; and
- (4) cooling said raw gas stream from (3).
- 2. The process of claim 1 wherein said solid carbonaceous fuel (1) is introduced into the gas generator as an aqueous slurry having a solids content in the range of about 30-65 wt. %, or alternatively as crushed solid carbonaceous fuel entrained in a gaseous medium selected from the group consisting of steam, recycle portion of the product gas, CO.sub.2, N.sub.2, and mixtures thereof.
- 3. The process of claim 2 wherein said solid carbonaceous fuel has a particle size such that 100% passes through an ASTM E11-70 Sieve Designation Standard (SDS) 1.40 mm Alternative No. 14.
- 4. The process of claim 1 provided with the steps of quench cooling of the raw gas stream from (1) in a pool of quench water whereby said carbon-rich fly-ash is separated from the raw gas stream; separating said carbon-rich fly-ash from water in a settler or clarifier and mixing together the carbon-rich fly-ash with said supplemental fuel to provide a fuel for reacting in (3).
- 5. The process of claim 1 provided with the steps of cooling the raw gas stream from (1) by passing it through a radiant and/or convection gas cooler followed by scrubbing the gas stream with water; whereby, said carbon-rich fly-ash is separated from the raw gas stream; separating said carbon-rich fly ash from water in a settler or clarifier; and mixing together the carbon-rich fly-ash with said supplemental fuel to provide a fuel for reacting in (3).
- 6. The process of claim 1 wherein the partial oxidation reactions in (1) and (3) take place in the same or different gas generators.
- 7. The process of claim 1 wherein about 5.0 to 30.0 wt. % of carbon-rich fly-ash (basis weight of carbon in fuel feedstock) is produced in (1) and about 0.01 to 4.0 wt.% of carbon-rich fly-ash (basis weight of carbon in fuel fed to gas generator in (3)) is produced in (3).
- 8. The process of claim 1 wherein the fuel reacted in (3) is introduced into the gas generator as an aqueous slurry having a solids content in the range of about 30-65 wt. %, or alternatively as crushed fuel entrained in a gaseous medium selected from the group consisting of steam, recycle portion of the product gas, CO.sup.2, N.sub.2, and mixtures thereof.
- 9. The process of claim 1 provided with the step of introducing an additive into the gas generator in (1) to facilitate the removal of sulfur-containing gases and/or to raise the ash-fusion temperature of ash in the feed.
- 10. The process of claim 9 wherein from about 0.05 to 10 parts by weight of additive are introduced into the gas generator in (1) for each part by weight of ash in the fuel feedstock.
- 11. The process of claim 9 wherein said additive is selected from the group consisting of iron-containing material, copper-containing material, calcium-containing material, and mixtures thereof.
- 12. The process of claim 10 wherein said additives are introduced to remove sulfur.
- 13. The process of claim 9 wherein said additive is selected from the group consisting of aluminum-containing material, magnesium-containing material, titanium-containing material, silicon-containing material, and mixtures thereof.
- 14. The process of claim 13 wherein said additives are introduced to raise the ash-fusion temperature of the ash in the fuel feed.
- 15. The process of claim 1 wherein the fuel feedstock in (1) and the supplemental fuel in (3) is an ash-containing solid carbonaceous fuel selected from the group consisting of coal i.e. anthracite, bituminous, subbituminous, or lignite; coke from coal; petroleum coke; oil shale; tar sands; asphalt; pitch; and mixtures thereof.
- 16. The process of claim 1 wherein the fuel feedstock in (1) and the supplemental fuel in (3) is an ash-containing liquid hydrocarbonaceous fuel selected from the group consisting of virgin crude, residue from petroleum distillation and cracking, petroleum distillates, reduced crude, whole crude, coal tar, coal derived oil, shale oil, tar sand oil and mixtures thereof.
- 17. A partial oxidation process for producing synthesis gas, reducing gas or fuel gas from an ash-containing fuel feedstock comprising bituminous coal comprising the steps of:
- (1) reacting said fuel feedstock by partial oxidation with a free-oxygen containing gas and a temperature moderator in a free-flow vertical refractory-lined gas generator at an autogenous temperature in the range of about 20.degree. F. to 200.degree. F. below the softening temperature of the ash in said fuel, a pressure in the range of about 17 to 100 atmospheres, an O/C atomic ratio in the range of about 0.6 to 1.4, a weight ratio of H.sub.2 O to carbon in the fuel feedstock in the range of about 0.3 to 4.0, to produce a raw gas stream comprising synthesis gas, reducing gas, or fuel gas with entrained carbon-rich fly-ash;
- (2) separating said carbon-rich fly-ash from said raw gas stream;
- (3) reacting a fuel comprising from about 25 to 90 wt. % of said carbon-rich fly-ash and about 10 to 75 wt.% of bituminous coal by partial oxidation with a free-oxygen containing gas and a temperature moderator in a free-flow vertical refractory-lined gas generator at an autogenous temperature in the range of about 100.degree. F. above the fluid temperature of the slag produced, a pressure in the range of about 1 to 16 atmospheres and at least 16 atmospheres below the pressure in the gas generator in (1), an O/C atomic ratio in the range of about 0.6 to 1.3, and a weight ratio of H.sub.2 O to bituminous coal in the range of about 0.1 to 5.0, to produce a raw product gas stream comprising synthesis gas, reducing gas, or fuel gas with entrained molten slag and containing less carbon-rich particulate material than that which would be produced if said fuel is reacted by partial oxidation at substantially the same operating conditions as those in the gas generator in (3) except for a higher pressure which is in the range of about 17 to 100 atmospheres; and
- (4) cooling said raw gas stream from (3).
Parent Case Info
This is a continuation-in-part of application Ser. No. 07/397,945, filed Aug. 24, 1989.
US Referenced Citations (6)
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
397945 |
Aug 1989 |
|