Claims
- 1. A process for the liquefaction of sub-bituminous coal, comprising:
- contacting sub-bituminous coal with a liquefaction solvent in a first stage thermal liquefaction zone; hydrogenating first stage product in a second stage with a gaseous hydrogen, said second stage being operated at a temperature of no greater than 700.degree. F.; recovering from the second stage a first stream of 850.degree. F.- material, as net liquefaction product, and a second stream of a mixture of 850.degree. F.- material and 850.degree. F.+ material; recovering a pumpable stream of insoluble material in 850.degree. F.+ material from one of the first and second stage; and employing the pumpable stream and second stream for formulating liquefaction solvent for the first stage consisting essentially of from 5% to 10%, by weight, of insoluble material provided from one of the first and second stages, at least 45%, by weight, of 850.degree. F.- material provided from the second stage without further hydrogenation, 0% to 20%, by weight, of 850.degree. F.- material provided from the first stage without further hydrogenation, and the remainder of said liquefaction solvent being 850.degree. F.+ material, said 850.degree. F.+ material of the liquefaction solvent being provided in an amount of at least 20%, by weight, from the second stage without further hydrogenation and any remainder of the 850.degree. F.+ material of the liquefaction solvent being provided from the first stage without further hydrogenation.
- 2. The process of claim 1 wherein all of the 850.degree. F.+ material from the second stage is employed in formulating liquefaction solvent.
- 3. The process of claim 1 wherein the second stage temperature is at least 650.degree. F.
- 4. The process of claim 3 wherein the first stage temperature is from 800.degree. F. to 875.degree. F.
- 5. The process of claim 4 wherein there is essentially no gaseous hydrogen consumption in the first stage.
- 6. The process of claim 5 wherein the ratio of solvent to coal is from 1.2:1 to 3:1.
- 7. The process of claim 6 wherein insoluble material is separated from first stage product prior to hydrogenation in the second stage.
- 8. The process of claim 7 wherein the second stage hydrogenation is effected in an ebullated bed of catalyst.
- 9. The process of claim 1 wherein insoluble material is recovered from first stage product, prior to the second stage, as a pumpable stream in 850.degree. F.+ material, and said insoluble material for said liquefaction solvent is provided as a pumpable stream.
- 10. The process of claim 9 wherein all of the 850.degree. F.+ material employed in the liquefaction solvent, other than 850.degree. F.+ material included in the pumpable stream, is provided from the second stage.
- 11. The process of claim 10 wherein the second stage temperature is at least 650.degree. F.
- 12. The process of claim 1 wherein insoluble material is separated from second stage product as a pumpable stream in 850.degree. F.+ material, and insoluble material is provided for the liquefaction solvent as a pumpable stream.
- 13. The process of claim 12 wherein a portion of the recovered pumpable stream is employed for generating hydrogen.
- 14. A process for the liquefaction of sub-bituminous coal, comprising:
- contacting sub-bituminous coal with a liquefaction solvent in a first stage thermal liquefaction zone; separately recovering from the first stage liquefaction a pumpable stream of insoluble material in 850.degree. F.+ material, 850.degree. F.- material and a mixture of 850.degree. F.+ material and 850.degree. F.- material which is essentially free of insoluble material; hydrogenating said mixture in a second stage with gaseous hydrogen at a temperature of from 650.degree. F. to 700.degree. F.; recovering 850.degree. F.- material as net product from the second stage; recovering another mixture of 850.degree. F.- material and 850.degree. F.+ material from the second stage; and providing, without further hydrogenation, liquefaction solvent for the first stage consisting essentially of the pumpable stream, the 850.degree. F.- material from the first stage and said another mixture, said another mixture providing at least 45%, by weight, of 850.degree. F.- material for the liquefaction solvent, said 850.degree. F.- material from the first stage providing from 5% to 15%, by weight, of the 850.degree. F.- material of the liquefaction solvent, said pumpable stream providing from 5% to 10%, by weight, of insoluble material in the liquefaction solvent, and the remainder of the liquefaction solvent being 850.degree. F.+ material provided from the pumpable stream and the another mixture, with at least 20%, by weight, of the 850.degree. F.+ material in the liquefaction solvent being provided by the another mixture.
- 15. The process of claim 14 wherein said first stage is operated with essentially no gaseous hydrogen consumption.
- 16. The process of claim 15 wherein the first stage is operated at a temperature of 800.degree. F. to 875.degree. F.
- 17. The process of claim 15 wherein the second stage is effected in an ebullated bed of catalyst.
Government Interests
The Government of the U.S. of America has rights in this invention pursuant to Contract No. DEAC 22-82PC50021 awarded by the U.S. Department of Energy.
US Referenced Citations (13)