Claims
- 1. A two stage process for hydroprocessing a hydrotreated distillate feedstock which process consisting essentially of:a) reacting said hydrotreated distillate feedstock in a first reaction stage in the presence of a once-through hydrogen-containing treat gas cascaded from the second reaction stage herein, said first reaction stage containing one or more reaction zones operated at hydrodesulfurization conditions wherein each reaction zone contains a bed of hydrotreating catalyst, and wherein said once-through hydrogen-containing treat gas cascaded from the second reaction stage comprises all of the vapor effluent from the second reaction stage; b) passing the resulting reactant to a separation zone wherein a vapor phase stream and a liquid phase stream are produced; c) collecting said vapor phase stream overhead; d) introducing fresh hydrogen-containing treat gas into a second reaction stage; and e) passing said liquid phase stream to a said second reaction stage in the presence of said fresh hydrogen-containing treat gas from step (d), said second reaction stage containing one or more reaction zones operated at aromatics saturation conditions wherein each reaction zone contains a bed of aromatics saturation catalyst, and wherein said hydrogen-containing treat gas is passed through said reaction stage countercurrent to the flow of said liquid phase stream.
- 2. The process of claim 1 wherein the liquid phase stream, before it passes through said second reaction stage is stripped to reduce its content of dissolved vapor phase product by contacting the liquid with a stripping gas.
- 3. The process of claim 2 wherein the stripping gas is the vapor phase effluent from the second reaction stage.
- 4. The process of claim 3 wherein the stripping gas and liquid phase stream is contacted in a vapor/liquid contacting zone which is vertically disposed above the second reaction zone.
- 5. The process of claim 4 wherein the vapor/liquid contacting zone is operated in countercurrent flow wherein vapor flows counter to the downward flowing liquid phase stream.
- 6. The process of claim 1 wherein the vapor phase stream from the first reaction stage is cooled and the resulting condensed liquid stream is separated from the remaining uncondensed stream, and a portion of the condensed liquid stream is combined with the liquid feed to the first reaction stage.
- 7. The process of claim 2 wherein the vapor phase steam from the fist reaction stage is cooled and the resulting condensed liquid stream is separated from the remaining uncondensed stream, and a portion of the condensed liquid stream is combined with the liquid feed to the second reaction stage.
- 8. The process of claim 4 wherein the vapor phase stream from the first reaction stage is cooled and the resulting condensed liquid stream is separated from the remaining uncondensed stream, and a portion of the condensed liquid stream is used as a quench liquid between two or more of the reaction zones of the first or second reaction stage.
- 9. The process of claim 4 wherein the first reaction stage is vertically disposed above the vapor/liquid contacting zone.
- 10. The process of claim 9 wherein the liquid feedstock flows downward through said one or more reaction zones countercurrent to said hydrogen-containing treat gas.
- 11. The process of claim 1 wherein the hydrogen-containing treat gas is cascaded from a vapor/liquid contacting zone which is vertically disposed above the second reaction zone.
Parent Case Info
This application claims the benefit of Provisional application Ser. No. 60/111,346, filed Dec. 8, 1998.
US Referenced Citations (73)
Foreign Referenced Citations (1)
Number |
Date |
Country |
1323257 |
Jul 1973 |
GB |
Provisional Applications (1)
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Number |
Date |
Country |
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60/111346 |
Dec 1998 |
US |