Process for upgrading heavy oil using a reactor with a novel reactor separation system
Applicants have developed a new residuum full hydroconversion slurry reactor system that allows the catalyst, unconverted oil, hydrogen, and converted oil to circulate in a continuous mixture throughout an entire reactor with no confinement of the mixture. The mixture is separated internally, within one of more of the reactors, to separate only the converted oil and hydrogen into a vapor product while permitting the unconverted oil and the slurry catalyst to continue on into the next sequential reactor as a liquid product. A portion of the unconverted oil is then converted to lower boiling point hydrocarbons in the next reactor, once again creating a mixture of unconverted oil, hydrogen, converted oil, and slurry catalyst. Further hydroprocessing may occur in additional reactors, fully converting the oil. The oil may alternately be partially converted, leaving a concentrated catalyst in unconverted oil which can be recycled directly to the first reactor.
1. A process for the hydroconversion of heavy oils, said process comprising the following steps:
(a) providing at least two upflow reactors, a first reactor and a second reactor, with a separator located internally in at least one reactor;
(b) combining a heated heavy oil feed, an active slurry catalyst composition having particle sizes of 1-10 micron and a hydrogen-containing gas to form a mixture;
(c) passing the mixture of step (b) to the bottom of the first reactor, which is maintained at a temperature from 700 to 900 F and a pressure from 1500 to 3500 psia;
(d) separating internally in the first reactor a stream comprising reaction product, hydrogen gases, unconverted material and slurry catalyst into two streams, a vapor stream comprising reactor products and hydrogen, and a liquid stream comprising unconverted material and slurry catalyst;
(e) passing the vapor stream overhead to further processing, and passing the liquid stream, comprising unconverted material and slurry catalyst, from the first reactor as a bottoms stream;
(f) passing at least a portion of the liquid stream of step (e) to the bottom of the second reactor, which is maintained at hydroprocessing conditions, including elevated temperature and pressure;
(g) separating internally in the second reactor a stream comprising reaction product, hydrogen gases, unconverted material and slurry catalyst into two streams, a vapor stream comprising reactor products and hydrogen, and a liquid stream comprising unconverted material and slurry catalyst;
(h) passing the vapor stream overhead to further processing, and passing the liquid stream, comprising unconverted material and slurry catalyst, from the second reactor as a bottoms stream to further processing;
wherein the heavy oil is selected from the group consisting of atmospheric residuum, vacuum residuum, tar from a solvent deasphlating unit, oils derived from tar sands or bitumen, oils derived from coal, heavy crude oils, and oils derived from recycled oil wastes and polymers.
2. The process of claim 1 , wherein the liquid stream of step (h) is recycled to step (b), the mixture of step (b) further comprising recycled unconverted material and slurry catalyst.
3. The process of claim 1 , in which the upflow reactor is a recirculating reactor which employs a pump for recirculating of the slurry.
4. The process of claim 1 , in which the pressure is from 2000 through 3000 psia and the temperature is from 775 through 850 F.
5. The hydroconversion process of claim 1 , wherein the process is selected from the group consisting of hydrocracking, hydrotreating, hydrodesulphurization, hydrodenitrification, and hydrodemetalization.
6. The process of claim 1 , wherein the active slurry catalyst composition of claim 1 is prepared by the following steps:
(a) mixing a Group VIB metal oxide and aqueous ammonia to form a Group VIB metal compound aqueous mixture;
(b) sulfiding, in an initial reaction zone, the aqueous mixture of step (a) with a gas comprising hydrogen sulfide to a dosage greater than 8 SCF of hydrogen sulfide per pound of Group VIB metal to form a slurry;
(c) promoting the slurry with a Group VIII metal compound;
(d) mixing the slurry of step (c) with a hydrocarbon oil having a viscosity of at least 2 cSt@ 212° F. to form an intermediate mixture;
(e) combining the intermediate mixture with hydrogen gas in a second reaction zone, under conditions which maintain the water in the intermediate mixture in a liquid phase, thereby forming an active catalyst composition admixed with a liquid hydrocarbon; and
(f) recovering the active catalyst composition.
7. The process of claim 1 , in which at least 90 wt % of the feed is converted to lower boiling products.