Hydroconversion processes with ebullated bed reactors and inter-stage water addition
Embodiments of the disclosure include processes for hydroconversion of hydrocarbon feedstocks in ebullated bed reactor systems. In particular, the systems comprise two or more ebullated bed reactors comprising catalyst particles, one or more inter-stage separation vessels, which are in fluid communication, and allow for the introduction of an additional solvent into the system between the final inter-stage separation vessel and the final ebullated bed reactor in the flow path. The processes include the addition of a solvent comprising water to an inter-stage liquid product prior to contact with the final ebullated bed reactor, which improves catalytic performance.
1 . A process for hydroconversion of a hydrocarbon feedstock comprising:
(i) contacting the hydrocarbon feedstock and hydrogen in a first ebullated bed reactor containing first catalyst extrudate to produce a first liquid stream and a first mixed stream, the first mixed stream consisting of liquid products and gas products;
(ii) separating the first mixed stream in an inter-stage separation vessel to form an inter-stage gas product and an inter-stage liquid product;
(iii) combining the inter-stage liquid product with a solvent comprising water in an amount of about 0.001 weight % to about 10 weight % of the inter-stage liquid product;
(iv) contacting the inter-stage liquid product and the solvent in a second ebullated bed reactor containing second catalyst extrudate to produce a second liquid stream and a second mixed stream, the second mixed stream consisting of liquid products and gas products;
(v) separating the second mixed stream in a high temperature and high pressure separation vessel to form a final gas product and a final liquid product; and
wherein at least a portion of the first liquid stream is returned to the first ebullated bed reactor containing the first catalyst extrudate and at least a portion of the second liquid stream is returned to the second ebullated bed reactor containing the second catalyst extrudate.
2 . The process of claim 1 , wherein the hydrocarbon feedstock comprises residuum hydrocarbon feedstock.
3 . The process of claim 2 , wherein the residuum hydrocarbon feedstocks are selected from refinery and other hydrocarbon streams which include some contaminant metals.
4 . The process of claim 2 , wherein the residuum hydrocarbon feedstocks comprise petroleum atmospheric residue, vacuum residue, deasphalted oil, deasphalter pitch, hydrocracked atmospheric tower bottom, vacuum tower bottom, straight run vacuum gas oil, hydrocracked vacuum gas oil, fluid catalytically cracked (FCC) slurry oils, or a combination thereof.
5 . The process of claim 1 , wherein the first catalyst extrudate and the second catalyst extrudate comprise one or more elements selected from Groups 4-12 of the Periodic Table of the Elements.
6 . The process of claim 5 , wherein the first catalyst extrudate and the second catalyst extrudate comprise one or more of nickel, cobalt, tungsten, molybdenum and combinations thereof and wherein the first catalyst extrudate has a pore volume of 0.7 to 1.0 cc/gm and the second catalyst extrudate has a pore volume of 0.6 to 0.8 cc/gm.
7 . The process of claim 6 , wherein the nickel, cobalt, tungsten, molybdenum and combinations thereof are supported on a porous substrate such as silica, alumina, titania, or combinations thereof.
8 . The process of claim 1 , wherein the first catalyst extrudate and the second catalyst extrudate are fully or partially sulfided prior to or during use in the ebullated bed reactors.
9 . The process of claim 1 , wherein the hydrocarbon feedstock and hydrogen are heated and combined prior to entering the first ebullated bed reactor containing the first catalyst extrudate.
10 . The process of claim 1 , wherein the process further comprises contacting the first mixed stream of step (i) with an additional ebullated bed reactor containing additional catalyst extrudate prior to step (ii).
11 . The process of claim 1 , further comprising separating the first mixed stream in an inter-stage separation vessel to form an inter-stage gas product and an inter-stage liquid product prior to step (ii).
12 . The process of claim 1 , wherein the process comprises one or more additional ebullated bed reactors comprising additional catalyst extrudate and, optionally, one or more additional inter-stage separation vessels, and wherein the solvent is combined with the inter-stage liquid product of a final inter-stage separation vessel in the process and the combined inter-stage liquid product and solvent are contacted with a final ebullated bed reactor containing final catalyst extrudate in the process.
13 . A process for hydroconversion of a hydrocarbon feedstock comprising:
(i) contacting the hydrocarbon feedstock and hydrogen in a first ebullated bed reactor containing first catalyst extrudate to produce a first liquid stream and a first mixed stream, the first mixed stream consisting of liquid products and gas products;
(ii) separating the first mixed stream in an inter-stage separation vessel to form an inter-stage gas product and an inter-stage liquid product;
(iii) contacting the inter-stage liquid product and a solvent in a second ebullated bed reactor containing second catalyst extrudate to produce a second liquid stream and a second mixed stream, the second mixed stream consisting of liquid products and gas products;
(iv) separating the second mixed stream in a second inter-stage separation vessel to form a second inter-stage gas product and a second inter-stage liquid product;
(v) combining the second inter-stage liquid product with a second solvent comprising water in an amount of about 0.001 weight % to about 10 weight % of the second inter-stage liquid product;
(vi) contacting the second inter-stage liquid product and the second solvent in a third ebullated bed reactor containing third catalyst extrudate to produce a third liquid stream and a third mixed stream consisting of liquid products and gas products;
(vii) separating the third mixed stream in a high temperature and high pressure separation vessel to form a final gas product and a final liquid product; and
wherein at least a portion of the first liquid stream is returned to the first ebullated bed reactor containing the first catalyst extrudate, at least a portion of the second liquid stream is returned to the second ebullated bed reactor containing the second catalyst extrudate and at least a portion of the third liquid stream is returned to the third ebullated bed reactor containing the third catalyst extrudate.
14 . The process of claim 13 , wherein the hydrocarbon feedstock comprises residuum hydrocarbon feedstock.
15 . The process of claim 14 , wherein the residuum hydrocarbon feedstocks are selected from refinery and other hydrocarbon streams which include some contaminant metals.
16 . The process of claim 14 , wherein the residuum hydrocarbon feedstocks comprise petroleum atmospheric residue, vacuum residue, deasphalted oil, deasphalter pitch, hydrocracked atmospheric tower bottom, vacuum tower bottom, straight run vacuum gas oil, hydrocracked vacuum gas oil, fluid catalytically cracked (FCC) slurry oils, or a combination thereof.
17 . The process of claim 13 , wherein the first catalyst extrudate, the second catalyst extrudate, and the third catalyst extrudate comprise one or more elements selected from Groups 4-12 of the Periodic Table of the Elements.
18 . The process of claim 17 , wherein the first catalyst extrudate, the second catalyst extrudate, and the third catalyst extrudate comprise one or more of nickel, cobalt, tungsten, molybdenum and combinations thereof and wherein the first catalyst extrudate has a pore volume of 0.7 to 1.0 cc/gm and the second catalyst extrudate and third catalyst extrudate have a pore volume of 0.6 to 0.8 cc/gm.
19 . The process of claim 18 , wherein the nickel, cobalt, tungsten, molybdenum and combinations thereof are supported on a porous substrate such as silica, alumina, titania, or combinations thereof.
20 . The process of claim 13 , wherein the first catalyst extrudate, the second catalyst extrudate, and the third catalyst extrudate are fully or partially sulfided prior to or during use in the ebullated bed reactors.