Catalytic hydrogenation process utilizing multi-stage ebullated bed reactors

• US 6,270,654 B1
• Filed: 05/29/1998
• Issued: 08/07/2001
• Est. Priority Date: 08/18/1993
• Status: Expired due to Term

• Current Assignee: IFP North America, Inc.
• Original Assignee: IFP North America, Inc.
• Inventors: MacArthur, James B., Peer, Eric D., Colyar, James J.
• Primary Examiner(s): NORTON, NADINE GEORGIANNA
• Application Number:
  US09/087,181
• Time in Patent Office: 1,166 Days
• Field of Search: 208/58, 208/57, 208/59, 208/108, 208/143, 208/153, 208/157
• US Class Current: 208/57
• CPC Class Codes: C10G 2300/4081 Recycling aspects
• CPC Class Codes: C10G 47/26 suspended in the oil, e.g. slurries
• CPC Class Codes: C10G 65/10 including only cracking steps

Abstract

A process for catalytic multi-stage hydrogenation of heavy carbonaceous feedstocks using catalytic ebullated bed reactors is operated at selected flow and operating conditions so as to provide improved reactor operations and produce increased yield of lower boiling hydrocarbon liquid and gas products. The disclosed process advantageously takes advantage of an external gas/liquid separation unit associated with the first stage reactor to allow for a more efficient and effective catalytic hydrocracking process. The more efficient process is primarily a result of the increased catalyst loading and lower gas hold-up in the ebullated reactors.

Claims

1. A process for catalytic multi-stage ebullated bed hydrogenation of heavy hydrocarbonaceous feedstocks for producing lower boiling hydrocarbon liquids and gases, the process comprising:

(a) feeding a heavy hydrocarbonaceous liquid vacuum residue feedstock having contaminant metal up to 1000 wppm, 10-50 wt. % Conradson Carbon Residue; and

50%-90 vol % normally boiling above 975°

F. together with hydrogen gas into a first stage catalytic ebullated bed reactor, said first stage catalytic ebullated bed reactor having no internal gas/liquid separation device, at liquid space velocity of 0.2-2.0 volume of feed per hour per volume of reactor (Vf/hr/Vr), a catalyst replacement rate of 0.05-0.5 Lb/Bbl (per stage), catalyst bed expansion of 25-75%, and at catalyst space velocity of 0.03-0.33 bbl/day/lb catalyst, providing upward superficial gas velocity of 0.02-0.30 ft/sec while maintaining reaction temperatures of 700-850°

F., and 800-3,000 psi hydrogen partial pressure at the reactor outlet, and producing a first stage reactor effluent material;

(b) phase separating the first stage effluent using an external gas/liquid separator, into a gas portion and a first liquid portion, and passing the first liquid portion to a second stage catalytic ebullated bed reactor maintained at near the reaction conditions of step (a), and producing a second stage effluent material;

(c) phase separating the second stage effluent material into a gas and a liquid second portion;

(d) fractionating said second liquid portion to produce a medium-boiling hydrocarbon liquid fraction product having normal boiling range of 400-650°

F. and a vacuum bottoms fraction material having a normal boiling point above about 650°

F.; and

(e) recycling said vacuum bottoms fraction material directly to said first stage catalytic ebullated bed reactor to provide a recycle volume ratio of the vacuum bottoms material to fresh feedstock of 0-1.0/1;

whereby steps a-e result in greater than 50% vol. % conversion of the 975°

F.⁻

fraction in the feedstock to lower-boiling hydrocarbon liquid and a desulfurization of greater than 65 wt. %.

2. A hydrogenation process according to claim 1, wherein said first stage reaction conditions are 750-840°

F. temperature, 1,000-2,500 psig hydrogen partial pressure at the reactor outlet, 0.40-1.2 V_f/Hr/V_r liquid space velocity and 0.04-0.20 Bbl/day/lb. catalyst space velocity.

3. A hydrogenation process according to claim 1, wherein said second stage reaction conditions are 750-840°

F. temperature, 1,000-2,500 psig hydrogen partial pressure at the reactor outlet 0.40-1.2 V_f/Hr/V_r liquid space velocity, and 0.04-0.20 Bbl/day/lb. catalyst space velocity.

4. A hydrogenation process according to claim 2, wherein the reactor superficial gas velocity is 0.025-0.20 ft./sec.

5. A hydrogenation process according to claim 3, wherein the reactor superficial gas velocity is 0.025-0.20 ft./sec.

6. A hydrogenation process, according to claim 1, wherein a height distance of 5-10 ft. is maintained in the first stage catalytic reactor between the ebullated bed upper level and the reactor outlet connection.

7. A hydrogenation process according to claim 1, wherein said recycled vacuum bottoms material has a normal boiling point above about 900°

F. and is recycled to the first stage reactor at a volume ratio of vacuum bottoms material to fresh feed of 0-1.0/1 to achieve 65-90 vol. % conversion of the feedstock to lower-boiling hydrocarbon liquid products.

8. A hydrogenation process according to claim 1, wherein the volume ratio of vacuum bottoms material recycled to said first stage reactor to the fresh feedstock being fed to said first stage reactor is about 0.2/1-0.7/1.

9. A hydrogenation process according to claim 1, wherein the catalyst used in said first stage and second stage reactors contains 2-25 wt. % total active metals and has total pore volume of 0.30-1.50 cc/gm, total surface area of 100-400 m²/gm and average pore diameter of at least 50 angstrom units.

10. A hydrogenation process according to claim 1, wherein the catalyst used in the first stage and second stage reactors has total pore volume of 0.40-1.20 cc/gm, total surface area of 150-350 m²/gm and average pore diameter of 80-250 angstrom units.

11. A hydrogenation process according to claim 1, wherein the catalyst used in said second stage catalytic reactor contains 5-20 wt. % cobalt-molybdenum on alumina support material.

12. A hydrogenation process according to claim 1, wherein the catalyst used in said second stage catalytic reactor contains 5-20 wt. % nickel-molybdenum on alumina support material.

13. A hydrogenation process according to claim 1, wherein used catalyst is withdrawn from said second stage catalytic reactor and passed to said first stage catalytic reactor as the catalyst addition therein, and fresh catalyst replacement rate of 0.05-0.50 pound catalyst per barrel of the fresh feedstock is provided to said second stage reactor.

14. A hydrogenation process according to claim 1, wherein the second stage reactor temperature is 0-50°

F. below the first stage reactor temperature so as to prehydrogenate the feedstock in the first stage reactor so that 50-100 vol. % hydroconversion of 975°

F.⁺ residua is achieved in the second stage reactor, and the recycle rate is 0.2-0.7/1.

15. A hydrogenation process according to claim 1, wherein the feedstock is petroleum residua material having 50-90 vol. % normally boiling above 975°

F. and containing 10-50 wt. % Conradson Carbon Residue (CCR) and greater than 100 wppm total metals.

16. A hydrogenation process according to claim 1 wherein the feedstock is bitumen.