Converting ethane to liquid fuels and chemicals

Patent metadata

Field	Value
Publication number	US-10087380-B2
Application number	US-201414571763-A
Country	US
Kind code	B2
Filing date	Dec 16, 2014
Priority date	Jun 5, 2013
Publication date	Oct 2, 2018
Grant date	Oct 2, 2018

Abstract

A process for converting ethane to liquid fuels may involve directing an ethane stream into an ethane cracking unit to produce an intermediate hydrocarbon stream and a raw ethylene stream; fractionating the intermediate hydrocarbon stream into a gasoline fraction and a diesel fraction; introducing the raw ethylene stream into an oligomerization unit; contacting the raw ethylene stream with an oligomerization catalyst to produce a liquid hydrocarbon stream and an off-gas stream; recycling an off-gas recycle stream from an off-gas stream of the oligomerization unit separation unit to an inlet of the oligomerization reactor; introducing at least part of the off-gas stream into a hydrogenation reactor to remove unconverted olefins; separating a hydrogen component and a plurality of light paraffin components in a post hydrogenation reactor separation unit using a PSA technology or membrane technology; and recycling the light paraffins stream into the ethane cracking unit.

First claim

The invention claimed is:

1. A process for converting ethane to liquid fuels comprising:
directing an ethane stream into an ethane cracking unit in a first stage to produce an intermediate hydrocarbon stream and a raw ethylene stream;
contacting the raw ethylene stream with an oligomerization catalyst to produce liquid hydrocarbon stream and an off-gas stream;
introducing at least part of the off-gas stream into a hydrogenation reactor to saturate olefins yielding a mixture of a plurality of light paraffin components and a hydrogen component from the hydrogenation reactor;
separating the hydrogen component and the plurality of light paraffin components in a post hydrogenation reactor separation unit using a PSA technology or membrane technology; and
recycling the light paraffins stream into the ethane cracking unit.

2. The process according to claim 1 , further comprising: removing a hydrogen stream from the raw ethylene stream.

3. The process according to claim 1 , further comprising: recycling an off-gas recycle stream from the separation unit off-gas stream to an inlet of the oligomerization reactor.

4. The process according to claim 1 , wherein the oligomerization catalyst is selected from solid phosphoric acid catalyst, zeolite catalyst, or Ni-containing catalyst.

5. A process for converting ethane to liquid fuels comprising:
directing an ethane stream into an ethane cracking unit in a first stage to produce an intermediate hydrocarbon stream and a raw ethylene stream;
removing a hydrogen stream from the raw ethylene stream;
contacting the raw ethylene stream with an oligomerization catalyst to produce a liquid hydrocarbon stream and an off-gas stream;
introducing at least part of the off-gas stream into a hydrogenation reactor to saturate olefins;
yielding a mixture of a plurality of light paraffin components and a hydrogen component from the hydrogenation reactor;
separating the hydrogen component and the plurality of light paraffin components in a post hydrogenation reactor separation unit using a PSA technology or membrane technology; and
recycling the light paraffins stream into the ethane cracking unit.

6. The process according to claim 5 , further comprising: recycling at least a portion of the off-gas stream to an inlet of the oligomerization reactor.

7. The process according to claim 5 , wherein the oligomerization catalyst is selected from solid phosphoric acid catalyst, zeolite catalyst, or Ni-containing catalyst.

8. A process for converting ethane to liquid fuels comprising:
directing an ethane stream into an ethane cracking unit in a first stage to produce an intermediate hydrocarbon stream and a raw ethylene stream;
fractionating the intermediate hydrocarbon stream into a gasoline fraction and a diesel fraction;
removing a hydrogen stream from the raw ethylene stream;
introducing the raw ethylene stream into a first oligomerization unit;
contacting the raw ethylene stream with an oligomerization catalyst in the first oligomerization unit to produce a treated stream;
introducing the treated stream to an oligomerization unit separation unit and producing a liquid hydrocarbon stream comprising hydrocarbons containing four or more carbons and an off-gas stream comprising hydrocarbons containing three or less carbons;
recycling an off-gas recycle stream from the off-gas stream to an inlet of the oligomerization reactor;
introducing at least part of the off-gas stream into a hydrogenation reactor to remove unconverted olefins;
yielding a mixture of a plurality of light paraffin components and a hydrogen component from the hydrogenation reactor;
separating a hydrogen component and a plurality of light paraffin components in a post hydrogenation reactor separation unit using a PSA technology or membrane technology; and
recycling the plurality of light paraffins components into the ethane cracking unit.

9. The process according to claim 8 , further comprising: utilizing solid phosphoric acid catalyst, zeolite catalyst, or Ni-containing catalyst within the oligomerization reactor.

10. The process according to claim 8 , further comprising:
providing a second oligomerization unit; and
regenerating a catalyst of the second oligomerization unit when the first oligomerization unit is treating the raw ethylene stream.

11. A process for converting ethane to liquid fuels comprising:
directing an ethane stream from a gas well to a gas fractionator;
producing a post-fractionator ethane stream from the gas fractionator;
directing the post-fractionator ethane stream into a thermal activation unit;
producing an activated stream from the thermal activation unit by heating the post-fractionator ethane stream in the thermal activation unit;
directing the activated stream into a quench tower;
producing in the quench tower, a first C 4 + hydrocarbon stream and a quenched stream;
directing the quenched stream into a first separation unit;
removing hydrogen in a hydrogen stream from the quenched stream in the first separation unit;
directing the quenched stream without hydrogen, as a first separation unit exiting stream into a conversion unit;
within the conversion unit, treating the first separation unit exiting stream with a catalyst and producing a converted product stream; and
directing the converted product stream into a second separation unit and producing a second C 4 + hydrocarbon stream and a C 3 + and lighter hydrocarbon stream.

12. The process according to claim 11 , further comprising: directing the C 3 + and lighter hydrocarbon stream back into the thermal activation unit.

13. The process according to claim 11 , wherein the activated stream is a raw ethylene stream.

14. The process according to claim 11 , wherein the catalyst is a metal-based catalyst.

15. The process according to claim 11 , wherein the catalyst is a Nickel based catalyst.

16. The process according to claim 11 , wherein the catalyst is Ni-ZSM-5.

Assignees

• Phillips 66 Co

Inventors

• Yao Jianhu
• Ghonasgi Dhananjay
• Choudhary Tushar
• Ewert Warren

Classifications

• C10G69/126 Primary

  polymerisation, e.g. oligomerisation · CPC title

• C10G9/36

  with heated gases or vapours · CPC title

• C10G45/00

  Refining of hydrocarbon oils using hydrogen or hydrogen-generating compounds · CPC title

• C10G50/00

  Production of liquid hydrocarbon mixtures from lower carbon number hydrocarbons, e.g. by oligomerisation · CPC title