Converting ethane to liquid fuels and chemicals

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.