Techniques in the upstream oil and gas industry

Apparatus for offshore CO2-based EOR or for offshore CO2-based EGR comprising:

• an integrated offshore facility provided with:
• at least one on-site storage means, selected from tanks and vessels, adapted to store CO2 in a state selected from liquid and super-critical states, and equipment for marine transfer of CO2 in said state,
• equipment for injecting CO2 into a sub-sea oil field for EOR or into a sub-sea natural gas field for EGR;
• and
• equipment for recovering oil and/or natural gas from a resulting production stream;
• and at least one carrier vessel adapted to deliver CO2 in said state from at least one CO2 storage site remote from the integrated offshore facility, preferably an onshore site, to the said integrated offshore facility.

An integrated offshore oil or natural gas facility comprising:

• at least one on-site storage means, selected from tanks and vessels, adapted to store CO2 in a state selected from liquid and super-critical states, and equipment for marine transfer of CO2 in said state,
• equipment for injecting CO2 into a sub-sea oil field for EOR or into a sub-sea natural gas field for EGR;
• and
• equipment for recovering oil and/or natural gas from a resulting production stream.