Gas enhanced oil recovery methods for offshore oilfields: Features, implementation, operational status

Nowadays, enhanced oil recovery (EOR) methods have been evaluated both for onshore and offshore oilfields. However, the conditions for using EOR methods in offshore fields are more complex due to the unique features of the infrastructure, transportation facilities and geological conditions. The experience gained from offshore gas EOR (gEOR) pilot projects has shown effective methods for increasing oil production at a later stage of field development. The technical knowledge base gained has been analyzed in this paper, which includes an analysis of the advantages and disadvantages of offshore projects and operational experience with gas and water-gas flooding in offshore environments. A history of implemented EOR projects in offshore oil fields from 1970 to the present and an evaluation of the application of different injection methods with hydrocarbon gas, CO 2 and nitrogen is presented sequentially.