Gas Injection in Lower Cretaceous Reservoirs (Phase II)

The Lower Cretaceous Reservoirs in the Valdemar field are low permeable chalk reservoirs which are generally under exploited. A further increase in recovery needs additional production energy and reduction in the residual oil saturation.

Gas injection has proven to be an effective and successful EOR method worldwide and its feasibility for the Valdemar field will be studied here.

 

Gas injection is a potential method to supplement energy to reservoir production and to enhance oil recovery. The proposed research will investigate gas injection into the Lower Cretaceous reservoirs with the aim of quantifying the potential of enhanced oil recovery for these reservoirs through various gas injection options.

 

The injection gas will cover mainly non-CO2 gas sources like hydrocarbon gas, nitrogen, and flue gas. The investigation will integrate experimental study and thermodynamic modelling of fluid behaviour under gas injection, laboratory study of gas flooding processes, and compositional reservoir simulation of conceptual and sector models representative for candidate reservoirs.

 

The project consists of two phases: Phase I (1.5 years) is aimed to carry out a feasibility study through simulation of conceptual models. This phase involves basic experimental studies on fluids and core flooding. Phase II (2 years) is aimed to provide evaluation based on sector models where more details are included. More advanced and detailed experimental and modelling work are needed in this phase.

 

The project is expected to provide reliable models for future full-field simulations toward pilot tests and decision-making on development strategies. The detailed experimental and modelling studies will also help get insight into gas injection in low permeable Lower Cretaceous reservoirs.

 

The project participants include CERE, DHRTC and GEUS. The major research directions include fluid phase behaviour under gas injection, core flooding and diffusion experiment, and compositional reservoir simulation.

 

Main supervisor: Wei Yan

Co- supervisor: Erling H. Stenby