Injection control in first dump flood application in deepwater Gulf of Mexico

A client offshore Louisiana in the deepwater Gulf of Mexico needed to perform a controlled injection into two separate sands units with different injection rates for each zone, with up to 35,000 bwid of water produced and dumped from a shallower sand unit.

Specifically, the client needed to distribute the injection on a 50%/50% rate and a 15%/85% rate, respectively, for the life of the well to optimize net present value (NPV) of the project.

Controlled injection has never before been used in the deepwater gulf; this design would be the first dump flood system. In prior wells with injection, full open sliding sleeves have been used. Given the innovative nature of the required solution, Welltec® was a natural fit for this job.

To implement the controlled injection system for the client, Welltec selected the 312 Welltec Flow Valve (WFV) Multi-Position (MP) and conducted extensive flow modelling for results. The reservoir expert and a team of reservoir engineers performed modelling to select the choke sizes and the WFV positions to achieve the client’s desired 50%/50% and 15%/85% distribution.

Modeling was performed with a steady-state numerical simulator in collaboration between Welltec’s reservoir modeling team and the client’s reservoir engineers.

Once the optimum parameters were selected, the manufacturing process started with the selection of specific choke sizes to achieve the desired injection rate per zone.

The WFV were deployed with the completion string. Five months after deployment, they were opened via the Well Stroker® and a shifting tool.

The client operates in the deepwater Gulf of Mexico and has sought technological adoptions that enable them to work smarter. Impressed by Welltec’s innovative completions solutions, the client selected the WFV MP for its simple yet effective design and its ability to selectively choke the flow area to achieve the required injection rates.

Once the WFV were actuated, they effectively distributed the injection flow according to the client’s expectations. The WFV helped accomplish their goals of injection distribution, enabling the controlled injection via dump flood into two different zones with the desired rates of injection.

The solution provided controlled injection with variable rates into the two upper and lower producer sands. This technique enables a cost-effective and reliable solution that can increase the overall NPV of a field by increasing recovery. Welltec’s WFV can be applied to any type of injector well.