A Simple Technique to Forecast CO2 Flood Performance

This paper presents a technique which takes a one-dimensional (1D) compositional simulation output and scales the results up to an entire pattern. The scale-up procedure takes into account the pore volume and heterogeneity of the pattern. Several parameters are adjusted to match the production history allocated to the pattern. Once a model has been developed to reproduce the waterflood performance, the initial date and target volume of carbon dioxide (CO₂) injection is specified.

This scale-up technique has been successfully applied to forecast the performance of the McElmo Creek Unit CO₂ project (SE Utah), in operation since 1985. A history match was obtained for each of the 119 patterns in the project. In the mature CO₂ flood patterns, both secondary and tertiary performance was matched. The composite of all the pattern forecasts closely follows the actual production history. The production and injection forecasts will be used to determine future water handling and gas processing requirements, and will assist with planning the timing of further field development.