CO2 Foam Pilot in a West Texas Field: Design, Operation and Results

Abstract

Abstract In this paper, we describe the design, implementation and results of a CO2 foam pilot in a mature CO2 flood in West Texas. The objective of the pilot was to demonstrate improved conformance/sweep efficiency of the CO2 foam over CO2 WAG injection. Laboratory experiments to guide design of the flood and the monitoring program to understand and model flood performance are described. Monitoring included rate and pressure tracking, injection profiles and inter-well tracer programs before and during the foam flood. While changes in injection rate and injection profile confirmed the formation of strong foam near the wellbore and redistribution of fluids in the injectors, oil response was weak, with significant oil gain observed in one of the four patterns. The gas production rate also changed very slightly from the baseline conditions. The comprehensive monitoring program in this pilot provides new insights into effectiveness of CO2 foam in actual field applications. The results from this pilot may help to better screen and design future foam injection pilots.