A Novel Method of Forecasting CO2 Flood Performance for Various WAG Injection Schemes by Analyzing Injection Pulses

Abstract

Abstract This paper presents a new method for generating dimensionless CO2 flood forecast prototypes for various injection schemes from an existing prototype. Given an existing prototype, the method described in this paper can predict an appropriate prototype for an alternating injection schedule. This methodology enables engineers to quickly generate forecast prototypes by analyzing the oil/gas production response from breaking down existing prototypes (developed either from simulation or from analog field performance) into injected CO2 pulses. A Microsoft Excel with VBA program (PULSER) based on this methodology has been successfully utilized to generate the prototypes for the fluid streams forecast of several West Texas/New Mexico CO2 flooding projects. When compared to reservoir simulation, the Pulse method is much faster in generating new prototypes and more flexible in accomodating different injection scenarios. The results from this method, full field simulation, and blind testing actual field data are remarkably consistent.