Optimizing Oil Recovery and Carbon Dioxide Storage in Heavy Oil Reservoirs

摘要

We study the design of enhanced oil recovery in heavy oil reservoirs combined with CO2 storage using field-scale reservoir simulation. We consider properties typical of fields offshore Trinidad and Tobago with oils whose density ranges between 940 and 1010 kg/m~3 (9-18 degrees API). We first tune a three-parameter Peng-Robinson equation of state to match measured PVT data. We use experimental design to study the influence of oil properties, phase behavior and injection design on oil recovery and net CO2 storage. Carbon dioxide injection into heavy oil reservoirs enhances oil recovery through the mechanisms of crude viscosity reduction, oil swelling and immiscible gas drive. The process involves significant recycling of the injected CO2, but the reservoir is managed to keep as much of the injected CO2 as possible underground.