Improving Recovery of Liquids from Shales Through Gas Injection

Abstract

This thesis investigates the use of gas injection for improving liquids recoveries from oil and condensate containers in shale reservoirs. The objective is accomplished by building simulation models of a shale reservoir that contains gas, condensate and oil. In these shales, the gas container is at the bottom, the condensate container in the middle, and the oil container at the top of the structure. Results show that liquids recoveries can be increased by injecting dry gas from the lower part of the structure and recycling gas from the condensate container. The reservoir model is coupled with wells and surface facilities models. This study demonstrates that the proper design of wellbore and surface installations is critical as they can also lead to significant improvements in liquid recoveries. The effect of refracturing horizontal wells is also investigated. It is found that refracturing can yield the same incremental production obtained by infill drilling.