Investigation of inert gas injection through horizontal wells

Downward displacement of oil by inert gas injection in oil reservoirs results in very high oil recovery efficiencies. Advances made in horizontal drilling technology and increased understanding of the mechanisms and conditions that maximize recovery efficiencies can make the inert gas injection process feasible for a wide variety of oil reservoirs. In this study, laboratory investigation was conducted for the recovery of heavy oil from a 3-D physical model packed with 26 degrees API gravity oil, brine and crushed limestone. A total of 7 runs were conducted using the 3-D physical model with 30 x 30 x 6 cm(3) dimensions. Two groups of well configurations were mainly used: ( 1) horizontal injection and point production wells and ( 2) horizontal injection and horizontal production wells. In continuous N-2 injection, highest recovery was obtained by horizontal injection-horizontal production well configuration.