Experimental Investigation of the Feasibility of Steam/Chemical Steam Flooding Processes through Horizontal Wells

Abstract

Abstract Laboratory studies and field applications have strongly established steam flooding as a valuable and remarkable recovery technique for both vertical and horizontal wells. This experimental study presents an investigation of the potential of enhancing tertiary oil recovery of heavy crude oil using steam, caustic steam, surfactant steam, and caustic-surfactant steam flooding through horizontal wells. The oil recovery of each process is measured and a comparison is carried out. The experiments were conducted using a box-shaped sandpack equipped with a centered horizontal well. The followed experimental procedure used the configuration of a horizontal steam injector with a vertical producer. The results of the dynamic experiments indicated that steam flooding through a horizontal well substantially improved oil recovery. Addition of caustic (sodium hydroxide) or surfactant (X-Triton-100) to steam drive recovered additional oil of 2.7 % IOIP or 5.6 % OOIP, respectively, than conventional steam flooding for water flooded reservoirs through horizontal well. In addition, the use of mixed solution of caustic and surfactant into steam current potentially enhanced oil recovery by almost 7.5 % IOIP than conventional steam flooding through horizontal wells for water flooded reservoirs. The above results indicate that steam and/or suggested chemical steam techniques are efficient methods for recovering heavy oil from water-flooded reservoirs. Key Words: Thermal methods, Chemical methods, Horizontal wells, and Fluid flow. Introduction Steam flooding is considered a complex oil displacement process involving simultaneous heat, mass, and fluid transport. In addition, steam drive is a powerful thermal recovery process for recovering high gravity crude oils because steam appears to be one of the most efficient hot injection fluids because of its large gross heat capacity. There is considerable agreement that steam flood is a very efficient mean for reducing the residual oil saturation. Steam flooding in vertical wells has been proven to have remarkable potential for increasing oil recovery of heavy crude oils. A tendency of steam to override the bottom half of the producing formation is considered to be the main drawback of the process. Another problem for steam flood in vertical wells is that the non-optimized of well geometry to the expected steam zone.