Equalization of the Water Injection Profile of a Subsea Horizontal Well: A Case History

Abstract:

This paper focuses on the first global installation of a water injector well with a lower completion system that incorporates both premium sand control screens and water injection profile equalization.  The equalization of the water injection profile of horizontal wells has been a key issue in many development projects worldwide and has the potential to increase the reservoirs ultimate recovery by increasing the water sweep efficiency.

Inflow Control Devices integrated with premium sand control screens have a long history of application in production wells.  In these cases the main objective is to create a uniform inflow profile along the horizontal section, delaying unwanted water and gas production and increasing oil recovery.  The method through which Inflow Control Devices equalize the inflow of oil can also be used to equalize the outflow of water.  Historically, sand control completions for water injection wells include stand-alone conventional screens and open-hole gravel packs.  Stand-alone conventional screen completions do not provide equalization of the water injection profile.  Open-hole gravel packs provide for an effective acid treatment of the water injector well but present operational risks, high costs, as well as expensive rig time.

The installation was carried out in a subsea horizontal sea water injector well in the Campos Basin, offshore Brazil.  The paper presents the overall completion plan, the lower completion installation, the acid treatment through the Inflow Control Devices, and the initial water injection results based on production logs and water injectivity tests.  The main concerns during the planning phase are discussed, highlighting the procedures adopted to overcome them.

The good initial results have created the expectation of many applications of this system in Campos Basin.   It is believed that sharing this information will benefit many operators with horizontal water inject