Development options in marginal fields are sometimes limited, driven primarily by economics, license period, size of asset and regulatory constraints. The Operators objective is to economically develop the reserves from multiple zones with fewer wells, whilst maintaining mandatory reservoir surveillance and accounting. Intelligent or smart completions are at various level of maturity, depending on the well architecture, application, and measurement & control devices. The concept of using smart completions within the marginal field environment has historically been limited.
The conventional completion practices in marginal fields with stacked reservoirs are mostly multistring or selective designs. A strong driver for smart wells in a marginal field is the desire for simultaneous exploitation of multiple reservoirs, lower capex (fewer wells), reduced opex, smaller footprints and effective zonal control. Remote zonal control is desirable, due to the locations accessibility, which makes intervention prohibitive and with increased health, safety, and environmental (HSE) risks.
This paper will focus on the application of an intelligent completion technique in Okporhuru, a partially appraised field in the Niger Delta area of Nigeria comprising stacked reservoirs. The field is classified marginal due to limited data, low first pass initial oil volume and remoteness from production facilities, amongst others. This paper will detail the modelling technique, flow control valve (FCV) design philosophy, and requisite monitoring to meet target zonal flow contributions. Application of a compact, modular, multi-zonal smart completion solution (IZC), pre installation design, deployment considerations and production allocation methodology will highlight the considerations for selection of a unique sand control technique in this partially appraised field.