ABSTRACT
It is estimated that for every barrel of oil produced, three barrels of water are produced (Bailey et al, 2000). The objectives of this research were to identify the issues that lead to high water cut in oil and gas wells and to provide solutions to these issues, to develop production plans for wells with a high water cut and using the PROSPER Nodal Analysis Software to optimize the well’s performance in order to maximize the production rate.
A well operated by Midwestern Oil and Gas within the Umusadege Field, OML 56 located in the northern area of Niger Delta basin was used for this research.
Sensitivity analysis was conducted with the aid of IPM Prosper software in this research for modelling well and analyzing data. Prosper being a well modelling software that works discretely or could be integrated with other IPM software. The process used for achieving the research objectives are; definition of mathematical model, Quality assessment and Quality check (QAQC) of Data, Initialization for fluid PVT, Actual well design (to include the deviation survey, surface equipment, downhole equipment, geothermal and heat capacities, parameter specification and the average heat capacities), Initialization of rock properties, Modelling of system Inflow Performance Relationship and the Well Test Analysis.
It was found that at high water cut, the use of water control methods which includes Mechanical Shutoff Methods such as the use ofBridge plugs, Straddle packers, Tubing patches, Cement, Sand plugs and Expandable Tubular or Chemical Shutoff Methods such asMicro matrix cements, Polymers, Micro particle blends, Foamed systems, Resins/particulate chemical blend, and the use of Gels/gelant in the well are operations to be considered depending on how favorable it is economically and from the sensitivity analysis conducted, it would be best that a well with high water cut problem is produced using a large choke size in order to reduce the back pressure from the well head at the system and increase in the gas lift’s gas rate or use of gas injection are secondary drive mechanisms that could be employed to ensure continuous production of oil.
