ABSTRACT

Huge amount of hydrocarbon in place is left unrecovered. Integrated reservoir management, in addition to the use of new technologies improves hydrocarbon recovery. Intelligent completion is one of the technologies which enhance reservoir management thereby improving the hydrocarbon recovery.

This work presents a review of intelligent completion technology, guidelines to evaluate the decision whether or not to implement intelligent completion and evaluates field cases of intelligent completion installation.

The case studies were derived from four fields where intelligent completions have been implemented. Comparison of intelligent completion with non-intelligent completion was based on ease of data acquisition for reservoir management, incremental oil production and profitability criteria. The yard sticks used for economic analysis include the net present value, discounted payout period, profitability index and growth rate of return.

The results from the study show that reliable intelligent completion improves reservoir management by enabling data acquisition and well monitoring. Employing intelligent well completions in reservoir management can lead to 21% to 38% increase in oil recovery and 17% to 41% increase in NPV compared to non-intelligent completion. It must be pointed out that intelligent system failure may render intelligent completion projects economically unattractive.

The results of this study can be used to evaluate the feasibility of executing an intelligent completion project; especially in fields were intelligent completion is yet to be implemented as a tool for reservoir management.

CHAPTER 1

INTRODUCTION

1.1 INTRODUCTION

Reserves are the main asset of the exploration and production (E&P) industry. Every E&P firm aims at maximizing its total profit in the long run, hence the industry aims at enhancing ultimate recovery of a field, cost efficiently. However, most of the hydrocarbons in place are not recovered; about 35% of hydrocarbons in place are recovered leaving behind the remaining 65%. The need to improve recovery from the huge amount of remaining hydrocarbons in place around the world requires sound reservoir management practices.

Integrated reservoir management is a continuous process and the key to successful operation of the reservoir throughout its entire life. It requires the use of both multi-disciplines and technological resources for maximizing profit. A comprehensive reservoir management plan involves depletion and development strategies, data acquisition and analyses, geological and numerical model studies, production and reserves forecasts, knowledge of facilities requirement and economic optimization. These can facilitate better reservoir management which will enhance economic recovery of hydrocarbons (Satter et al., 1994). Intelligent well completion forms part of the overall vision of reservoir management optimization.

An intelligent well completion (IWC) is completion system capable of measuring, transmitting and analyzing wellbore production, reservoir and completion integrity data, and enabling remote action; change valve chokes and optimize these parameters to better control reservoir, well and production processes (Eni, 2006 ). The concept of intelligent completion does not generally refer to any capability for automated self-control but rather manual interface to initiate instructions to the well (Robinson, 2007).

Reservoir parameters are continuously monitored for each zones with permanent pressure and temperature gauges, base on which the valve chokes are reconfigured to allow simultaneous production from more zones through a single string or well. Remote completion monitoring is the ability of a system to provide data, obtained in or near the wellbore, without requiring access and entry for conventional intervention to the well. Hence IWC technology provides great flexibility in the operation of conventional wells and multilateral wells; as each branch of the well can be controlled independently. (Yeten et al., 2004)

The basic element of IWC are acquisition and transmission system, flow control valves (FCV) and actuation system. The acquisition and transmission system is a set of equipment used to transmit and acquire reservoir data, while the FCVs control flow rate from a zone or in a level. And the actuation system is a set of equipment that supplies power to the valves (Eni, 2006)

Compared to conventional completions, IWC offers great benefits. The primary objectives of IWC are normally to maximize or optimize and anticipate oil recovery, control gas and water breakthrough, reduce cost and improve safety. Zero intervention especially subsea or remote location wells and production optimization for multi zones reservoir (simultaneous production), horizontal wells, complex reservoir structure, auto gas lift, etc. justifies the installation of intelligent completions (Eni, 2006).