Increase the Effectiveness of Water Shutoff Operation Using Acoustic Leak Detection and Pressure Thermal Log in Mature Field South Sumatera – Indonesia

Abstract

The evaluation of flow profile in the wellbore system is an important part of oil & gas field development. Leaks that occur in or behind the production casing is not only potentially causes safety and environmental issue but also potentially misjudgments of production performance analysis and the estimation of remaining reserve. The flow profile in the wellbore mostly affected by the life cycle of well during drilling phase, completion phase, production or injection phase and restoration phase. One of many well-known technologies applied in oil & gas industries is acoustic leak detection and pressure thermal log. The selection of surveillance technique to identify undesired water flow problem is not only provides more effective result but also carries an acceptable risk in term of the project cost. The objective of this paper is to show how a new approach of acoustic leak detection and pressure thermal surveillance can be used to increase the effectiveness of water shutoff operation in mature oil and gas field. The new approach of dynamic surveillance technique provided the acoustic, pressure and thermal data acquisition along the artificial lift wells can be interpreted. The case studies shows that the undesired water flow in or behind production casing can be identified precisely compared with a conventional method such as cement bond log. As the result, the data interpretation gives a remarkable result both of the successful water shutoff operation and post job production performance. Water significantly can be reduced from 1300 bbl per day to 320 bbl per day and the other hand oil & gas significantly can be increased from 34 boepd to 532 boepd. Moreover, this paper should be beneficial to help all petroleum engineers currently working in mature oilfield not only to identify undesired water flow problem precisely but also develop a comprehensive and effective water shutoff and remediation plan.