Gas Breakthrough Detection and Production Monitoring From ICD Screen Completion on Lukoil's Korchagina Field Using Permanently Installed Distributed Temperature Sensors

Abstract

Lukoil-Nizhnevolzhskneft is developing its Korchagina oil field in the Russian sector of the Caspian Sea using inflow control device (ICD) sand screen completions producing from horizontal wells. The ICD completion is used to delay gas and water breakthrough and extend the well's production life. Offshore operations, restricted wellhead access and a relatively low TVD limit conventional production logging possibilities, so Lukoil has chosen to install permanent fiber-optic distributedtemperature monitoring systems with its sand screens and to use these systems to monitor and optimize production.The optical fiber has been deployed on the outer part of the sand screen shroud in this horizontal, low-drawdown well. Installing the fiber outside the ICD sand screens gives a unique direct measurement of the inflow temperature from individual well zones (the effect of Joule-Thomson warming/cooling of the flowing fluids caused by the pressure drawdown), excluding the effects of thermal mixing of the reservoir fluid flowing inside the wire-wrapped screens. This inflow temperature responds directly to zone drawdown and fluid Joule-Thomson properties, allowing these properties to be monitored over time.Descriptions are provided of the completion technology used to install the fibers along the ICD sand screens and of the data and results obtained. Thermal models of the near-well environment are also described and are used to analyze the data for early detection of the gas breakthrough and to allow real-time production optimization. The installed optical fiber proved its value for production optimization in this ICD completion in the Korchagina oil field.

The Results of the Pilot Works on Well Completion Technologies and Continuous Monitoring on the Example of Extremely Long Horizontal Wells of the Yu. Korchagin Field in the Caspian Sea

“…Thus, it was decided to carry out pilot works on monitoring horizontal wells using fiber-optic temperature measurement systems (Chertenkov, 2012). This approach is one of the possible solutions to ensure continuous monitoring of the inflow profile in the wellbore and is a method that does not require intervention in the well during its operation.…”