Evaluation of cement integrity using distributed temperature sensing - PowerPoint PPT Presentation

Evaluation of cement integrity using distributed temperature sensing Jan Henninges and Wulf Brandt ENGINE Workshop 4, Drilling cost effectiveness and feasibility of high- temperature drilling, Reykjavik, Iceland, July 2-5, 2007 Dr. J. Henninges, ENGINE Workshop 4, Reykjavik, Iceland, July 2-5, 2007.

Overview Motivation: • Cementing: important operation, difficult to control • Primary objectives: support casing, seal annulus • Questions: how much cement in place? „Quality“? Methods: • Temperature – heat of hydration during setting of cement • Acoustic – attenuation, mechanical coupling • Nuclear – admixture to cement slurry Case study: • Permanent monitoring of CO 2 injection and storage (CO2SINK) • Behind casing sensors: monitoring during operation • Fiber-optic distributed temperature sensing (DTS) during cementing Dr. J. Henninges, ENGINE Workshop 4, Reykjavik, Iceland, July 2-5, 2007.

Well design VERA DTS • 18- 5/8“ surface casing (cemented) 18-5/8” • 9- 5/8“ intermediate casing (cemented) • 5- 1/2“ casing: – 8- 1/2“ hole – two 9m filter screen sections – permanent sensor cables behind casing 9-5/8” – DTS: fiber-optic distributed temperature sensing cable – VERA: vertical electrical resistivity array • stinger cementation Filter #1 – below filter screens 5-1/2” Filter #2 – 2,2 m³ of API Class G cement Dr. J. Henninges, ENGINE Workshop 4, Reykjavik, Iceland, July 2-5, 2007.

Installation of DTS and ERT cables in 1st well (May 5-6, 2007) Dr. J. Henninges, ENGINE Workshop 4, Reykjavik, Iceland, July 2-5, 2007.

DTS temperature profiles - pumping of cement Quaternary Tertiary Cretaceous Jurassic Upper Triassic Weser fm Stuttgart fm Grabfeld fm Dr. J. Henninges, ENGINE Workshop 4, Reykjavik, Iceland, July 2-5, 2007.

DTS temperature profiles - setting of cement and circulation Quaternary Tertiary Cretaceous Jurassic Upper Triassic Weser fm Stuttgart fm Grabfeld fm Dr. J. Henninges, ENGINE Workshop 4, Reykjavik, Iceland, July 2-5, 2007.

3D-view of DTS temperature data during cementing pumping of cement fluid circulation over filter screens setting of cement cement head 2nd filter 1st filter Dr. J. Henninges, ENGINE Workshop 4, Reykjavik, Iceland, July 2-5, 2007.

Change of temperature with time 60 55 50 Temperature (°C) 45 40 Filter 1 top 35 Filter 1 bottom Filter 2 top 30 Filter 2 bottom Cement 744-754m 25 Cement 754-776m Cement 776-792m 20 07.05. 07.05. 07.05. 08.05. 08.05. 08.05. 08.05. 09.05. 09.05. 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 Date and Time Dr. J. Henninges, ENGINE Workshop 4, Reykjavik, Iceland, July 2-5, 2007.

Temperature profiles – initial condition Dr. J. Henninges, ENGINE Workshop 4, Reykjavik, Iceland, July 2-5, 2007.

Temperature profiles – pumping of cement Dr. J. Henninges, ENGINE Workshop 4, Reykjavik, Iceland, July 2-5, 2007.

Temperature profiles - pumping of cement flow over lower filter Dr. J. Henninges, ENGINE Workshop 4, Reykjavik, Iceland, July 2-5, 2007.

Change of temperature with time and hydraulic data 45 500 P/Q data shifted -5 min.! 450 40 400 Pressure (bar) / Flowrate (l/min) 350 Temperature (°C) 35 300 Filter 1 top 250 Filter 1 bottom 30 200 Filter 2 top Filter 2 bottom 150 Cement 744-754m Cement 754-776m 25 100 Cement 776-792m Pressure (bar) 50 Flowrate (l/min) 20 0 07.05. 11:30 07.05. 11:45 07.05. 12:00 07.05. 12:15 07.05. 12:30 Date and Time Dr. J. Henninges, ENGINE Workshop 4, Reykjavik, Iceland, July 2-5, 2007.

Temperature profiles – circulation of KCl pill Dr. J. Henninges, ENGINE Workshop 4, Reykjavik, Iceland, July 2-5, 2007.

Temperature profiles – setting of cement cement head cement inside casing? Dr. J. Henninges, ENGINE Workshop 4, Reykjavik, Iceland, July 2-5, 2007.

Temperature profiles and cement bond log VERA DTS 18-5/8” 9-5/8” Filter #1 5-1/2” Filter #2 Dr. J. Henninges, ENGINE Workshop 4, Reykjavik, Iceland, July 2-5, 2007.

Summary and Outlook • Successful installation of permanent sensor cables behind casing • Continuous temperature monitoring: Location of cement head Amount of cement in place On-line information during operation • Evaluation of sealing, zonal isolation: other methods (CBL, etc.) • Advanced thermal modeling: thickness of cement sheath? Dr. J. Henninges, ENGINE Workshop 4, Reykjavik, Iceland, July 2-5, 2007.