PSI - Issue 64

Michael Iten et al. / Procedia Structural Integrity 64 (2024) 1642–1648 Iten et al. / Structural Integrity Procedia 00 (2019) 000 – 000

1648

7

5. Conclusions The continuous temperature data acquired during cementation of the casings showcases the ability of DTS systems to track small temperature changes in near real-time. During the cementation process, the displacement of the drilling fluid (see Fig. 3 and Fig. 4) and the setting of the cement (Fig. 5) were captured with distributed temperature measurements. The DTS data was valuable to estimate the depth and setting speed of two different cement compositions. In future, the monitoring system will be used to acquire spatiotemporal temperature data during stimulation treatments and operations of the seasonal geothermal energy storage. The authors believe that the experience made with this fiber-optic monitoring system can be transferred to other applications, such as geothermal energy or geological gas storage and in this context provide information for the caprock integrity analysis and risk assessment with the fiber-optic monitoring system providing temperature, strain and acoustic data from a single cable that requires minimal space. Aranzabal, N., Martos, J., Steger, H., Blum, P., Soret, J., 2019. Temperature measurements along a vertical borehole heat exchanger: A method comparison. Renewable Energy 143, 1247-1258. Dakin, J., Pratt, D., Bibby, G., Ross, J. , 1985. Distributed optical fiber Raman temperature sensor using a semiconductor light source and detector. Electron. Lett. 21, 569-570. EWB, 2023. Energie Wasser Bern, visited on 29.11.2023. Geospeicher: Wärme für den Winter speichern. https://www.ewb.ch/ueber uns/unternehmen/kraftwerke/geospeicher.php. Giuseffi, M., Ferdinand, P., Vrain, A., Philippe, M., Lesueur, H., 2010. Raman Distributed Temperature Sensing in underground GeoExchange System. Proceedings of SPIE. Karamehmedović, E., Glombitza, U., 2004. Fiber - Optic Distributed Temperature Sensing Using IOFDR, 2nd European Workshop on Optical Fibre Sensors, EWOFS´04, SPIE Vol. 5502, pp. 200-203, Santander, Spain. Kellerhals, P., Haefeli, C., Staeger, D., 2000. Bern (LK 1166): Erläuterungen von A. Isler, Geological Atlas of Switzerland, Federal Office for Water and Geology. Shiota, T., Wada, T. , 1991. Distributed temperature sensors for single mode fibers. Proc. SPIE 1586, 13 -18. Ukil, A ., Braendle, H., Krippner, P., 2012. Distributed Temperature Sensing: Review of Technology and Applications. IEEE Sens. J. 12, 885-892. Williams G., Brown G., Hawthorne W., Hartog A., Waite P., 2000. Distributed temperature sensing (DTS) to characterize the performance of producing oil wells, SPIE Industrial sensing systems Conf., Boston. References