Monitoring of a reverse cement job in a high-temperature geothermal environment

Geothermal Energy

Sigurdur G. Bogason¹  Martin P. Lipus²  Thomas Reinsch²  Ari Stefánsson³  Tobias B. Weisenberger⁴  Steinar Kragset⁵ 

[1] GEORG Geothermal Research Cluster;GFZ German Research Centre for Geosciences;HS Orka hf;Iceland GeoSurvey (ÍSOR);NORCE Norwegian Research Centre AS;

关键词: Well cementing;    Well integrity;    Distributed temperature sensing (DTS);    Iceland deep drilling project (IDDP-2);   

DOI  :  10.1186/s40517-021-00187-y

来源: DOAJ

【 摘 要 】

Abstract Cementing operations in wellbores, especially for long casings, are often challenging and prone to deficiencies when not properly planned and executed. While exploring for and exploiting of geothermal resources at temperatures above the critical point of water was attempted in different drilling projects in recent years, the well design, and especially the procedure to run and cement long production casings became a key challenge for drilling engineers. For the first time, a reverse cementing job for a 2.97 km long production casing in a high-temperature geothermal well could be monitored and analyzed using a combination of permanently installed distributed fiber optic and electronic sensors as well as conventional well logging equipment. Data from the permanently installed sensors were used to monitor and evaluate the cementation process as well as the onset of the cement hydration. Based on the data, the understanding of downhole fluid dynamics during cementation could be improved. Our analysis suggests that the cement was diluted during cement placement and partly lost into the formation. These findings can help to better prepare for future drilling ventures under similar downhole conditions.

【 授权许可】

Unknown