Real-Time Monitoring of Cement Hydration to Verify TOC and Well Integrity

Elisabeth Csar

Research output: ThesisMaster's Thesis

139 Downloads (Pure)

Abstract

Primary cementing is critical to zonal isolation and well integrity. Besides, cement plugs are used for several operations in the oil and gas industry, such as lost circulation control, formation testing, directional/sidetrack drilling, zonal isolation, and well abandonment. Set cement may be too soft or not in the planned location and hence fail to provide hydraulic seal and lead to well integrity and safety issues. This could be due to a number of issues, including contamination with wellbore fluids, ineffective displacement, and casing eccentricity. This thesis focuses on continuous monitoring real-time data during the hydration process of cement to be able to determine the phase of hydration process, to define the exact location of the cement, to establish contaminated parts of cement and prove a competent/imperfect well barrier. Electrical conductivity measurements could be an indication of how the cement slurry is hydrating and the degree of contamination. Several tests with different levels of mud contamination were performed and analyzed. In addition, experiments with fiber-optic sensoring to measure strain and temperature changes during cement slurry hydration were conducted. Both the electrical conductivity and fiber-optic measurements are able to identify degree of hydration and also level of contamination. The lab setup, test procedure, data, analysis, and results are presented and discussed. These measurements, analysis, and application would significantly improve the accuracy of cement jobs, and operational performance in the oil and gas industry. Benefits to the industry from continuous monitoring and evaluation are discussed. In addition, recommendations for future work and conclusions can be found in the last chapter of the thesis.
Translated title of the contributionEchtzeitüberwachung der Zementaushärtung zur Überprüfung des TOC und der Bohrlochintegrität
Original languageEnglish
QualificationDipl.-Ing.
Awarding Institution
  • Montanuniversität
Supervisors/Advisors
  • Ravi, Krishna, Supervisor (internal)
Award date25 Oct 2019
Publication statusPublished - 2019

Bibliographical note

embargoed until null

Keywords

  • Contaminated cement plug
  • Well integrity
  • Continuous monitoring
  • Fiber-optic sensoring
  • Conductivity measurment

Cite this