Dear DPS member,
Our December DPS meeting will be on December 7th (Thursday ) at our usual venue KIVI in Den Haag (Prinsessengracht 23, 2514 AP Den Haag) at Molkamer on the 1st floor.
Doors opening for pre-meeting coffees at 15:30 hand the meeting commencing at 16:00h.
After the meeting there will be our usual social with drinks at a local cafe.
Thanks to the generosity of our sponsors, attendance is free for members of the DPS.
We will host two presenters sharing their expertise
Talk 1: Safe, Long-Term Storage of CO2: How Geomechanics and Petrophysics Need to go Hand-in-Hand
Speaker: Suzanne Hangx, Assistant Professor, High Pressure and Temperature Laboratory, Department of Earth Sciences, Utrecht University
Abstract:
To curb global CO2 emissions, CCS (Carbon Capture and Storage) is considered to play a key role in meeting emission reduction targets. In the Netherlands, many potential storage locations can be found in (soon-to-be) depleted gas fields. However, injection of CO2 takes the reservoir-caprock-fault system out of its natural physical and chemical equilibrium, which may impact the long-term safety of the store. Notably the chemical reactions and interactions CO2 can have with the grain framework, and how this impacts rock strength and transport properties, are crucial. In this contribution, I would like to outline what we have learned about the relationship between geomechanics and petrophysics in the context of CO2 containment. I will conclude the presentation with a brief outline on how our learnings for CCS can help us to better pinpoint possible challenges for other subsurface usages, such as geothermal energy production and temporary hydrogen storage.
Speaker Bio:
Suzanne Hangx performed her PhD research at Utrecht University (2009) in the context of the Dutch national research programme CATO (CO2 Afvang Transport en Opslag). For her contribution to CO2 storage research, she received the Outstanding Young Scientist Award of the European Geosciences Union in the Energy, Resources and Environment Division. After finishing her PhD, she joined the Containment group at Shell Global Solutions in Rijswijk. Here she worked on the geomechanical assessment of pilot projects such as the UK Peterhead CCS project. In 2015, she returned to academia. These days, her research portfolio contains a range of sustainability-related topics, from CCS to geothermal energy production, hydrogen storage and radioactive waste storage.
Talk 2: What Controls Well Leakage in a Cement Sheath?
Speaker: Al Moghadam, Senior Geomechanics Specialist, Applied Geosciences Group, TNO
Abstract:
Portland cement is the most important sealing material used in wells. Cement is pumped in the well annulus to provide mechanical support for the casing and the wellbore, and to ensure zonal isolation. Cement undergoes hydration reactions and gradually transitions from a slurry phase to a poroelastic state. Some wells experience leak issues marked by sustained casing pressure and zonal communication. Cement Bond Logs (CBL) have been used to identify the presence of microannuli in wells. However, CBLs are only a snapshot in time and depend on the conditions of the well at the time of the measurement (e.g., the pressure in the casing). Improvement in centralization and cement additives have significantly enhanced cement jobs to avoid such failures. Inexplicably, some wells show debonding even with best cementing practices.
In this talk, we focus on the physics behind debonding of cement interfaces. We have conducted the first ever experiments to measure the stress evolution of a cement sheath under constant pressure and displacement boundary conditions. Our results show that cement stress drops significantly as it cures. This drop is a function of the water availability, the axial load, and the formation stiffness. The stress drop will not be uniform along the cement sheath. The operational pressure and temperature of a well can overcome the remaining cement stress and open a leakage pathway. We apply these lessons to a case study on a hydrogen storage well to estimate leakage for different operational scenarios.
These results explain why, even with best cementing practices, some sections of the cement sheath show poor bonds in CBLs. In addition, the results have important consequences for well abandonment practices and engineering assessment of wells. Accurate assessment of cement stress is critical in designing safe operating windows for CCS and hydrogen storage wells.
Speaker Bio:
Al Moghadam is a Senior Geomechanics Specialist at the Applied Geosciences Group of TNO. He holds a PhD in Geotechnical Engineering from University of Alberta, Canada with an undergraduate degree in reservoir engineering from Sharif University of Technology, in Iran. He has ten years of experience in various academic, research, and consulting positions in Canada and Europe. He specializes in geomechanical experiment design and numerical modelling, with a particular focus on well integrity assessment. Currently, he is the lead scientist in a number of projects spanning from small industry-led ventures to large consortiums related to well integrity and leakage. His work focuses on quantitative assessment of leakage in CCS, hydrogen, and abandoned wells.
We are looking forward to seeing you there,
DPS board