An investigation into co2brinecementreservoir rock interactions for wellbore integrity in co2 geological storage

An investigation into co2brinecementreservoir rock interactions for wellbore integrity in co2 geological storage

Carbon dioxide

Oil wells

Gas emissions

Petroleum reservoir engineering

Boreholes

Oil field equipment

Scanning electron microscopy

Petroleum reservoirs

Aquifers

Hydrogeology

Rocks

Mechanical permeability

Porosity

Computerized tomography

Petrophysics

Inductively coupled plasma

Cements

Geological storage of CO2 in saline aquifers and depleted oil and gas reservoirs can help mitigate CO2 emissions. However, CO2 leakage over a long storage period represents a potential concern. Therefore, it is critical to establish a good understanding of the interactions between CO2brine and cementcaprock/reservoir rock to ascertain the potential for CO2 leakage. Accordingly, in this work, we prepared a unique set of composite samples to resemble the cementreservoir rock inter-face. A series of experiments simulating deep wellbore environments were performed to investigate changes in chemical, physical, mechanical, and petrophysical properties of the composite samples. Here, we present the characterisation of composite core samples, including porosity, permeability, and mechanical properties, determined before and after longterm exposure to CO2rich brine. Some of the composite samples were further analysed by Xray microcomputed tomography (Xray CT), Xray diffraction (XRD), and scanning electron microscopyenergydispersive Xray (SEMEDX). Moreover, the variation of ions concentration in brine at different timescales was studied by per-forming inductively coupled plasma (ICP) analysis. Although no significant changes were observed in the porosity, permeability of the treated composite samples increased by an order of magnitude, due mainly to an increase in the permeability of the sandstone component of the composite samples, rather than the cement or the cement/sandstone interface. Mechanical properties, including Youngs modulus and Poissons ratio, were also reduced. 2021 by the authors. Licensee MDPI, Basel, Switzerland.

16

14

Energies

2021

Jahanbakhsh, Amir

Liu, Qi

Mosleh, Mojgan Hadi

Agrawal, Harshit

Farooqui, Nazia Mubeen

Buckman, Jim

Recasens, Montserrat

Marotovaler, Mercedes

Korre, Anna

Durucan, Sevket

journalArticle

19961073

10.3390/en14165033