Experimental Evaluation of Low-Carbon Cement and Its Application to the Oil and Gas Industry

Abstract

Summary This study initiates a series of tests to examine the application of Type IL cement for well-cementing operations. Type IL cement is a blend of 5–15% limestone with Type I/II Portland cement. This substitution by reducing the amount of CO2 emitted from cement plants can be aligned with sustainability efforts in the cement industry. We first measured the properties of cement slurry made of Type IL cement and compared them with specifications for the well cementing. The properties of hardened cement including the compressive strength and bonding strength were also examined. For compressive strength measurement, both cubic and cylindrical samples were prepared. To measure the bonding strength, the modified pushout test was used. We also investigated the effect of severe environments on the strength reduction of the hardened cement. In addition, the scaled abandonment plugging setup was used to quantify the sealing capabilities of Type IL cement in a well-plugging scenario. To force nitrogen flow through, differential pressure was applied to the system by decreasing the pressure above the plug-in controlled timesteps. We found that Type IL hardened cement offers substantial sealing capabilities compared with data available in the literature, although the leakage rate seems to gradually increase with each increase in differential pressure.