Introduction of a Low-Carbon Geopolymer Alternative for Sustainable Cementing Applications across the Middle East: A UAE Case Study

With the focus on sustainability in oilfield drilling operations, many initiatives are being implemented across the industry to lower carbon emissions and reduce the overall environmental footprint. One such initiative involves transitioning away from Portland cement in well construction and replacing it with a low-carbon alternative. Across the Middle East, an alternative geopolymer system has been successfully introduced, with case histories in Oman, the UAE, Saudi Arabia, and Qatar. This paper focuses on case histories from the UAE. Portland cement has been used as a well barrier in the oilfield for over 100 years. However, its manufacturing process is energy-intensive and results in significant CO2 emissions. By introducing an alternative solution, the CO2footprint can be substantially reduced while the properties of Portland cement can be matched or even improved. To facilitate the implementation of the geopolymer system, the job design and execution must remain similar to current cementing practices. Additionally, the liquid and set properties of the geopolymer system must be comparable to, or better than, the properties of the Portland cement systems currently used for each operation. The introduction of the low-carbon geopolymer system begins with identifying local sources of suitable aluminosilicates as the primary material. To minimize transport-related emissions, a local source was identified in each country. Extensive laboratory testing was performed to qualify the raw material and produce a fluid design that meets the requirements for wellbore conditions. Standard cementing lab equipment and procedures were used for laboratory testing. Additives were either dry-blended or added to the mix fluid, offering a wide variety of options to achieve the required fluid properties. Local yard testing demonstrated that the geopolymer system could be batch-mixed or fly-mixed as required by rig operations and local preferences. The bulk material is easy to handle and can be used on land or transported offshore as needed. Standard bulking and cementing equipment were used in the field. The geopolymer system has been successfully introduced for conductor and surface casing operations, as well as for remedial jobs such as top jobs. Job evaluation procedures, including post-job pressure matching and cement bond evaluation, are similar to those for regular cement jobs. Using case studies from the UAE, this paper presents the introduction of the low-carbon geopolymer system as an innovative and sustainable alternative to Portland cement. The planning, execution, and evaluation of these cement-free jobs demonstrate its application as a suitable alternative to Portland cement in oilfield operations.