High Density Geopolymers: A Step Forward Towards Low Carbon Footprint Cementing Operations

Abstract

The utilization of ordinary Portland cement (OPC) in well cementing is accompanied by technical and environmental problems, leading researchers to explore alternative materials that address these issues and promote eco-friendliness. Geopolymer technology, widely used in construction and other industries, has not yet been fully implemented in oil and gas well cementing. Industrial waste materials, such as Class F fly ash (FFA), can be utilized to improve cement properties or create new cement binders. Hematite is used as a weighting agent to increase cement slurry density. However, heavy particle sedimentation in cement and geopolymer slurries is a significant issue that leads to heterogenous properties along the cemented section. This study introduces a new class of geopolymers that use both hematite and Micromax as weighting materials for high-density well cementing applications. One system only used hematite, while the other used both hematite and Micromax in an effort to eliminate sedimentation issues associated with hematite in geopolymers. The effects of adding Micromax on different FFA geopolymer properties were also evaluated. The study evaluated mixability, rheology, and pumpability to determine the mix design, which was then used to examine other properties such as strength, and density variation. The results showed that adding Micromax to hematite reduced the average density variation from 12.5% to 3.9%. Micromax addition also decreased plastic viscosity by 44.5% and fluid loss by 10.5%. Both systems performed closely in terms of strength.