Innovative Fluid Migration Control Cement System Demonstrating Improved Results for Primary Cementing using Controlled Particle Size Distribution: A Novel Approach to Ascertain the Wellbore Integrity
Authors: Ali Wajid , Hashmi Ahmad Atef , Abdullah Al Turki Faisal , Bouaraki Mouloud , Aljardan Moaathe 
Published: February 2025

Abstract
Fluid migration after cementing is a well-known challenge in the oil and gas industry. Failure to prevent fluid migration is costly, extremely difficult to remediate, and more importantly, may lead to safety and environmental issues. This paper will review several case studies for deploying an engineered fluid migration control cement system as an important solution for primary cementing operations in case study wells with the risk of fluid migration.
Fluid migration has been of the utmost attention to oil and gas operating companies, as costly remedial cementing operations are needed to repair the deficiency in wellbore integrity caused by the formation fluid’s influx. After thoroughly reviewing the current practice of latex-based designs, the study identified a few limitations that persuaded the improvement of the cementing designs. Latex was replaced with three solid materials to provide lower permeability while maintaining the required compressive strength and fluid loss. This paper also illustrates the case studies where the innovative cement system was successfully applied to improve zonal isolation.
Cementing is a critical process that facilitates adequate zonal isolation for the lifetime of the well by placing cement slurry between the drilled formation and casing. The cement slurry system must be engineered to meet industry acceptance criteria, such as short transition time, low fluid loss, zero free water, and appropriate slurry density to prevent fluid migration. Latex-based slurry systems have been used to achieve these requirements. However, these systems are less effective at low downhole temperatures and generally exhibit delays in compressive strength development, which incurs additional costs to operating companies. To overcome these challenges, an engineered cement slurry system comprising a solid polymer, permeability reducer, and bonding enhancer was developed to offset shallow and deep hazards. As a result, the cement inside the shoe track was found to take more weight on the bit and had a slower penetration rate during drill-out, which confirmed early compressive strength development. Also, the sustained casing pressure occurrences were significantly reduced, even in areas historically prone to high severity of fluid migration through the cement slurry to the surface. This confirmed the effectiveness of this innovative solution.
This paper presents a detailed overview of the design of the novel fluid migration control slurry system to confirm its reliability and cost-effectiveness compared to a conventional latex-based slurry system. In addition, this paper demonstrates the case studies where this engineered solution was successfully deployed for the primary cement jobs to eliminate or mitigate the occurrences of sustained casing pressure with observed improvement in field deployment results.