Non-Invasive Remedial Chemical Sand Control Solution for Damage-Free Reservoir Management

Abstract The surge in sand production in oil and gas fields poses significant financial challenges, leading to premature equipment deterioration and wellbore sand buildup. Combating this issue involves a blend of chemical and mechanical interventions. While some conditions favour chemical solutions, others require a combined approach. This paper focuses on introducing a non-invasive sand agglomeration technique for sand and fines control. Drawing insights from a pilot project in Northern Sabah Field, Malaysia, it covers essential testing procedures to comprehensively evaluate treatment effectiveness. A thorough exploration of chemical performance in downhole conditions was undertaken through a structured five-stage process. In the initial Reservoir Parameters Testing, XRD/XRF, LPSA, and SEM analyses were applied to scrutinize sample conditions, with subsequent repetition of LPSA and SEM analyses for treated samples. Chemical Thermal Stability Testing followed, assessing the chemicals' thermal stability. The third stage, Chemical Compatibility Testing, focused on the interaction of chemicals with other downhole components. Preliminary Testing, the fourth stage, utilized Bottle Test and Flow Test to determine optimal chemical concentration. The fifth stage, Core Flooding, assessed return permeability and critical velocity, providing conclusive evidence of the chemical treatment's effectiveness on sand agglomeration. In this study, we utilized a sample from Field B, with particle sizes ranging from 10μm to 1020μm and a clay content of 16%. Throughout testing phases, we meticulously observed and recorded chemical performance and sample-chemical interactions. Chemical thermal stability and compatibility tests unveiled variations in the chemical's physical properties, including emulsion and precipitate formation. Preliminary testing scrutinized the chemical-sand sample reaction, considering additional additives like pre-flush chemicals and shale inhibitors. Once the optimal outcome was determined, application testing analysed critical velocity and return permeability of the treated sample. However, not only was comprehensive laboratory testing insufficient, but also if the field application didn't align with the lab testing. A hard-earned lesson from the pilot field application indicated that the root cause of the sand agglomeration application failure was mainly due to a mismatch in the screen size used during laboratory testing and field application. Hence, the pilot field application provided valuable insight to increase the success rate of sand agglomeration application. Sand agglomeration presents itself as a supplementary approach to primary and secondary sand control methods, particularly in instances where conventional sand screens or gravel packs prove ineffective in containing sand production. Moreover, introducing the sand agglomeration chemical into the formation is non-detrimental to permeability and preserves the desired production rate. As a result, this sand control technique provides operators with cost-effective remedial solutions and production advantages.