Low Carbon Footprint and Cost-Effective Resin Consolidation Application in High Clay Formation: Case Study from a Brown Field in Malaysia

Abstract

Sand production has been one of the main challenges in Field T especially at the upper reservoirs, exacerbated by the rising water cut as the field matures. Various sand control techniques have been implemented to address this persistent issue. Most of the wells in the upper reservoirs were completed with conventional gravel pack (high-rate water pack) as the primary sand control and has shown high reliability in controlling the sand. However, gravel pack completion remains relatively expensive despite efforts in recent years to enhance operational efficiency and reduce the cost. Moreover, this method often resulted in high skin which has adversely impacted the well productivity not only during initial production but also throughout the entire lifespan of the well. To mitigate these challenges, resin consolidation emerged as a viable option during the sand control evaluation for a new development (Well A) as primary sand control. Although development of resin has improved over time, the application remains a challenge especially for high clay content formation as the clays might impact the coating efficiency of resin and could lead to formation damage due to pore throat blocking. Fortunately, there are various established guidelines available based on actual implementation to ensure greater chance of success. During a drilling campaign in 2021, Well A encountered additional sand in the upper section which required sand control due to the unconsolidated nature of its formation. Resin consolidation was selected as the primary sand control for this well, primarily due to its cost-effectiveness compared to conventional gravel pack. Implementing resin consolidation in Well A via bullheading technique instead of gravel pack via workover enabled earlier production from the upper sands at a relatively lower cost. Historically, resin sand consolidation was successfully applied as primary sand control in nearby fields (Hasmin, et al. 2022). The treatment involves an injection of chemical into the near wellbore area with the aim to improve the strength of the incompetent formation, thus reducing the tendency of sand production. The main highlight of the resin application in Well A include achieving a low carbon footprint and cost-effective operation through bullheading technique which required less equipment compared to Coiled Tubing Unit (CTU) deployment. Additionally, these benefits were also realised by leveraging existing facilities during unloading operations, eliminating the need for additional equipment and further enhancing environmental and economic efficiencies. The critical design parameters contributed to the treatment's success include ensuring efficient chemical placement into formation through a combination of optimised well design & improved job procedures. This involved installing a nipple-less plug and junk catcher positioned 20 feet below the Sliding Side Door (SSD) prior to chemical pumping, limited entry perforation ( ~10 ft) with 4 shots per foot (SPF) 10/350-degree phasing configuration and placing the isolation packer near the perforation interval during the design stage. All these enhanced design parameters were implemented to ensure this well met the criteria for resin consolidation application. Laboratory analysis using representative cores played a crucial role in determining the optimal chemical formulation where the result showed that the samples achieved over 70 per cent retained permeability and a post Unconfined Compressive Strength (UCS) exceeding 1200 psi. Additionally, the application of mud acid i.e. 15 per cent Hydrochloric acid (HCl): 1.5 per cent Hydrofluoric acid (HF) prior to main treatment was also included in the treatment design and showed improvement on injectivity prior to the resin treatment. This practice was replicated from previous successful resin treatment (Hasmin, et al. 2022). This paper highlights the candidate qualification, laboratory analysis, treatment design, execution, challenges as well as best practices and lessons learnt during the implementation of the resin consolidation at Well A. This innovative approach not only could contribute towards reducing sand production issues in Field T while simultaneously achieving a lower carbon footprint and cost-effective operation. It also created opportunities for operators to consider implementing similar sand control methods in future development wells.