Determination of the composition and static characteristics of a water shutoff agent for the Kalamkas field

This study focuses on developing and optimizing the formulation of a water shutoff agent and evaluating its static properties for application in Kalamkas field conditions. The proposed composition consists of modified starch (MS), unsaturated amides (UAM), a gelling agent (Y1), and a crosslinking agent (TN), which undergo polymerization to form a robust three-dimensional gel matrix. The research includes an assessment of the influence of reagent ratios and crosslinker concentration on the gel's rheological properties and water shutoff capacity. Experimental results demonstrate that the optimal concentration of the primary reagents – modified starch and unsaturated amides – lies in the 3.5-4.5 % range. The optimal UAM/MS ratio lies between 0.7 and 2.0, ensuring a balance between the mechanical strength and elasticity of the gel structure. The crosslinking agent concentration significantly affects gelation and structural integrity. It has been established that concentrations ranging from 0.08% to 0.10% provide an optimal crosslinking degree, preventing excessive rigidity while maintaining high-pressure resistance. The final formulation, SG-k (Strong Gel Kalamkas), was developed considering technical and economic factors. The optimized composition ensures a high-viscosity gel with a gelation time of approximately 20 hours, making it suitable for in-situ applications in the Kalamkas field. The presented results confirm that optimizing the composition of the water shutoff agent significantly improves its properties, which is critically important for reducing water inflow and leveling the profile leveling of injectivity. The findings contribute to advancing water inflow control technologies by providing a reliable and cost-effective water shutoff solution. Keywords: profile leveling; water shutoff treatments; gelation; polymers; crosslinking.