Succesful Pilot Water Conformance Control Project at The X Field of The North Caspian Depression in Kazakhstan

Abstract Polymer used for water shut off (WSO) and conformance control (CC) is required to withstand both the temperature and salinity of the reservoir over prolonged timescales of months. For these reasons it is typical to find them as copolymers of acrylamide and acrylic acid, otherwise known as partially hydrolyzed polyacrylamides (HPAM).Selection of a polymer depends on more than the stability; it also depends on the application and desired effect. All lead to the final CC or WSO design.Type of application CC vs WSOLow MW vs high MW polymerChargeconcentrationPermeability and Homogeneity of the reservoirconcentration, topside viscosityDistance to the targeted treatment zoneconcentration of polymer, crosslinker, retarderHistory of the reservoirWell logs for streaks etc.production issuesconing or viscous fingeringWSO polymers tend to be lower molecular weight to be able to penetrate deeply into smaller pores. lower viscosity on topside facilities also allows higher concentrations. Down hole, these are able to then set up strong well held rigid gels that prevent water flow One of the best tools to identify the zones were WCC can give a better result is tracer test. Tracer applications in the oil industry began in the mid-20th century (Hutchins et al. 1991; Serres-Piole et al. 2011, 2012). Today, tracers and nanoparticles are integral to various oil and gas drilling and testing operations. These substances are introduced into borehole fluids to trace fluid pathways, migration mechanisms, and well connectivity. Tracers are extensively used in drilling, water flooding, and E&P stages to assess hydrocarbon migration, optimize flooding strategies, and estimate residual oil saturation (Sor) and enhanced oil recovery (EOR) (Bjornstad et al. 1990; Clayton 1967; Michael Shook et al. 2004; Michael Shook et al. 2017; Sun et al. 2021; Sun and Ertekin 2020). The X field is at a late stage of development of its only production target - the Valanginian horizon. The development of this horizon is envisaged with waterflooding. The reservoirs of the Valanginian horizon are mainly composed of 3 layers. Despite some differences in capacitive parameters, they are all hydrodynamically connected.