Numerical Simulation and Field Application of a New Amphiphilic Polymer Activator for Heavy Oil Development

Abstract To effectively enhanced the recovery of the heavy oil with apparent viscosity greater than 150 mPa·s, a new amphiphilic polymer activator was designed. It is capable of simultaneously increasing water phase viscosity while reducing oil phase viscosity, which has been validate through massive physical experiments. However, the lack of effective simulation method restricts the promotion of large field application. In this paper, the oil displacement mechanism of the activator was evaluated through physical experiments including contact angle test and coreflooding experiments. The coreflooding experiments were carried out by using the flat homogeneous core model and the three-layer heterogeneous core model. A multi-component numerical simulation model of activator flooding was established using CMG. A numerical simulation inversion process based on the coreflooding data was proposed. Moreover, a comprehensive performance analysis was conducted for the field trial. The results indicate that the contact angle between the activator and the rock surface is 27° in the rock-oil-water three-phase system. The activator core flooding experiments show that the recovery rates were enhanced by 25.1% and 14.5% for three-layer heterogeneous cores and flat-plate homogeneous cores. The relative permeability curves of activator flooding for different models were obtained. The fitting accuracy calculated by CMOST reaches 92.7% in average. The enlarged field trial of the activator flooding in S oilfield effectively improved the uneven water injection profile and had little impact on the overall injection capacity. The average water injection index decreased by 16.4%. The average resistance coefficient of activator injector is 1.4. Although influenced by thief zone along P1-I3-P2 flow path, a decent field development performance with an incremental oil production of 5.5×104 m3 was achieved after the treatment of thief zone. The numerical simulation method proposed in this paper provides technical support for the scheme design of large-scale application of activator flooding. The comprehensive analysis of the field trial provides valuable insights for future full field implementation.