Micromodel Chip Application on a Kuwaiti Reservoir for EOR Processes Screening and Fluid Interaction Visualization

Micromodel chip is a fast, disruptive and cost-effective technology to dynamically assess the fluid-fluid interaction of IOR/EOR chemicals with reservoir fluids during displacement processes in porous media including screening. This technology captures images from the interactions between chemicals and hydrocarbons during flooding processes. Microfluidic experiments use a porous system made of silicon for assessing the fluid-fluid interaction of EOR processes. Key advantages are speed, low consummation of reservoir fluids and visual access to better understand the processes. In addition, image analysis algorithms allow to exactly determine important features such as recovery factor per whole model, per layer, or per any user-defined segment of such chip.

The main objective here has been to test micromodel chip technology and its potential to optimize/leverage future integrated EOR studies involving lab work prior to core-flooding. This was carried out on one of potential Kuwait sandstone reservoir candidate for Chemical EOR application.

An existing experimental set-up, including a 6x2 cm micromodel comprising a ‘high’ permeability (6,240 mD) and a ‘low’ permeability (1,350 mD), has been used to achieve the said objective. A work flow consisting of micromodel and fluid selection, waterflooding benchmark, and EOR flooding experiments, has been adopted. Three microfluidic flooding experiments showcase the potential of microfluidics for assessing chemical EOR processes and accelerating conventional laboratory EOR screening procedures.

The obtained results show significant incremental oil recovery improvement. Injection of the ASP chemical in secondary injection mode yields a 25.7% higher oil recovery factor (RF) at two (2) PV compared to waterflooding at (2) PV injected (40.0% versus 65.7% Injection of the ASP chemical in tertiary mode yields an ultimate RF of 76.2% compared to 77.9% in secondary mode. However, the Resistance Factor when injecting in tertiary mode is only 2.3 compared to 4.8 in secondary mode. This indicates better injectivity when ASP is injected in tertiary mode). It was also observed that the emulsification between the ASP chemical and oil, as well as between the ASP and brine can be clearly observed during the flooding experiments.

The tested ASP recipe has been confirmed as suitable to increase recovery in both low and high permeability layers. The emulsification between the ASP chemicals, oil, and brine has been clearly observed. All in all it can be concluded that micromodel chip technology is proved as a valuable tool in screening and evaluating EOR processes as it offers better speed, visualization, comparability, cost, and environmental impact.