University of Alberta (Canada) researchers have designed a microfluidic chip which represents the pore structure of a naturally occurring oil-bearing reservoir rock and enables performing traditional waterflooding experiments in this “reservoir-on-a-chip” (ROC). Oil exploration companies could use ROC technology to determine what concentration of water and chemicals they’ll need to use to maximize oil recovery.
Mechanical engineering professor Sushanta Mitra led a research team that uses core samples from oil drilling sites to make 3-D mathematical models of the porous rock formations of oil reservoirs.
The pore-network has been etched in a silicon substrate and bonded with a glass covering layer to make a complete microfluidic chip, which is termed as ‘Reservoir-on-a-chip’ (ROC)...Oil is kept as the resident phase in the ROC, and waterflooding is performed to displace the oil phase from the network. The flow visualization provides specific information about the presence of the trapped oil phase and the movement of the oil/water interface/meniscus in the network. The recovery curve is extracted based on the measured volume of oil at the outlet of the ROC.
We also provide the first indication that this oil-recovery trend realized at chip-level can be correlated to the flooding experiments related to actual reservoir cores. Hence, we have successfully demonstrated that the conceptualized ‘Reservoir-on-a-Chip’ has the features of a realistic pore-network and in principle is able to perform the necessary flooding experiments that are routinely done in reservoir engineering.—Gunda et al.
|Reservoir-on-a-chip. Click to enlarge.|
The findings were published in the RSC journal Lab Chip.
Naga Siva Kumar Gunda, Bijoyendra Bera, Nikolaos K. Karadimitriou, Sushanta K. Mitra and S. Majid Hassanizadeh (2011) Reservoir-on-a-Chip (ROC): A new paradigm in reservoir engineering. Lab Chip, 11, 3785-3792 DOI: 10.1039/C1LC20556K