Visualisation Of Miscible Displacement Under Gravity Domination
Petroleum Engineering Honours Degree, 2011
University of Adelaide
Miscible displacement is a crucial part of Enhanced Oil Recovery (EOR) designed to exploit previously unrecoverable oil located in the reservoir. The importance of modelling CO2 on a pore level basis arises due to the limitations of conventional reservoir simulators. These simulators typically model two phase fluid flow on a macro scale comprised of many complex flow assumptions. Assumptions which were unable to account for factors such as, viscous fingering and interfacial instability on a pore. The solution to this problem lies with visualisation process utilising a glass micro model. Factors which previously could not be modelled can be accomplished utilising the proposed micro model approach.
The initial apparatus provided was designed specifically for the displacement of water dyed with Methyl Blue by CO2. This experimental procedure and apparatus designed for miscible displacement of water by CO2 could not meet the required conditions to satisfy miscibility, subsequently bubbles were presented during the visualisation process. The experiment changed from generating results into development of a method to replicate CO2 using a liquid- liquid approach. Selected fluids were Isooctane and Pentane to displace Butanol, which have similar mobility and density ratio to that of CO2 in the reservoir. Continual advances in methodology enabled successful visualisation results with changing viscosity, density and gravitational effects. The visualisation process generated results which showed the effects of injection rate on the fluid front and pore volume versus saturation graphs were generated.