The presence of residual oil or gas during fines migration in porous media greatly affects particle mobilization and capture. This paper investigates the effects of kaolinite content on fines migration and formation damage in the presence of oil residual. We carried out corefloods on engineered sand-packs that contained different percentages of kaolinite. Each core sample was subjected to brine injections varying from seawater salinity to freshwater. Measurements of the pressure drop and effluent particle size distributions were performed for each injection. It was determined that the main cause of permeability decline was pore throat straining by kaolinite. A higher decline of permeability accompanied by intensive fines production was encountered during freshwater injection. If compared with fines migration under single-phase flow, having a residual phase showed a significant decrease in formation damage and the amount of produced kaolinite. The laboratory data were matched with the analytical model for one-dimensional linear flow. A close agreement between the coreflood data and the model was obtained. The model coefficients were used for well injectivity decline prediction using a numerical one-dimensional radial injection model. The kaolinite content and the residual oil phase greatly impacted the well injectivity decline.

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With most polymers employed in polymer enhanced oil recovery exhibiting one or both non-Newtonian behaviours that is shear thickening and thinning at different shear rate, it is expedient to analyse the impact of these non-Newtonian behaviours in polymer optimisation. CMG simulation suite was employed to analyse the permeability pinch-out formation with a five (5) spot injection well pattern for a 360days simulation run using a 90days polymer injection well cycling. Shear thinning polymer was found not to be conducive for lower permeable formation as a high percentage of the polymer was retained. NPV was affected by polymer injection rate which controlled polymer optimisation

Tight oil accumulates in impermeable reservoir rocks, often shale or tight sandstones. The flow behaviour of tight oil in unconventional reservoirs is described by peculiar complexities such as the typical low permeability to viscosity ratio and the dissolution of some gases in the oil phase. Reservoir simulations that consider these complexities negligible stand the potential of poorly characterizing the reservoir flow dynamics. The adoption of similarity transformation effectively reduces the complexities associated with the flow equations through spatial variable (r) and temporal variable (t). The Boltzmann variable $$\left(\xi =\dfrac{r}{\sqrt{t}}\right)$$ ξ = r t is introduced to facilitate the reformulation of transient two-phase flow phenomenon in a radial geometry. The technique converts the two-phase Black oil model (thus highly nonlinear partial differential equations (PDEs)) to ordinary differential equations (ODEs). The resulting ODEs present a reduced form on the flow model which is solved by finite difference approximations (the Implicit-Pressure-Explicit-Saturation (IMPES)) scheme. No loss of vital flow characteristics was observed between the Black oil model and the similarity transform flow model. Furthermore, the similarity approach facilitated the determination of pressure and saturation equations as unique functions of the Boltzmann variable. This derivation is applied to an infinitely acting reservoir where the Boltzmann variable tends to infinity ($$\xi \rightarrow \infty$$ ξ → ∞ ). Finally, this case study’s analytical solution formulated critical relations for fluid flow rate and cumulative production, which are useful for single-phase flow analysis.