Mathematical modeling of fines fixation in the sandstone cores soaked by MgO nanofluid

Formation damage in oil reservoirs as a result of fines migration is a major reason for productivity decline. Fines loosely attached to the pore surface are in the equilibrium with the pore fluids. These particles start to flow when the equilibrium state is disturbed which, may end up in permeability reduction in porous media. Different solutions have been suggested to prevent detachment of fines from surface such as acidizing, ionic clay stabilizer, polymers and etc. Nanofluids containing metal oxide nanoparticles show specific properties. They have various applications including catalysis, waste remediation, additives in refractory and paint products. Our previous published works showed that MgO nanoparticle could be used as the best adsorbent of the fines in s synthetic porous media. In this work, Unit Bed Element (UBE) model and material balance were proposed to describe the effect of nanoparticles presence on fines fixation. UBE model relates dimensionless parameters of surface forces to fines removal efficiency of porous media. Material balance modeling provides an estimation of effluent fines concentration based on the injected fluid flow rate. Also the main mechanism for this fixation has been studied by surface forces analysis. Results show that soaking the core for 24 hours with 0.1% wt MgO nanofluid and water injection with 800 cc /hour could fix the fines which could used in particles release rate calculation in porous media. UBE and material balance modeling showed that the experimental results are trustable.