A Novel Nanoparticle Retention Model in Porous Media for IOR & EOR Applications

Summary Recent developments based on nanotechnology have shown the immense potential of application in EOR & IOR operations, which is supported by successful results on the lab and field-scales. However, the poor understanding and the shortage of a robust framework for nanoparticle transport-and-retention modelling in porous media is a downside for its properly spread in the Ο &G industry. In this work, we propose a novel modelling framework that allows to represent jointly mechanical and chemical mechanisms for nanoparticle retention and remobilisation in porous media. This model is formulated under a phenomenological approach that considers a strong physical basis of these processes on the macroscale. Retention and remobilisation dynamics are modelled under a non-equilibrium approximation using an α-order kinetic which depends on equilibrium condition. The mathematical formulation was programmed using the open-source package Chebfun, as a function of dimensionless variables to make up-scaling to higher scales more feasible. The impact of dimensionless variables in nanoparticle transport and retention was studied by a sensibility analysis which allowed to identify their effect on nanoparticle transport and retention. In this sense, some simplifications are proposed for the model according to the dimensionless variables. In order to validate this framework and its implementation, a set of lab tests was designed and carried out using silica-nanoparticle-based nanofluid in sand packs. Some concentration jumps were used to catch its effect on nanoparticle retention and remobilisation. Experimental data show a good agreement with simulation data under each operation condition and parameter fitting. Additionally, the model is capable of predicting the profile of nanoparticle concentration and its evolution on time. Changes in that profile can be predicted if operating conditions change, allowing their optimisation. Finally, this modelling framework is implemented in the multi-physic and multi-component tool DFTmp Simulator to simulate specific EOR & IOR application on the field-scale. Using the fitting parameters obtained previously, an application of IOR is simulated considering a multiphase system and other phenomena simultaneously.