Network simulation for formation impairment due to suspended particles in injected water

• A new network model is built for simulation of particle deposition and its consequent formation damage.
• Force analysis for each particle is conducted and a new capture criterion for particles is proposed.
• Simulations for various factors are carried out and results are consistent with experiment results done before.
• Effect of pre-filtration is simulated.

A network model is developed to simulate the formation impairment process due to the capture of suspended particles in injected water, in which two paramount capture mechanisms—size exclusion and direct deposition—are taken into account. Based on the force analysis of each particle, an alternative capture criterion for direct deposition is proposed and incorporated into this model. The sensitivities for different factors are analyzed, such as the particle concentration in injected water, the pressure gradient placed on the network, the particle and pore–throat size distribution, and the fluid viscosity. The results exhibit very good agreement when compared with previous experimental data, which proves that this network model can be successfully used to reproduce the basic physical essence of the decrease in permeability and is efficient for studying the effect of different factors on the fine migration and its consequent formation damage. Furthermore, simulations are also conducted using the conditions under which the injected water is filtered before being injected into the network, which indicates that the pre-filtration process provides an effective tool for lowering or decaying the formation impairment.