Permeability decline due to flow of dilute suspensions through porous media

Suspension flow in porous media is encountered in many industrial applications. In the oil industry, suspended solids present in injected waters cart cause significant damage around the wellbore or deep in the formation. Depending on tire physical properties of tire solid particles, the porous medium, and operating conditions, solids can form external or internal filter cake, or just flow through the media without causing any damage. External filter cake formation causes a fast and sharp drop in permeability or injectivity of the formation. Reversing the flow direction can recover some of the damaged permeability. Internal filter cake formation cases a gradual or steady drop in permeability. Reversing the flow direction will not recover tire damaged permeability. Increasing solids concentration or particle size will cause more damage to formation. Injection of low-salinity water into sandstone reservoirs can trigger fines migration and clay swelling. Both factors can damage the formation. Injection of water that is incompatible with the formation brine may cause precipitation of insoluble sulfates that cart plug the formation. Stimulation (or acidizing) the formation cart also produce solid particles that can damage the formation. Corrosion by-products (e.g., iron sulfide) cart block the flow paths and reduce the permeability of themore » formation. Many experimental and modeling studies to predict formation damage due to flow of suspensions in porous media are discussed in this chapter. Solids can be present in injected waters or be generated in the formation. More research is needed to predict flow of suspensions in porous media when solid particles invade and are generated in tire formation simultaneously. 71 refs., 19 figs.« less