JPT Study Investigates Formation Damage Induced by Water Reinjection in Unconsolidated Sands

SPE.org 

The authors performed a complete experimental laboratory study using suspensions containing solid particles, mono-sized oil droplets, or both. Several coreflooding experiments using highly permeable sandpacks were performed over a long duration, during which significant volumes, sometimes reaching 100 L, have been injected. Also, permeability evolution has been monitored along three sections of each sandpack in order to better understand the dynamic of associated formation damage. A schematic of the experimental setup used to carry out the coreflooding experiments is shown in Figure 1. The suspensions containing solid particles or oil droplets were previously prepared in a 70-L reservoir tank. The tank is made from glass to facilitate suspension stirring and to prevent the aggregation of solid particles within it. The tank’s volume allows an injection over days and nights without interruption. The injection of suspension is ensured by a pump equipped with two low-diameter section pistons to ensure a proper injection of suspension without sedimentation of solid particles.