Research on Profile Control and Water Shut-off Performance of Pre-crosslinked Gel Particles and Matching Relationship between Particle and Pore Size

Abstract

Experiments on injectivity and profile control performance of pre-crosslinked gel particles widely used in oilfields were done .The results show that, the injectivity of pre-crosslinked gel particle is poor Most of particles pile up in the front of sand pack, and the migration distance of pre-crosslinked gel particles is less than twenty centimeter, which lead to the formation of filter cake and the poor effects of depth profile control. The injection of pre-crosslinked gel particle is selectivity. In the early stage of profile control, the diversion rate of low permeability layer increases slightly. After long-term waterflooding, due to the easily breakthrough in higher permeability layers, the diversion rate of low permeability layer declines in comparison that before the operation. It is indicated that pre-crosslinked gel particles will harm low permeability layers. It is calculated and analyzed that the diameters of current pre-crosslinked gel particles are bigger than pore size. Theoretically, current pre-crosslinked gel particles are difficult to be applied in depth profile control.
Key words: pre-crosslinked gel particle; profile control and Water Shutoff; particles diameter; pore size