Journal of Petroleum Technology, Vol.53, No.3, 51-52, 2001
Controlling gelation time and microgel size for water shutoff
Injecting stable preformed microgels as relative-permeability modifiers to reduce water production helps minimize the risk of formation plugging and, consequently, of inefficiency of in-depth treatments. The microgels formed in a diffusion regime are isotropic and their size decreases significantly as shear rate increases. Microgels formed in a correction regime are anisotropic and their size decreases negligibly with shear rate. Experimental data show that microgel preparation can be optimized for the planned application, either as relative-permeability modifiers for water shutoff or as viscosity enhancers for polymer flooding.