Effect of back pressure on the gel pack permeability in mature reservoir

Abstract

Excess water production has become a significant problem for oil field operations as reservoirs mature. In mature oilfields, gel treatments are using preformed particle gels (PPGs) to reduce fluid channels through super-high permeable formations. As a result, water production decline and sweep efficiency improve. The achievement of the best PPGs treatment mainly depends on whether or not PPGs can successfully reduce the permeability of the channels to the level that we expect. The objectives of this work are to determine what factors influence the blocking efficiency of PPG on fluid channels. It will determine what factors effecting on PPGs pack permeability. A transparent model was designed to observe the compression of gel particles in fluid channels at different back pressures, and thus to study the effect of different parameters on PPG blocking efficiency. PPG pack in the fluid channels affected by the back pressure. It was determined that the increase of the back pressure decreased the PPG pack permeability. Gel pack is compressed and its permeability is reduced as back pressure increases. A permeable gel pack was formed in fluid channels by gel particles. The permeability of the gel pack depended on particle strength, particle size, and back pressure. The results can be used to optimize a PPG design.