Re-Associated Polymer Particle Gels by In-Situ Nanosilica Gels for Water Shutoff Applications in Fractured Reservoirs

Abstract

Abstract Re-association of preformed particle gel via colloidal nanosilica is an innovative kind of preformed particle gel of which particles can bond together to form a reinforced bulk gel system after being placed in a fractured having unwanted water production. The objective is to minimize water production of the oil wells by treating the non-productive conductive paths, mainly referred to as reservoir heterogeneity having natural or induced fracture which is connected to water aquifer. The ultimate objective of this research is to evaluate the newly developed systems for water shutoff application in fractured reservoir, using different testing methodologies. Thermogravimetric Analysis (TGA) and dynamic mechanical analysis were conducted to benchmark performed particle gels swelled in water and nanosilica/activator. In addition, curing time (re-association) must be defined to allow safe pumping operation of the fluid through the tubular and into the target zone; therefore, the re-association (gelation time) of the particle gels were investigated. A coreflooding test was carried-out to evaluate the plugging efficiency of the newly developed technology using an induced fractured core plugs. TGA thermograms of polymer particle gels swellen in water and Nanosilica revealed that the semi-quantitative result indicated that the total weight losses (TWL) of the samples are approximately 47wt.% and 18 wt.%, respectively, while the residual masses are found to be approximately 53 wt.% and 82 wt.%, respectively. Furthermore, the results obtained from dynamic mechanical analysis, the storage modulus (G') was much higher with particle gels swelled in in-situ nanosilica than swelled in water, the newly developed composite gels behave more solid-like material. Additionally, the (re-association of the particle gels) curing time can be controlled by adjusting activator concentration from minutes to hours, which allows a predictable and controllable pumping time. The core flooding findings unveiled that this robust newly developed material efficiently plugged the facture core with high pressure of 2000 psi. Evolving technologies are required in the oil industry to overcome the existent challenges. Re-association of preformed particle gel via In-situ nanosilica is a novel method to procedure a robust bulk gel system for water control from fractured reservoirs.