Synthesis and performance evaluation of a new kind of gel used as water shutoff agent

Abstract

In this paper, a kind of modified cellulose as a raw material of a water-based gel is studied systematically. Its migration performance is good and its solution is Newtonian fluid in porous medium. And more importantly, a water-based gel is synthesized with modified cellulose, acrylamide, N,N′-methylene-bisacrylamide and persulphate. An appropriate formula of a gel is 0.8 wt% modified cellulose, 2 wt% acrylamide, 0.1 wt% cross-linking agent and 0.05 wt% initiator. The initial viscosity of this gelling solution is 72 mPa s and the gelation time is 15 h at 70 °C. After gelation, it is a strong gel and the elasticity is more outstanding than the viscosity. Its applied range in formation environment is the temperature of 60–90 °C, the salinity of 0–100 g/L and the pH value of 6–9. The experimental results show that the gel system can be better applied to conformance control of the heterogeneity reservoir.