Properties and plugging behaviors of smectite-superfine cement dispersion using as water shutoff in heavy oil reservoir

Abstract The high viscosity of crude oil, high permeability and strong edge water in some heavy oil reservoirs usually result in the failure of traditional water shutoff agents. In this paper, a novel water shutoff agent, the smectite-superfine cement dispersion, was produced based on traditional cement plugging agent. The high temperature stability test, simulated formation injection test and plugging strength test were conducted to evaluate the water shutoff performance. The results showed that the smectite-superfine cement dispersion exhibited perfect water shutoff performance and could fit into reservoirs with different permeability values by adjusting the cement content. The SEM analyses indicated that the hydration productions of superfine cement and smectite grew in a crisscross way and formed a stable microstructure, which ensures the composite with high strength.