4. Results and discussion
4.1. Effect of total concentration membrane-forming materials
The integrity of semi-permeable membrane has prominent
effect on osmotic pressure (Durbin, 1960). When the concentration
ratio of high-solute fluid and low-solute fluid was 2, the effects of
total concentration of membrane-forming materials on EOR from
fractured rock were investigated as seen in Fig. 4. The rate of EOR
increased with the total concentration of membrane-forming
materials. In addition, the rate of EOR is zero without membraneforming materials. The proposed theory is that the copper hexacyanoferrate membrane is more integrate with higher precursor
concentrations, which results in greater hydrostatic pressure in
matrix rock and higher oil recovery.