## 4 Experiments of Molecular Deposition Film Throughput
### Experimental Results and Analysis
#### 4.2.2 Optimal Injection Concentration  
Following water flooding, a continuous injection method was employed to introduce molecular deposition film drive agents aimed at further enhancing oil recovery rates. This approach ensures the formation of a uniform film on the rock surface by continuously and steadily injecting these agents into the reservoir. Such a film effectively reduces adhesion between oil and solid surfaces while improving fluid movement characteristics within pore spaces. To assess the impact of varying concentrations of molecular deposition film drive agents on oil displacement efficiency, experimental comparative analyses were conducted using multiple concentrations (100 mg/L, 150 mg/L, 200 mg/L, 250 mg/L, 300 mg/L, 400 mg/L, 500 mg/L, 700 mg/L, 900 mg/L, and 1000 mg/L) of molecular deposition film agent solutions. Each concentration group was rigorously controlled to ensure both reliability and repeatability in the experimental results. The test results for oil displacement efficiency across different molecular deposition film drive agent systems are presented in Figure 4. The data indicated that oil displacement efficiency significantly increases at higher concentrations (exceeding 400 mg/L). Specifically, an increase of 13.27% in oil displacement efficiency was observed at a concentration of 400 mg/L. This increased to 14.41% at 500 mg/L, reached 15.03% at 700 mg/L, further improved to 15.68% at 900 mg/L, and finally reached 16.12% at 1000 mg/L. These findings suggest that once the concentration surpasses a certain threshold level, molecular deposition film drive agents can substantially enhance oil mobilization during water flooding processes, thereby effectively improving overall oil recovery rates. Figures 5 and 6 depict the increase in oil recovery efficiency using the membrane method and the correlation between residual oil saturation after membrane flooding and the concentration of the membrane agent. The black lines in the Figure 6 delineate the boundary between water flooding and molecular deposition film flooding. The left side of the line corresponds to the water flooding stage, while the right side indicates the molecular deposition film flooding stage. Based on the experimental findings, it is evident that an increase in the concentration of the membrane agent corresponds to a marked improvement in membrane flooding effectiveness. This enhancement results in a significant reduction in residual oil saturation within the reservoir, which is critical for optimizing oil recovery rates. The correlation  
Figure 4: Experimental results of increasing oil displacement efficiency of molecular deposition film agent systems with different concentrations. Figure 5: Residual oil saturation after membrane flooding at different membrane agent concentrations. Figure 6: Oil displacement efficiency and water content curve of 400 mg/L concentration molecular deposition film flooding. between concentration and efficiency highlights the necessity of refining chemical formulations employed in enhanced oil recovery processes. From an economic standpoint, it becomes essential to consider input/output ratio analyses when determining optimal operational strategies. In this context, an ideal concentration for the membrane agent has been identified at 400 mg/L. This concentration effectively balances cost-efficiency with performance efficacy, ensuring judicious resource utilization while achieving substantial advancements in oil displacement. However, specific factors influencing overall efficacy during implementation must be taken into account. For instance, adsorption of the molecular deposition film agent near wellbore areas can result in localized variations regarding agent availability and effectiveness. Dilution effects from formation water should also be considered, as they may alter the effective concentrations of injected agents over time.