Search

This paper proffers some guidelines for using a surfactant-polymer (SP) flooding operation so that the feasibility and profit can be optimized. Many successful projects have shown that surfactant-polymer flooding is an effective means to improve oil recovery after or during water-flooding. Here, the guidelines for evaluating whether a surfactant-polymer flood is suitable for a given field are developed and the procedure for a full implementation is summarized. These guidelines cover primary screening, laboratory measurements, reservoir simulation, economic analysis, pilot testing, and field application. Detailed methods also are presented for the optimization of chemicals (including compatibility tests between chemicals and reservoir fluids and rock), well pattern and spacing preparation, and slug and injection process design. The correlations between the above phases of operation are also emphasized. The work offers reservoir engineers a reference for decision-making in SP flooding.

In this research, both reservoir simulation and well testing were employed to investigate the average reservoir pressure in the Xing 1-2, a multilayer sandstone reservoir. The concrete methods included the well testing, Peaceman, and volumetric weighted average method (VWA). The average reservoir pressures for the last three years of the monitoring wells were calculated. The results showed diversities among three methods at each well pattern. The factors which caused diversities in three methods have been categorized, like the geological uncertainties, production impact, the difference in mathematical methods, etc. The wells in low pressure zones were detected and analyzed. By reducing the influence of referenceless interpretations, the system provided more accurate interpretations. The results were also used to optimize the monitored wells and to offer reference for the improvement of the injection and production system.