SIMULATION OF POLYMER FLOODING APPLIED FOR OIL FIELD IN PHITSANULOK BASIN

Abstract

This paper examines 2 questions: (1) the study and comparison of oil recovery efficiency between the best case of waterflooding and polymer flooding by using the reservoir simulation technique and(2) the application of the discount cash flow to optimize the polymer flooding selection from each scenario under current Dubai oil prices. Three sizes of oil fields are modeled in an anticline reservoir structure with the original oil in place (OOIP) of 100, 30, and 5 million barrels respectively. Each oilfield has many production methods using different polymer concentrations and injection periods. In the large size reservoir model A100, oil recovery has an increase from waterflooding of 3.86-7.24%OOIP. The polymer flooding has an internal rate of return (IRR) range from 28.40-43.76% and a profit to investment ratio (PIR) of 0.37-0.51; the best case scenario is the one that used a polymer concentration of 1000 ppm and an injection period of the 3rd-11thyears and which has a net present value (NPV) of$170M. In the medium size reservoir model A30, oil recovery has an increase from waterflooding of2.42-5.48% OOIP. The polymer flooding has an IRR range from 53.91-56.76% and a PIR of 0.36-0.40;the best case scenario is the one that used a polymer concentration of 1000 ppm and an injection period of the 3rd-10th years and which has an NPV of $53M. In the small size reservoir model A05, oil recovery has an increase from waterflooding of 4.39-4.62% OOIP. The polymer flooding has an IRR range from20.95-21.73% and a PIR of 0.66-0.76, and the best case scenario is the one that used a polymer concentration of 600 ppm and an injection period of the 4th-20th years and which has an NPV of $15M.