The Numerical Simulation Research On Optimization Of Polymer Flooding Parameters Of Horm&Nantu Oilfield In Oriente Basin

Horm&Nantu oilfield in Oriente Basin has a high reservoir temperature and high salinity. Generally, the temperature of each block in 94℃-106℃ and salinity of formation water is 71512.05 mg / L. In this typical high temperature and high salinity conditions, it has been more than ten years since the wells input production and water flooding development. until May 2014, water content by waterflood development is up to 85.16%. Most of the oil productions decrease rapidly and reservoir formation exist hypertonic mainstream channel. Therefore, the primary task is to stabilize oil production and control water content at present and take development adjustment measures in order to improve oil recovery. This paper selects temperature resistant and anti-salt polymer to make polymer flooding.At present, polymer flooding technology is recognized by most of domestic and foreign oilfields and widely applied in tertiary oil recovery technology. With in-depth study of polymer flooding theory and laboratory experiments, some new special polymers are developed to improve the oil displacement efficiency and broaden the application scope of polymer flooding. In this paper, combined with the actual oil reservoir conditions, hydrophobic association polymer APP5 is selected according to the previous research of temperature resistant and salt resistant polymers as displacement agent. In the indoor test, experiments of temperature resistance performance and stability performance under the actual conditions of the reservoir are carried out.Before the optimization of polymer injection parameters, this paper firstly reviews the dynamic and static data provided by the oilfield, describes the characteristics of the basin, the related physical properties of the rock and fluid in the reservoir, and the dynamic state of the oilfield exploitation. According to the actual production data, the development effect of water flooding is evaluated from four aspects: water drive recovery, water cut, water storage rate and water injection quantity. The evaluation results show that the water flooding effect is not ideal. Based on 3D geological model established in the petrel, history matching of produce dynamic parameters(production, cumulative production, water cut rate) are made by eclipse software, remaining oil distribution of each layer plane and reservoir longitudinal is described, and each layer’s residual oil volume and remaining oil enrichment zone are given.Based on the numerical research of water flooding, varieties of development programs from four aspects of the polymer flooding injection concentration, velocity, the number of PV and injection timing are designed separately. Different schemes of water rate and ultimate recovery and enhanced oil recovery are compared. Then the best parameters of the polymer injection are optimized and a development program is obtained. Finally, benefit of the development program is analysed from the economic point of view.