Исследование зависимости эффективности технологии нестационарного заводнения от продолжительности полупериода работы/простоя нагнетательных скважин в цикле при разработке высокопродуктивных неоднородных коллекторов маловязкой нефти

Abstract

Background Efficiency of non-stationary flooding depends on the unknown half-cycle period / idle time as it was obtained on the operating facilities of the Kumkol field. Is it critical to use the exact value of work / idle time of injection wells instead the average time? How can the work / idle time influence the oil recovery factor? Aims and Objectives To establish the best operating periods of non-stationary water flooding in order to obtain the maximum efficiency for the reservoir with light oil. Methods Hydrodynamic modelling. Results 1. Increase of the half-cycle period increases the operating parameters as well, such as watercut or oil production rate in a range from 25 % for relatively high permeable layers (0.1 µm 2) up to 170 % for low-permeable layers (0.001 µm 2). The watercut decreases in a range from 2.7 % up to 13 % for the same layers correspondently. 2. It was noticed, that the technology has the period of negative effect (when the oil production rate decreases) in the initial operating time for the low-permeable reservoirs. Increasing the half-cycle period the negative effect could be increased as well. 3. Oil recovery factor has the positive value for all the half-cycle periods, but for the maximal efficiency it is necessary to obtain the specific operating / idle time depending on the permeability ratio of high and low permeable layers. Despite this, the raise of the efficiency is not so big, as a result the operating / idle time could be chosen in wide range of values.