USE OF A NEW MISCIBLE AGENT AS A PERCEIVED NEED FOR UZEN OIL FIELD DEVELOPMENT

Abstract

The Uzen oil field development (in the West of the Republic of Kazakhstan) over a long period is carried out with the miscible agent use, in which the Caspian Sea water is used. Due to the urgency of the problem of optimizing the enterprise costs and minimizing the risks of oil production loss, it became necessary to switch to another miscible agent for the following main reasons: significant costs for repairing wells due to active corrosion of underground equipment (aggressive water of the reservoir pressure maintenance system; using sea water (the main water pipeline length is 150 km, from the city of Aktau; the water pipeline is in poor technical condition to ensure stable and requires constant repair and restoration work); the shortage of oil production due to the frequent interruption of the seawater supply. To determine the possible source of «external» water for technological needs and injection into the reservoir pressure maintenance system of the Uzen oil field, unprepared sea water from the city of Aktau (the current situation) and albenomanskaya water of the Uzen oil field were considered. The article presents the precipitation study results when mixing reservoir and injected water in the conditions of the Uzen oil field. The chemical analyzes results of various water samples are presented and summarized, and the compatibility of their mixtures is assessed experimentally and calculatedly by mixing waters at temperatures of 36 °C and 60 °C with a shutter speed of 24 hours. Studies with samples from the following objects were carried out: water, formation water from GU-74 and GU-80. According to the laboratory research results, flooding of albsenomanian water is preferable to seawater and is cost-effective, since it is characterized by the maximum NPV value. The balance reserves of the ground- water of the albsenomanian aquifer system for the reservoir pressure maintenance system of the Uzen oil field are approved for a 27-year service life and are sufficient. An action plan was developed for switching to albsenomanian water with the implementation of all the necessary preparatory work.