Известия Томского политехнического университета: Инжиниринг георесурсов (Jul 2022)

IMPROVING THE EFFICIENCY OF OIL WELL KILLING AT THE FIELDS OF THE VOLGA-URAL OIL AND GAS PROVINCE WITH ABNORMALLY LOW RESERVOIR PRESSURE

  • Dmitriy V. Mardashov,
  • Maxim N. Limanov

DOI
https://doi.org/10.18799/24131830/2022/7/3707
Journal volume & issue
Vol. 333, no. 7
pp. 185 – 194

Abstract

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The relevance of the research is caused by the insufficient technological efficiency of the killing compositions used in the fields of the Volga-Ural oil and gas province for underground workover of wells. The solutions’ viscosity at the bottom of the well is not sufficient and passes the killing fluid filtrate through reservoir, which leads to the absorption of the process fluid and clogging of the bottomhole formation zone. Insufficient values of critical shear stress also affect the efficiency of killing operations. Low values of shear stress indicate excessive mobility of the process fluid in the wellbore. The main aim of the research is to compare the properties of the developed polymer killing composition with the properties of the already used composition with a similar mode of action, as well as compare the properties of the developed oil gel with the properties of invert emulsion solution used in the fields. Another aim is making a conclusion about the data obtained for new compositions in comparison with the old ones. Objects: well killing fluids used in the fields of the Volga-Ural oil and gas province, as well as developed polymer compositions and hydrocarbon-based fluids. Methods: imitation of reservoir processes, placement of existing killing compounds in installations that create reservoir conditions and further measurement of their properties; carrying out similar operations with new compositions to check the convergence of the results; analysis of the data obtained, comparison of the properties of various compositions with each other. Results. The authors have obtained the comparative characteristics of the main properties of blocking compositions, such as: corrosion rate, effective viscosity, complex viscosity, static shear stress, ultimate shear stress, and degradation time. The results obtained allow us to recommend the developed compositions for use in the fields of the Volga-Ural oil and gas province.

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