IR-Method for Determining the Water Contents in a Water-Oil Emulsion Flow

About the authors:

Evgeny V. Zaitsev, Postgraduate Student, Department of Mechanics of Multiphase Systems; Engineer, Basic Department of Oil and Gas Flow Measurement, Physicotechnical Institute, University of Tyumen; welin151992@mail.ru

Sergey G. Nikulin, Head of the Basic Department of Oil and Gas Flow Measurement, University of Tyumen; s.g.nikulin@utmn.ru

Anatoly N. Shuvaev, Dr. Sci. (Tech.), Professor, Industrial University of Tyumen; anshuvaev46@mail.ru

Abstract:

The problem of moisture meter of water and gas streams remains unsolved yet, though its urgency is growing. The existing methods for determining the moisture content in the gas-liquid mixture stream have intractable shortcomings and limitations. In addition, the accuracy of existing methods depends heavily on many factors (including water salinity, grade of oil, dispersity and uniformity of the flow, among others) and often does not meet modern requirements.

This article reviews the methods for determining the moisture content of crude oil, which have received the greatest practical application, giving their main shortcomings. The authors focus on the IR-method and its place in the moisture meter of water-oil streams in more detail, describing the theoretical bases of its application. The advantages of the IR-method and its main limitation are given, as well as a method for eliminating this restriction.

This study aims to test the IR-method for determining the moisture content on a real water-oil flow of an emulsion and determining the appropriateness of its application. The authors have done an experiment to test this method at the pouring stand at the watercut points from 0 to 90% in steps of 10%. Based on the regression equation obtained, the water cut values at the control points have been calculated and compared with the true values. The maximum reduced error was 11%. The obtained results confirm the expediency of using the IR-method for determining the moisture content in the crude oil stream. In addition, the experiment has shown that it is inappropriate to use wavelengths with large absorption coefficients, as it requires limiting the thickness of the translucent layer to the values of no more than 1 mm.

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