f-Theory VISCOSITY MODELLING OF RESERVOIR FLUIDS

Kurt A. G. Schmidt¹, Sergio E. Quiñones-Cisneros², Arne O. Fredheim³ and Bjørn Kvamme¹

¹Department of Physics and Technology, University of Bergen, Allegatén 55, N-5007 Bergen, Norway.

²Institute of Physical Chemistry, University of Cologne, Luxemburger Str. 116, D-50939 Koeln, Germany.

³STATOIL Research & Development, Arkitekt Ebbellsvei 10, Rotvoll, N-7005 Trondheim, Norway.

The phase behaviour, density and viscosity of petroleum fluids are important properties for the development of petroleum reservoirs, production facilities and transport systems. As new oil and gas fields are being discovered at increasingly more severe temperature and pressure conditions, the selection of an accurate approach to model these properties at relevant conditions is becoming increasingly important each year. Recently, an overall modelling approach, that can be based on commonly used cubic equations of state, the friction theory for viscosity modelling and a new oil characterisation method has been shown to accurately determine the phase, density, and viscosity behaviour of a wide range of petroleum fluid systems ranging from natural gases to heavy crude oils.

In this presentation the applicability of this overall modelling technique to reproduce experimental saturation points, densities and viscosities of a number of reservoir fluids will be illustrated. Further unpublished measurements will be presented in order to expand the data set required for the validation and the development of f-theory predictive models. Combined with previous petroleum fluid modelling investigations, the obtained results will be used for an improved temperature dependency parameterization of the f-theory viscosity parameters utilized in the model. In addition to presenting new data sets, this investigation will assist in the development of the predictive capability of the f-theory as opposed to just a modelling tool for petroleum fluids.