Practice of downhole sampling in multiphase flows. Part 3: Estimation of the initial reservoir oil properties based on the results of distorted samples studies

Aim. The paper presents examples of the results of assessments of the properties of the initial reservoir oil in the study of distorted samples of reservoir fluids.

Methods. Sampled:

1) Downhole samples of non-volatile oil in the conditions of a gushing inflow of the first well.

2) Wellhead samples of volatile oil in conditions of a gushing inflow of depleted reservoir.

A set of standard PVT analysis was performed on the samples. The wellhead samples were recombined using a heuristic algorithm developed by the authors for calculating the composition of a component-by-component recombination gas.

Results. The application of the methodology for working with samples taken in multiphase flows is illustrated. Recommendations are given on some optimal set of studies.

Conclusion. the results of the work are recommended to be used in the development of educational materials and taken into account when planning work on sampling reservoir fluids.

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