Evaluation of the flow regime identification capability of gamma-based multiphase flowmeters
Date
2021-04
Authors
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Journal ISSN
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Publisher
Federal University of Technology, Owerri
Abstract
The application of a single beam, dual energy gamma densitometer unit in determining the flow patterns of vertically upward multiphase flow was investigated. A fast-sampling (250Hz) gamma densitometer was installed on a 3" schedule 160, 11.1mm wt inlet manifold riser in an onshore production facility, Delta-X, in the Niger Delta. Gamma radiation attenuation data for the caesium-137 radioisotope-based densitometer was collected for Well-X effluent of oil, water and gas mixture. Classification of the multiphase mixture's flow regimes was investigated through the analysis of the probability mass function (PMF) chart obtained from the soft gamma count data. The prevalent flow regimes identified during the trial period were bubbly, slug, churn, annular and transition (bubbly-slug and churn-annular) flows. The result showed consistency with similar test facility studies conducted using air, diesel oil and portable water. An economic model was proposed for evaluating the economic viability of replacing existing test separators with
multiphase flowmeters. Results from the economic analysis showed that given the current cost of multiphase flowmeters, it is not viable to replace existing test separators with multiphase flowmeters on a per well basis. The valuation, however, favoured replacing an existing test separator with a single multiphase flowmeter. Sensitivity study indicated that installing multiphase flowmeters on a per well basis will be economically viable with over
60% reduction in multiphase flowmeter present CAPEX for an 8-well production facility
Description
A Masters on gamma-based multiphase flowmeters
Keywords
Gamma densitometer, multiphase flow, test separator, flow regime, net present value, sensitivity, petroleum engineering
Citation
Gbaden, E. T. (2021). Evaluation of the flow regime identification capability of gamma-based multiphase flowmeters. (Unpublished Masters thesis). Federal University of Technology, Owerri.