Bench studies of gas accumulation removal from pipelines by pumped liquid flow

UDK: 622.692.4

DOI: 10.24887/0028-2448-2026-2-95-102

Key words: main pipelines, gas accumulations, removal of gas accumulations by the flow of pumped liquid, an experimental stand, an error in predicting the outward velocity

Authors: A.A. Korshak (The Pipeline Transport Institute LLC, RF, Moscow); M.I. Valiev (The Pipeline Transport Institute LLC, RF, Moscow); M.Z. Yamilev (The Pipeline Transport Institute LLC, RF, Moscow); A.S. Korshak (Ufa State Petroleum Technological University, RF, Ufa)

The operation of oil pipelines involves the formation of gas accumulations at elevated points. The main reason for this is the occurrence of temporary pass points. A rational way to eliminate gas accumulations is to remove them with a stream of pumped liquid, since this doesn’t require the introduction of additional equipment or chemicals into the pipeline. For such operations, it is necessary to have adequate dependencies describing the conditions for the removal of gas accumulations by the pumped liquid flow. The article provides a critical overview of previous studies to determine the conditions for the complete removal of gas accumulations. It is shown that some of them are purely theoretical. Another part is a summary of the results of experiments on small diameter pipes with manifested capillary effects. Water, which significantly differs from oil and oil products, was often used as a model liquid. Some studies considered the conditions not for the removal of gas accumulations, but for their equilibrium under the influence of the flow of pumped liquid. The article describes a unique stand that enables to study the activity of gas accumulations in a pipeline with a variable profile, including sections of DN100 pipes. The results of experimental study of the mechanism of gas accumulation removal from the inclined downward pipeline are presented. Influence of surface tension on outflow velocity was revealed. It was shown that previously known formulas for predicting the flow rate, which provides a one-time removal of gas accumulations, have a significant error.

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