In the petroleum industry, cyclonic separators are acceptable as hydrocyclone,mist eliminators, separator internal device and compact metering package.Weight and small footprint requirements for applications such as subseaseparation, downhole separation, and compact gas monetization systems isdriving interest in using cyclonic separator for bulk gas-liquid separation.Unfortunately, the challenge of coping with the effect of unsteady inlet flowbehaviour on the separator performance limit it acceptance for bulk gas-liquidseparation. Fundamental understanding of the flow behaviour inside theseparator under various inlet flow conditions is required to deal with thechallenge. While most published work have addressed flow behaviour in thelower half of cyclonic separator, this thesis concentrated on the upper half.A gas-liquid pipe cyclonic separator was setup at Cranfield University for bulkgas-liquid separation. Large amount of data at the inlet and upper part of theseparator were acquired using electrical resistance tomography (ERT), wiremeshes sensor (WMS), conductivity hold up probe and pressure transducers.The acquired data were used in analysing flow regimes, upward swirling liquidfilm (USLF), zero-net liquid flow (ZNLF), liquid holdup and, general separatorperformance.It was found from analysis of USLF data that a maximum USLF height exists forevery constant superficial liquid velocity. A correlation based on dimensionlessnumbers was proposed for predicting this height. Experimental results on ZNLFshowed that a critical ZNLF also exist above which liquid carryover can take place. The liquid holdup for this critical ZNLF was measured under separatoroperating condition using ERT and a correlation for predicting the liquid holdupwas proposed. Four flow regimes were identified as swirling annular, light-mistheavy-mist and churn using visual observations, ERT, WMS and pressuretransducer. A flow regime map was proposed based on gas and liquid Froudenumber. The performance based on the operating envelope for liquid carryoverand pressure drop for horizontal and 270 downward inclined tangential inlet wascompared. It was concluded that the separation performance was marginallyimproved by using an inclined tangential inlet. The pressure drop for the inclinedinlet was far greater than that of horizontal inlet. Two inlet nozzles with D–shapewere used for separation enhancement. The nozzle that reduces the diameterof full pipe bore by 25% gave slight improvement but also gave the greatestpressure drop. The nozzle that reduced the full pipe bore diameter by 50%performed poorly.
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