Investigation of multiphase flow in Ashuganj - Bakhrabad - Demra pipeline

Abstract

Ashugal\i.l3akhrabad-Dcnll'a pipelinc is operated by Gas 1'ransmission Company Limitcd (CTCl.) and it carries almosl 40% ol'lhe nalural gas li'om l\onn Easlern pan [0 ~e1Ural regioll i.e. Dhaka region of Bangladesh. The pipeline lcngth is 130 km and diameter varies from 30 inches to 20 inches. l'rom operation~l point ofvievv" it is very impol1ant to study tnc !lOV'!behavior and pressure profile ~s it supply ga> to muny im)lor[a11l install~tions like power )llant~, t"rtili~er lactor)' and olher Lndustries. MultLpnase flow \'ariable~ are key parameters for studying thc tlo\v p~tlern in terms of 'l\vo-Phase !low. Sdorc studying the t\\'O phase flow in tni, pipeline, mea.,uremenl ,,[condensate I'm each n"" mte, at dLikrcl1llocmions are important. The ohjective or tills work is to invcstignte multiph~se flow in Ahug,mj-Baknrabad- Demra(A13I.l) pipeline with the dala provided by GTCL. ln tnis thcsis, tncorctienl Qmount of wndelNlte gencrated WlIScalculated by the Fla,h and Heal Balance melhod by a,suming that g~s compo,ilions were not changed significantly ovcr a pcriod of time. Thcll the prcdicted condensate values were ~ompared with the measured values givcn by thc G'ICL "nd found Flash method calculated thc volume of conden,ate with 25% errol'. A trend analy,i, was dOLleand found that flash correlation predicls the mea,ured trel1u hetter th~n othcr correlation Then measlLL'edcondensate valucs collccted from GTCL were uscd to calc\ll,lte the Tw()-Pha~e now parameters. Herc I'aitcl and Duckier stlatined equilibrium model 1,)[ hotizontal and ne~t hori70nwl pipe.' wa, used. Flow pa[terlLs tor dilTerent pipe segments were evaluated On the basis of Taitcl and Duckier model ~tratified Fl"", pallem was tound in every .,ectioll orth~ pipe. Altcr c,wbti,hing the flow p8ttern. S\litable rr~\slLL'e prcdicting correlation,> \\'ere identilied lor Two Phase and Singlc ph~'e 110wfrom the ILtcmture. Pressure calculation by various methods (Marching Algorithm, Weymoulh, Panhandle A, Pal1handIe 13and by Fekete So1\ware) \vCl"Cdone for each 8egmellts. Comparisoll betwcen cakubted pres,>ureand mcnsured pressure data gave a elear idca about Bpplicatioll of the correlations and limiting f,lelor,. Errm analysis was done fol' different correlation to I-Lnd a suitable correlalion for a segment of the pipe, No s;ngle con-elatioll founcl best for the cnter length llf th~ pi1'£. Panhand Ie 13"'QSfound the he~l p£rrorm ing prcssure correlati on, for Segment-\. Segment-:' "here absolute average error value, for all th£ correlations \\'ere les' than 5%.