The Open Petroleum Engineering Journal

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1 Send Order or Reprint to 0 The Open Petroleum Engineering Journal The Open Petroleum Engineering Journal Content lit available at: DOI: 0.74/ RESEARCH ARTICLE Mechanim or Controlling Sand-Induced Corroion in Horizontal Pipe Flow o Sand Crude Oil and Water Samuel Ehorame Sanni * Sam Sunday Adeila Ambroe Nwora Anozie and Oluranti Agboola Department o Chemical Engineering Covenant Univerity P.M.B 03 Ota Ogun State Nigeria Received: March 3 07 Revied: July 3 07 Accepted: Augut 3 07 Abtract: Background: The preence o and particle and aociated water in crude oil call or eriou concern when the low condition leading to low tratiication in an uptream petroleum pipeline become igniicant. At uch condition problem uch a and depoition and water containment on the pipe wall may reult in conequence uch a and-induced corroion mechanical ailure pipe atigue reduced low area lo o production and pipe blockage which are till currently unreolved by conventional and current model. Objective: A modelling approach wa adopted to control the condition leading to and-induced corroion and other related problem caued by low tratiication in the uptream petroleum ector ince conventional method adopted to creen and only contribute to the problem. Alo to date mechanim and model exit or other corroion type uch a CO H S acid-induced corroion etc. but none currently exit or and-induced corroion. However the concept o orce-competition or dimenionle number wa adopted uing a modelling approach to reolve the problem. Method: Thi reearch work reolve the ituation by mean o a three-phae model which incorporate and crude oil and water phae in it ma and momentum balance equation while taking into cogniance the eect o eddie. The three-layer model etablihed in thi work ha it origin in a two-phae and-crude oil ytem and baed on current literature a modelling approach that conider the low o and crude oil and water ha never been adopted to tackle the problem o and-induced corroion caued by aociated water a a timulant or corroion. Concluion: The etablihed model gave an accuracy o 99% when reult rom the model were compared with and and crude oil production data obtained rom the ield. Baed on the model reliability low mechanim/dimenionle number were ued to acertain critical low condition in order to be able to avoid ituation leading to and depoition and-induced corroion and other related problem. Baed on the reult obtained the etimated Euler number revealed that the 8 m point o the pipe i at rik due to the impact o the and-depoit-drag-orce on the pipe wall. Alo the etimated Froude number were indicative o the -8 m point a depoit/corroion prone area. Keyword: Dimenionle number Flow tratiication Sand depoition Sand-induced corroion Three phae low.. INTRODUCTION Many pipe low cenario are characterized by the component that make up the ytem. Uptream petroleum luid are oten known to comprie o three component uch a and crude oil and water or our component namely * Addre correpondence to thi author at the Department o Chemical Engineering Covenant Univerity P.M.B 03 Ota Ogun State Nigeria; Tel: ; adexz3000@yahoo.com /7 07 Bentham Open

2 Mechanim or Controlling Sand-induced Corroion The Open Petroleum Engineering Journal 07 Volume 0 and ga crude oil and water which mut be tranported to the well head rom reervoir or urther action. Adeyanju and Oyekunle [] developed a model or predicting the bottom hole preure o a well. Their model gave good perormance with higher level o accuracy becaue o it ability to incorporate the onet and inluence o anding/and drag on the low velocity o the lowing tream which in turn reult in higher luid vicoitie and preure drop than could be obtained with previouly etablihed model. Berrone and Marro [] carried out pace time adaptive imulation o the problem aociated with laminar low. The problem were reolved uing the Navier Stoke equation or teady and unteady tate condition. Boulanger and Wong [3] carried out an experimental tudy o the ituation leading to and depoition or and lurry upenion in a horizontal tranparent pipe loop ytem; they etablihed and determined two important velocitie namely the and depoition and the minimum and tranport velocitie. Chu et al. [4] applied a two-way coupled Computational Flow Dynamic (CFD and Dicrete Element Model (DEM to a multiphae low cenario o a mixture o air water and ine o magnetite with their movement and interaction determined uing the Navier Stoke and Newton equation; and ound that at low luctuation/low rate within a region o the cyclone particle ettling under gravitational inluence did o at longer reidence time. Darvazani et al. [5] carried out an experimental invetigation o the eective and thermo-diuion coeicient o helium-nitrogen and helium-carbon dioxide gaeou mixture through porou cylindrical container illed with gla phere. They applied the tranient tate method in etimating the thermo-diuion and Fick coeicient o diuion; the model prediction were in agreement with experimental meaurement. Simulation o laminar low o and and crude oil in a horizontal oil well ha been modelled [6] however the model cannot handle ituation involving turbulent low. Giveler and Mikataranian [7] gave correlation or determining riction actor and Reynold number o a particle in laminar and turbulent low. Other work on multiphae low have their variou application ome o which include the work o Horender and Hardalupa [8] who carried out vortex imulation o a two-phae dilute particle laden ytem to determine the correlation between luid-particle motion and the traner o turbulent kinetic energy between both phae. From their inding the particle Stoke number wa inluenced by the particle concentration and lip between both phae. Alo the particle howed reduced luctuation due to the particle concentration/population at a given point. Flow operator are ometime aced with tranport challenge including: and depoition lugging partial pipe blockage corroion abraion mechanical wear reduction o eiciency low oil recovery rom the line and well hut down [9] when a mixture compriing the aorementioned challenge i to be tranported rom the well bore to the well head. In thi work the low o and crude oil and water in a horizontal pipeline wa conidered in order to be able to decribe adequately and accurately by mean o a model the orce competition or interaction taking place in the ytem. A tudy wa carried out on thixotropic interparticle interaction o ilica and non-ionic polymeric particle in an aqueou medium [0]. Baed on their inding the obtained reult compared avourably with publihed literature on the ubject. Liu et al. [] carried out a numerical imulation o the Reynold tre on the interaction in a ga-particle binary ytem. The reult howed that the Reynold tre near the wall and at the concentric region were reponible or the tratiied low that i it wa higher at the wall than in the concentric region o the pipe. The review o Rahmati et al. [] on and prediction model aert that numerical and analytical and tranport model have ome meaured degree o ucce in quantiying and determining the amount o and and the onet o anding in reervoir but are deicient in predicting and ma and rate o anding in petroleum reervoir hence there i a need to improve the exiting model and technologie. Flow direction are oten inluenced by orce which provide inight into the prevailing orce mechanim reponible or tranport. When the urace o the reervoir luid at the well bore i heared the inertia orce tend to ditort the interacial tenion thu the luid gain momentum and i given a lit o the ormation zone. The mixture then low through peroration into the oil well lined with pipe through which the reervoir luid low. The mechanim conidered here are inertia orce vicou orce momentum diuivity molecular diuivity gravity and preure orce [6 3 4]. Particle depoition in luid-olid ytem reult rom preure drop where the ytem become tratiied with the dierent layer experiencing interacial orce and preure eect [5]. Numerical imulation o the two phae low in a particle-laden channel were carried out by Wang [6]. Streaky and cloudy orientation o particle in the tream were known to be weakened by increaed inertia orce. Turbulence modulation increaed with particle loading at the wall and reduced a particle concentration dropped. Zhou et al. [7] carried out the numerical imulation o a hale-haker/vibration equipment or creening and during the tranport o petroleum luid. The particle trajectory wa imulated uing the dicrete element method and it wa aerted that particle ize ha a great inluence on it tranport velocity and the particle ilter ratio i a unction o the creen vibration requency.

3 The Open Petroleum Engineering Journal 07 Volume 0 Sanni et al. In order to olve the problem o and-induced corroion o petroleum pipe caued by low tratiication reulting rom and depoition and water accumulation in the line there i need to look beyond the already exiting luidparticle model or multiphae low model in the bid to etablih an appropriate model or determining the condition that can caue and-induced corroion or mechanical wear o petroleum pipeline. Thi i becaue although the model dicued were etablihed or luid-particle ytem none o the work cited and thoe o current literature on the ubject have etablihed a model approach to tackle the problem o and-induced corroion o petroleum pipe which centre on uing the concept o dimenionle number alongide the incorporation o and water and crude oil concentration and velocity term. Previouly etablihed model are or other particulate/and and water air/ga ytem but there i no model decribing the low cenario in a crude oil-and-water ytem in relation to and-induced corroion and depoition mechanim. Alo the Reynold number i the mot popularly dicued mechanim without emphai on other important low mechanim uch a momentum and molecular diuivitie Froude and Euler number.. DATA COLLECTION Field data wa generated uing low acilitie et up by ADDAX Petroleum in Owerri Imo tate Nigeria. Reervoir luid wa introduced into the well line (that i 78 t; 4 m pipeline by mean o a pump ituated at the well bore which link the wellbore to the lowing tubing head. The line had three integrated and creen/ilter located at the uction 8 and 4 m point o the pipe which helped to remove coare medium ized and ine and particle repectively. A Superviory Computer-Aided Data Acquiition Machine wa ued to obtain data rom the producing well. The produced and water and crude oil Feeder line were then ued to tranport the luid to a eparator rom which the amount o crude oil water and and were determined. Sand particle hardne (that i average particle hardne = 800 Vicker wa determined uing a pyknometer. The data obtained rom low meaurement are a indicated in Table. Table. Field meaurement or well B. Choke (- FTP (pia API (o GAS (c/d BSW (% BLPD (bbl/d BOPD (bbl/d GOR (- Pinj (pia GL rate (c/d Sand PTB (lb/bbl Development o the Three-Phae Model The three-phae model wa developed baed on the ollowing aumption: Sand particle are pherical and o ame ize. Sand and oil or and and water cannot mix. Oil i incompreible and the pipe i mooth. Eect o eddie i igniicant and depoit conit entirely o and. Oil i Newtonian and particle mobility i a a reult o the urrounding oil/water phae and the eect o orce including gravity luid-particle interaction and inertia orce. Detail on thee aumption and the developed model are preented in Appendice A and B repectively. ( ( w 0 t ( ( w 0 t ( ( w 0 t ( ( w w 0 t ( ( (3 (4

4 Mechanim or Controlling Sand-induced Corroion The Open Petroleum Engineering Journal 07 Volume 0 3 ( ' w t ' P ( ' ww ( ' g V ( w P w k ' (5 P ( w ( w w ( g V ( w w t (6 P ( ww ( wwww ( g Vm ( wm ww t (7 3. THEORY CALCULATIONS AND MODEL SOLUTION 3.. Determination o Model Contant/Calibration o Model The new model that i the three-phae low model wa calibrated baed on the explanation o Sanni et al. [3]. Finite dierence olution or the eparate equation were then etablihed with the dierent variable and lumped parameter etimated. The ma and momentum equation were olved baed on uptream data hown in Table. 3.. Boundary Condition Boundary condition were etablihed or each o the three component o the mixture volumeooil in volumeooil volumeoand volumeowater (8 = 59.47/49.38 = 0.58 (oil concentration at the inlet volumeowater in volumeooil volumeoand volumeowater = /49.38 = 0.36 (% water volume at inlet Then φ in = ( = 0. (and concentration at pipe inlet or 54.54/49.38 = 0.0 Since (9 (0 At the outlet out volumeoand ( volumeoand volumooil volumeowater outlet ( = 43.97/ = 0.05 i the and concentration at pipe outlet and the correponding ε and θ value (oil and water concentration repectively are: out volumeooil ( volumeoand volumooil volumeowater outlet ( = 0.0/ = 0.58 volumeowater out ( volumeoand volumooil volumeowater outlet (3 = 4.99/ = Boundary Condition or Sand Water and Oil Momentum Equation Equation 4 wa ued to etimate the concentration knowing the boundary concentration or the three component o the mixture.

5 4 The Open Petroleum Engineering Journal 07 Volume 0 Sanni et al. C l N C l N l l ( CN Ci 4 (4 Equal length at an interval o 6 m were marked out on the pipeline rom 6-4 m. It wa reaonable to alo aume equal change in and oil and water concentration ince it i evident rom the calculation that concentration only varied lightly between the pipe inlet and exit or all three component: or and at t = h rom the pipe inlet through to it outlet repectively. For crude oil the correponding concentration are: while or water the correponding concentration are In order to urther validate thi claim or a tubular or plug low ytem there i no variation in concentration with time at peciic poition in the pipe a there i no back mixing and molecule hitory i not known a the molecule in the mix low pat pace diplacing other molecule. The inlet velocitie or the and oil and water (that i m/ 0.37 m/ and 0.54 m/ repectively were calculated baed on the data along the irt row in Table and they were ued a inlet boundary condition or the momentum equation while 6.67 x 0-5 m/ 6.67 x x 0-4 m/ and. x 0-4 m/ were etimated a their correponding outlet velocitie. The boundary condition were etablihed baed on data with preure between pia which gave the leat amount o produced and but highet amount o crude oil Solving the Ma Conervation Equation Finite Dierence Formulae or the Ma Conervation Equation Equation 5-8 are the inite dierence equation or the and water and oil phae ma conervation equation repectively. l l l l i i i i l i ( l l l l i i i i l i ( l l l l i i i i ( D t T z l i (5 (6 (7 (8 The calculated λ = 5.66 x 0-4 and an average value or and diuivity wa obtained rom the value obtained at the inlet and outlet that i.3 x 0-5 m / o a to impliy the imulation. A olution wa etablihed or the ma conervation equation uing Equation 5-8 where l repreent poition and i repreent time e.g. 6 m away rom pipe inlet l+ = 6 m and time t = h. D t i the um o molecular and eddy diuivity term. By applying Equation 4 to the olid phae ma conervation equation the lat three point (that i the 6 m m and 8 m point are conidered in calculating the exit (4 m concentration. φ i l+ = 5.66*0 4 ( ( = The calculated exit concentration or and uing the three phae model = while at the ield the and concentration at the exit i ( *00% Hence % dierence/error = 0.3% and thi implie the predicted and concentration 0.05 at the exit per hour i 99.77% accurate when compared to the reult rom the ield conidering hour time tep and a total time o 4 hour. Similarly or water conidering the 6 m m and 8 m ection o the pipe the % volume o water i given by Equation 6: θ i+ l+ = *( * = The average total diuivity between the inlet and outlet i 3.86 x 0-5 and rom Equation 8 λ =.93 x 0-3.

6 Mechanim or Controlling Sand-induced Corroion The Open Petroleum Engineering Journal 07 Volume 0 5 At the ield % volume o water at the pipe exit = while the predicted volume % o water = % error = ( = 0.0% which i 99.9% accurate Applying Equation 7 to the oil phae ma conervation equation or an average um o eddy and molecular diuivitie o x 0-5 λ =.95 x 0-3 Conidering the 6 and 8 m ection o the pipe at t = h implie ε i+ l+ = *( * = The actual exit oil concentration = and the predicted oil concentration i % error = 0.007% which mean the reult i 99.99% accurate. To etimate the correponding amount o and rom the model experimental reult have to be conidered. Baed on meaurement 0.05 and concentration at the exit correpond to. pptb then rom inite dierence calculation give: (0.075* =.7 pptb which give 99.5% accuracy Finite Dierence Formulae or the Momentum Conervation Equation φw εw θw w were obtained by multiplying the volume raction o and oil and water by their correponding velocitie that i m/ 0.37 m/ and 0.53 m/ are the inlet velocitie obtained or and oil and water repectively while their correponding outlet velocitie are m/ m/ and. 0 4 m/. l l l l ki ( ki ki k i {( g P Pk l ( w w } ki (9 l i l l l ( i i i {( g P l ( w w } i (0 l i l l l ( i i i {( g P l ( w w } i ( Equation 9- are the momentum equation or the and oil and water phae repectively where: k = φw γ = εw and Ω = θw w Model Validation In order to conirm the new three phae model accuracy and production data obtained rom experiment were compared with the model etimate at the low condition; See (Table. Table. Crude oil and and etimate rom the experiment and model. Run (- Oil+water BLPD (bbl Amount Oil Exp. BOPD (bbl Amount Oil & Doan et al. [6] & Sanni et al. [3] model BOPD (bbl Amount Oil New model BOPD (bbl Produced and exp. (pptb (lb/mbbl Produced Sand Doan et al. [6] & Sanni et al. [3] (lb/mbbl Produced Sand new model (pptb (lb/mbbl

7 6 The Open Petroleum Engineering Journal 07 Volume 0 Sanni et al. (Table contd... Run (- Oil+water BLPD (bbl Amount Oil Exp. BOPD (bbl Amount Oil & Doan et al. [6] & Sanni et al. [3] model BOPD (bbl Amount Oil New model BOPD (bbl Produced and exp. (pptb (lb/mbbl Produced Sand Doan et al. [6] & Sanni et al. [3] (lb/mbbl Produced Sand new model (pptb (lb/mbbl Table give the reult obtained or and production data rom experiment a compared with thoe calculated uing the Sanni et al. [3] two phae model and the new model (that i the three-layer/phae model dicued in thi work that conider the water phae alongide and and crude oil. (i Evaluation o olid phae preure orce The olid and luid phae preure were determined by imply etimating the product o ϕ *p and ε*p rather than applying Equation alo known a the ingle phae Sthumiller [5] preure model a uggeted in Sanni et al. [3]. The conceptual deviation i more reaonable becaue the whole tream low a a mixture o phae thu the phae will only eparate out baed on the low condition and particularly the Reynold Euler and Froude number which are orce ratio o inertia to vicou orce preure to inertia and inertia to gravity orce repectively. Pi P z z ( z du ( R Co u z dt 8 (9Co 5 ( Note: The phae preure are actually product o the volume raction o the component o the mixture. (ii Evaluation o kinematic orce or olid phae momentum equation The kinematic preure equation a given in [6] i given by Equation 3. * h( Pk * w w * w w (3 Since and concentration i le than 0% throughout the pipe cro-ection it then implie that Equation 4 or dilute upenion applie [6]. Hence h(0. =.596 h 3 4 (.0 4( 0( 8.36( 9.44( (4 :. the correponding P k *705.4*.596* * kg/ m. When t = hour at the inlet there i no gradient in and concentration o the gradient multiplier make the unction undeined thu the product o P k /ρ and concentration gradient value can be calculated at other point ; ince Δz can be evaluated 6 m away rom pipe inlet where (ϕ = and t = hour there would be need to do ome evaluation to get the correponding h (ϕ Hence h ( =.5959 and P k = kg/m m away where (ϕ = 0.07 by calculation h (ϕ =.5950 and P k = 9. kg/m 8m away where (ϕ = 0.06 and by calculation h (ϕ =.594 and P k = 7.3 kg/m At the exit (ϕ = 0.05 h (0.05 =.593 and P k = kg/m

8 Mechanim or Controlling Sand-induced Corroion The Open Petroleum Engineering Journal 07 Volume 0 7 The ame procedure applie at other time along the pipe length conidering a time tep o one hour and a total time o 4 h. (iii Evaluation o ϕg Taking g = 9.8 m/ when t = hour at the pipe inlet then g = 0.5 x 0. x 9.8 = m/ = 0.5 x 0. x 9.8 = m/ 6m away rom pipe inlet (ϕ = then g = m/. The ame procedure applie at other point or t = hour and at urther time along pipe length conidering a time interval o hour and a time total o 4 hour. (iv Evaluation o εg When t = h at the pipe inlet ε = then * g and o on a explained or the olid phae. =.59 m/ * g = m/ and 6m away ε = then (v Evaluation o θg or the water phae At t = h at the pipe inlet θ = 0.36 then * g 6m away θ = then =.77 m/ * g and o on a explained or and and crude oil phae. =.77 m/ (vi Evaluation o w w ( o The interaction coeicient along the axial ditance were determined uing ( C wo w D *. 65 a ( (5 The reaon i becaue ϕ < 0.0 (dilute upenion To evaluate β there i need to calculate + and C D 0.05 d v avg d (6 and Svavg (7 Givler and Mikatarian [7] gave expreion or etimating the riction actor o a particle in a lowing luid or laminar low where Re Re 0.8 p (8 For tranitional low Re > 000 < 00 while or turbulent low Re i greater than 00 although ome literature ay turbulence begin at Re > 4000 baed on pipe diameter.

9 8 The Open Petroleum Engineering Journal 07 Volume 0 Sanni et al. 64 Re p (9 But Re p w w d (30 where Rep = particle Reynold number ρ luid denity = riction actor d = pipe diameter ε = luid concentration ϕ = olid concentration μ = luid dynamic vicoity w w = luid and olid velocitie repectively. The dimenionle topping ditance o a particle i a meaure o the ratio o: the product o the particle topping ditance (ditance o travel beore it meet an obtacle it riction actor and particle velocity to the kinematic vicoity o particle that i the ratio o particle reitance to the luid kinematic vicoity. When particle Reynold number R ep < 000 C D ( 0.5Re p Re p (3 but C D = 0.44 when R ep > 000 where: C D = drag coeicient However or 0. and concentration at the inlet w = m/ and w o = 0.37 m/. At z = 0 m uing Equation 5 β = kg/m 3. Thereore at the inlet where t = h ( w w implie * *( = 0.08 kg/m 3 6 m away β = 8.05 kg/m 3 then ( w w give: 8.05 * *(0.37* * = m / and o on. For the crude oil and water the ame procedure applie at all point down to the exit or the entire time Force Ratio Analye A orce ratio relationhip wa perormed in order to know the contribution o each o the orce already mentioned in ection.0 to the tranport proce. The combined mechanim o interet include Euler Froude Reynold and Schmidt number. Table 3 how the mechanim o interet and the variable they conit. Table 3. Mechanim and their variable. Item Mechanim Variable/Model Parameter A Inertia orce u (velocity and diameter ( ' w w d ( w w

10 Mechanim or Controlling Sand-induced Corroion The Open Petroleum Engineering Journal 07 Volume 0 9 (Table 3 contd... Item Mechanim Variable/Model Parameter B Preure orce ( w w ww or Re/mix vicoity ' ( P P d P ( P w ( w (preure denity and diameter h: C Vicou orce (kinematic vicoity velocity and diameter Re/inertia orce D Gravitational orce ϕ ' g εg and θg E Momentum and molecular diuivitie u d The value or the orce ratio are etimated thu: η and D (kinematic vicoity and diuion coeicient At 0 metre the preure orce are undeined. In eence no value wa etimated at 0 metre at all time. When t = (i Euler number = Preure orce Inertia orce (3 (ii Froude number = Preure orce Gravity orce (33 (iii Reynold number = Inertia orce Vicou orce (34 From the calculation the etimated eective diuivity D e = m / at the pipe exit. Note: (iv Schmidt number = Momentum diuivity Molecular diuivity / D e ( / 76 The um o molecular and eddy diuivity = total diuivity and = 0.34 i the average value o the Schmidt number. Conidering the molecular and momentum diuivity value or the and particle. Thi ratio being o mall implie that the molecular diuivity i higher relative to momentum diuivity or the particle. The average value o the Schmidt number or a pherical particle i 0.9 rom literature. Thi value may be accurate or ine ince they are maller and diue ater but in thi work medium and ize particle were conidered. Alo there could be ome variation that i in luid rheology uch a denity and vicoity along with particle ize etc. in the three region (ub-laminar tranition and turbulent core conidered wherea the Fick Equation or diuion that wa ued to etimate the molecular diuivity doe not incorporate thee change although the eect or eddie were accounted or. The aorementioned dimenionle number were obtained ater olving the momentum equation. The reult or the orce competition can be een in Table (4 5 and 6. Schmidt number wa determined and aumed contant throughout the tranport proce. Table 4. Friction actor or and along the axial ditance. t (hr 0 m 6m m 8 m 4 m

11 30 The Open Petroleum Engineering Journal 07 Volume 0 Sanni et al. (Table 4 contd... t (hr 0 m 6m m 8 m 4 m Table 5. Friction actor or water along the axial ditance. t (hr 0 m 6m m 8 m 4 m Table 6. Friction actor or oil along the axial ditance. t (hr 0 m 6m m 8 m 4 m RESULTS AND DISCUSSIONS The produced and and crude oil obtained rom experiment were compared with etimate o and and crude oil rom Doan et al. [6] Sanni et al. [3] model and the new three-phae model. In Table or a total o 0 run the quantity o produced oil calculated by the Doan et al. [6] Sanni et al. [3] model and the new three phae model compared avourably with the value obtained rom experimental data with the model giving high level o accuracy (that i over 99 % accuracy. However or the produced and in pound per thouand barrel the Doan et al. [6] and Sanni et al. [3] gave poor etimate with error o % while the new model gave better prediction with high preciion o over % or 0.3 % error. The reaon or the poor perormance o the Doan et al. [6] and the Sanni et al. [3] model relative to the newly developed model i the amount o aociated water accompanying the and phae. Baed on the analye it wa dicovered that or low water cut reervoir the amount o water i low hence the Sanni et al. [3] model i le prone to error when ued or and etimation. A the water cut in the reervoir luid tend to zero the new model reduce to the Sanni et al. [3] model. However or very low water cut reervoir the Doan et al. [6] and the Sanni et al. [3] can give good etimate o the amount o oil recovered rom the well but become more prone to error a the quantity o aociated water in the oil increae (Fig Eect o Reynold Number Reynold number help to characterize a low ytem and alo give inight to the ratio o the magnitude o inertia to vicou orce at the low condition. From the calculated Reynold number or and it i evident that almot all the and particle were in the turbulent region between the 0 and 6 m point. The region characterized by the low at the 0 m point how that the and particle were between the turbulent core and the tranition zone while beyond the 8 m point the particle were already in the laminar regime. Reynold number at or below 000 reveal that low i laminar Re >000 but le than 300 reveal that the low i in the tranition zone and Re > 300 how that the low i turbulent. In the contour plot o Fig. ( the Reynold number o the and phae or the irt our hour varied between and 3.4 rom the inlet down to the exit repectively although the value at each point wa contant between and 4 hour. Thi region lie between the dark blue (laminar region and red (laminar laminar ub-layer tranition zone and turbulent region region which are cloe to the pipe wall. It dropped igniicantly at the inlet probably becaue o the type o creen (coare creen the mixture wa in contact with between the 0 and 6 m point. Coare creen help to ieve out o the mixture the larget o and particle which are alo capable o orming a and cake around and on the creen urace over time thu reducing the inlux velocity low rate and preure. Dierent creen ize are integrated within uptream petroleum pipeline ranging rom very coare to coare medium ine and very ine creen baed on their meh ize and and inormation obtained rom the production/ormation zone. However rom the etimated Reynold number obtained at the 6 8 and 4 m point that i and 3.4. It i obviou that ubequent creen could alo be reponible or low reduction which then reulted in increaed preure drop hence

12 Mechanim or Controlling Sand-induced Corroion The Open Petroleum Engineering Journal 07 Volume 0 3 the low condition were altered ince the change in Reynold number rom point to point how that the to 4 m point hould be given pecial attention in order to avoid cae o low eizure. Between the and 8 m point a moving bed o and may be ormed however it continuou movement will caue tre corroion cracking o the pipe a the and grain may grind o ome metallic grain o the pipe along the pipe grain boundarie. For the 8 m and 4 m egment o the pipe a tationary bed may reult which in turn reduce the low area and impart ome momentum on the oil thu cauing oil to low with a higher velocity through the available pace above the and bed. Thi goe urther to imply that at ome critical condition oil recovery may till be evident owing to the inluence o the moving bed on the oil however here the bed height o the and particle become igniicant. 3.5 Exp Sanni et al. New model Doan et al Sand produced lb/mbbl Number o run Fig. (. Proile o experimental and model etimate o produced and at the well head. Reynold number Sand Reynold number Water Reynold number Oil Reynold number Axial ditance m Fig. (. Reynold number o and oil and water at dierent time along the axial ditance. A dicued or the and phae between and 4 hour the Reynold number o the oil phae wa 960 at the pipe inlet and lowet (8 at the exit; thi region lie between the dark blue laminar layer to the light blue turbulent core region. Here the change i mot igniicant between the 8 and 4 m point baed on the undercored reaon or the and phae in term o preure drop creen and and depoit ormation within the line between thoe point. At the 6

13 3 The Open Petroleum Engineering Journal 07 Volume 0 Sanni et al. 8 and 4 m point the calculated Re are and 8 repectively or the irt our hour. Although high Reynold number are deired the value at the inlet and 6 m point hould alo be checked becaue high turbulence begin at or above 4000 and i the low rate i ar too high it can reult in pipe hammering or knocking which could impart unbearable preure on the pipe wall thu reulting in pipe burt/rupture. Depite the degree o turbulence deired it hould be moderated uch that the Re i about hal thi value o that with the help o booter/pump it become ae to tranport the entrained and and water. Conidering all point rom the inlet down the exit ince Re i the ratio o inertia to vicou orce one can iner rom the etimated Reynold number that inertia orce (enuing rom the low velocitie dominate the vicou orce which tend to oppoe the movement o the reervoir luid; the inertia orce at the exit till how that the inertia orce are 8 time the magnitude o the vicou orce hence it i reaonable to till have oil recovered baed on the magnitude o the oil preure at the pipe exit. Furthermore depite the deire to have high inertia orce it i alo reaonable to conider equipment/pipe integrity at any low condition. The inertia orce urpa the vicou orce to a good meaure at the 0 and 6 m point which raie concern or pipe aety while at the outlet operation in the indutry gave report on preure drop and low anomalie that were regulated to prevent plugging and pigging operation. Furthermore it i recommended that the Re be maintained ar above the condition or critical low or enhanced oil recovery. For the water the etimated Reynold number wa een to decreae rom the inlet to the exit between and 4 h. It wa approximately and 6 at the and 4 m point repectively; thi region i characterized by the dark blue laminar layer to the purple turbulent core region. Although it i good to keep the Re high enough o a to keep the water phae upended in the lowing tream becaue at critical condition the Re being too low will caue water and depoited and to ret on the pipe wall which i unae or the pipe a corroion and pipe abraion may et in rom bed load tranport o the and that i i the depoited and orm a moving bed at the low condition. I a tationary bed reult it then mean partial or total plugging o the pipe may reult which will either conine the low to a region above the depoit or completely retrict low a the cae may be. Table 4-6 give the calculated riction actor or the and water and oil phae repectively. The riction actor eem to rie rom the pipe inlet to the exit or all three component although the riction actor o the and i highet while that o the oil phae i leat with that o the water phae being higher. It i evident that the denitie and phae velocitie o the dierent component have igniicant inluence on their riction actor. Furthermore the drop in low rate o the carrier luid and and water i alo reponible or the reduction in Reynold number or all component o the mixture rom the pipe inlet through to the exit. Fig. (3 i a plot o the variation o the riction actor o the three component within the irt our hour and along the axial ditance. The plot how that the riction actor increae along the axial ditance and i highet or the and phae that o water i next in magnitude while the oil phae ha the leat riction actor. Friction actor Axial ditance m Friction actor or and phae Friction actor or water phae Friction actor or oil phae Fig. (3. Friction actor or and oil and water along the axial ditance.

14 Mechanim or Controlling Sand-induced Corroion The Open Petroleum Engineering Journal 07 Volume 0 33 Reynold number o component Sand inertia to vicou orce Oil inertia orce to vicou orce water inertia orce to vicou orce Axial ditance m Fig. (4. Reynold number o component along the axial ditance. The Reynold number o the component a hown in Fig. (4. decreae along the axial ditance. Thi i a a reult o the reduced velocitie. A the velocitie o the component decreaed rom the pipe inlet to the exit correponding reduction can alo be een or the three component. However oil being the lightet o the three component howed the leat reduction in Reynold number while that o water wa higher with and having the lowet Reynold number along the pipe axi. Preure orce/gravity orce water preure to gravity orce Oil preure to gravity orce Sand preure to gravity orce Axial ditance m Fig. (5. Ratio o preure to gravity orce or oil and and water along the axial ditance. For the irt our hour the ratio o preure to gravity orce a hown in Fig. (5 in decreaing order o magnitude or the component i and water and oil. Thi i imply due to the act that thee orce are meaure o the concentration o the three component that i it i a a reult o the dierence in concentration o and oil and water rom point to point along the pipe axi.

15 34 The Open Petroleum Engineering Journal 07 Volume 0 Sanni et al. Froude number o component Sand Froude number Oil Froude number Water Froude number Axial ditance m Fig. (6. Froude number o oil and and water along the axial ditance. Fig. (6 give an illutration o the orce competition between inertia and gravity orce. Inertia orce o the three component o the mixture are unction o their velocitie while their gravity orce are meaure o the concentration ditribution o the three component in the mixture that i where velocity i highet inertia orce i maximized and where concentration i highet gravity orce i maximized and vice-vera. The Froude number o oil i highet next to it i that o water and that o and i lowet between 0-4 h o well production time. Thi goe urther to imply that conidering Fig. (5 and 6 in order to operate and maintain the pipe within reliable and ae low condition it i neceary to keep the inertia orce high by integrating a booter at ome point mid-way between the pipe terminal. Thi i o a to make up or the lot inertia orce thu controlling/reducing the and phae preure exerted by the agglomeration o and or clutering and or water molecule at critical point within the low ytem. Becaue toward the exit the drop in inertia orce tend toward the critical depoit velocity thu increaing the rictional orce in the pipeline. 4 Euler number o and Euler number o oil Euler number o water Euler number o component Axial ditance m Fig. (7. Ratio o preure to inertia orce or oil and and water along the axial ditance. In Fig. (7 The orce competition between the preure and inertia orce how that the critical point or controlling phae preure i the -8 m point beyond which preure orce begin to dominate the inertia orce o and and water which mut not ettle on the pipe wall i the pipe integrity mut be maintained/utained.

16 Mechanim or Controlling Sand-induced Corroion The Open Petroleum Engineering Journal 07 Volume 0 35 Sand Inertia orce per unit ma m Axial ditance m Sand phae preure orce per unit ma m - I V P g Fig. (8. Force ditribution o the and particle acro the pipe. For urther invetigation the model wa tuned in order to ee the eect o the undercored mechanim a the low become tratiied at lower Reynold number. Fig. (8 conirm the need to tep up the inertia orce (I againt the gravity orce (g and preure orce (P at Reynold number o 300 where the low i laminar that i higher Euler and lower Froude number are required to keep the tream lowing a a continuum or upenion a thi will alo help to reduce the tendency o having water and and conined to the pipe wall. Alo under thi condition the value o and gravitational or and preure orce are higher than the inertia or vicou orce (V o the carrier crude oil. Uing the Stuhmiller model [5] the interacial preure o the component were determined. The and crude oil and water denitie ued are and 000 kg/m 3 repectively. At the urace o a phere the normal orce exerted at the urace i at 90 o to the urace. The etimated interacial preure on hourly bai how that the interacial preure at the oil-water interace i higher than the interacial preure at the water-and interace and the preure between the and phae and the pipe wall which are in the range o kgm kgm - - and kgm - - repectively. Thi i due to their repective denitie and lowing velocitie under the low condition ee Fig. (9. The eae with which oil will rub or lide over water i higher than the rate o low o water over the and phae and rom the etimated preure it how that a the low condition become critical the and and water interaction may become detrimental to the pipe. However eort hould be made to keep the tream lowing at preure high enough to enhance oil-and interaction by taking advantage o the repulive orce between oil and water ince they do not mix thu lowering the oil-water interaction orce becaue rom the etimated interacial orce it i omewhat evident that the oil-and interaction orce may get wore toward the pipe exit. Interacial preure o component kgm Axial ditance m Pi (and Pi (oil Pi (water Fig. (9. Interacial preure o the component along the axial ditance.

17 36 The Open Petroleum Engineering Journal 07 Volume 0 Sanni et al. CONCLUSION The reult rom the imulation how that the model give good decription o the orce reponible or the low o a mixture o and crude oil and water through horizontal pipe in oil well. From the calculated orce one could ee at a glance that Euler number eemed to how igniicant variation beyond the 8 m point where the pipe integrity may be at take depending on the nature o the low regime and drag orce on the pipe wall. The Froude number o the three component howed igniicant variation rom the inlet to the exit o the pipe and a tated earlier the critical point or conideration during monitoring operation hould be the -8 m point beyond which the preure orce begin to compete avourably with/dominate the inertia orce. Furthermore in order to prevent and depoition in a petroleum pipeline the inertia orce imparted by the carrier oil mut eentially dominate the and phae preure and gravity orce. NOMENCLATURE Symbol Deignation Unit Letter A Cro-ectional area m g Gravitational acceleration m- P Oil phae preure kgm-- P k Kinematic preure kgm-- P Sand phae preure kgm-- P w Water phae preure kgm-- q Volume low rate o oil m3- q Volume low rate o and m3- q w Volume low rate o water m 3 - t Time hr or V m Volume o mixture m3 w o Oil velocity m- w Sand velocity m- w w Water velocity m- z Axial ditance m β Fluid-particle interaction coeicient kgm3- Δz Change in length m ε Oil concentration (volume raction - ϕ Supended and concentration (volume raction - σ Depoited and concentration (volume raction - ϕ Total and concentration (volume raction - θ Water concentration (volume raction - ρ Oil denity kg/m3 ρ Sand denity kg/m3 ρ w Water denity kg/m3 LIST OF ABBREVIATIONS BLPD = Barrel o liquid per day bbl/day BOPD = Barrel o oil per day bbl/day BSW = Bae ediment & water % Choke = Choke ize - FTP = Flowing tubing preure Pia Ga = Amount o ga produced c/d GOR = Ga oil ratio - GL rate = Ga-liquid rate c/day Pinj = Injection preure Pia PTB = Part per thouand barrel pptb

18 Mechanim or Controlling Sand-induced Corroion The Open Petroleum Engineering Journal 07 Volume 0 37 CONSENT FOR PUBLICATION Not applicable. CONFLICT OF INTEREST The author hereby declare that there i no conlict o interet o any ort a regard the publication o thi article a all contributor have been included with the ponor duly acknowledged. ACKNOWLEDGEMENTS The author wih to thank ADDAX oil Limited and Department o Petroleum Reource Nigeria Ltd or their contribution in making thi reearch work a ucce. Alo Covenant Univerity i appreciated or her ponorhip and upport in liaion with the company management at a time it wa neceary and while the work wa in progre. The author alo appreciate Samuel Sanni or carrying out the reearch and preparing the manucript Samuel Adeila or hi contribution and ueul uggetion Ambroe Anozie or hi contribution reviion and involvement in the mathematical imulation and Oluranti Agboola or reviing and editing the manucript. REFERENCES [] O.A. Adeyanju and L.O. Oyekunle "Hydrodynamic o oil-and-ga multiphae low in a near vertical well" Nigerian Annual Conerence and Exhibition 0pp. -7 Abuja Nigeria [ [] S. Berrone and M. Marro Space-Time Adaptive Simulation or Unteady Navier Stoke Problem. vol. 38. Computer and Fluid 009 pp [3] J.A. Boulanger and C.Y. Wong "Sand upenion depoition in horizontal low-concentration pipe low" Granul. Matter vol. 8 no. pp [ [4] K.W. Chu S.B. Kuang A.B. Yu and A. Vince Particle cale modelling o the multiphae low in a dene medium cyclone: Eect o luctuation o olid low rate. vol. 33. Mineral Engineering 0 pp [5] H. Davarzani M. Marcoux P. Coteeque and M. Quintard "Experimental meaurement o the eective diuion and thermodiuion coeicient o binary ga mixture in porou media" Chem. Eng. Sci. vol. 65 no. 8 pp [ [6] Q. Doan A. Farouq A. George and M. Oguztoreli "Sand depoition inide a horizontal well - A imulation approach" SPE J. vol. 39 pp [7] R.C. Givler and R.R. Mikataranian "Numerical imulation o luid-particle low: Geothermal drilling application" J. Fluid Eng. vol. 09 no. 3 pp [ [8] S. Horender and Y. Hardalupa Fluid-Particle Correlated Motion and Turbulent Energy Traner in a Two-Dimenional Particle-laden Flow. vol. 65. Chemical Engineering Science 00 pp [9] H. Jia and R. Dang "Development o contactle and Production Intrument" Open Petroleum Engineering Journal vol. 0 pp [ [0] S. Kawano A. Sei and M. Kunitake "Thixotropic Interparticle Interaction between Silica and non-ionic Polymer Particle Prepared by Static Diperion Polymerization" Polymer (Guild. vol. 5 no. 7 pp [ [] Y. Liu X. Liu and G. Li Numerical Invetigation on Hydrodynamic o Ga Binary Particle Flow Uing a Second-Order-Moment Turbulent Model. vol. 7. Acta Atronautica 0 pp [] H. Rahmati M. Jaarpour S. Azadbakht A. Nouri H. Vaziri D. Chan and Y. Xiao "Review o Sand Production Prediction Model" Journal o Petroleum Engineering vol. 03 pp [ [3] S.E. Sanni A.S. Olawale and S.S. Adeila "Modeling o and and crude oil low in horizontal pipe during crude oil tranportation" J. Eng. vol. 05 pp [ [4] S.E. Sanni Modelling o Sand Entrainment and Depoit in Horizontal Oil Tranport A.S. Olawale & S.S. Adeila Ed. Deutchland Germany: Verlag Scholar Pre 06 pp [5] J.H. Stuhmiller "The Inluence o Interacial Preure Force on the Character o Two Phae Flow Model Equation" Int. J. Multiph. Flow vol. 3 pp [

19 38 The Open Petroleum Engineering Journal 07 Volume 0 Sanni et al. [6] B. Wang "Interace interaction in a turbulent vertical channel low laden with heavy particle. part I: Numerical method and particle diperion propertie" Int. J. Heat Ma Traner vol. 53 pp [ [7] S.Z. Zhou S. Zhang Z.P. Lv and L. Qin "Reearch and imulation o olid-conveyance law o the hale haker" Open Pet. Eng. J. vol [8] Received March acceed 07 Sanni et al. Thi i an open acce article ditributed under the term o the Creative Common Attribution 4.0 International Public Licene (CC-BY 4.0 a copy o which i available at: Thi licene permit unretricted ue ditribution and reproduction in any medium provided the original author and ource are credited.