IndexINDEX:1Discussion2Nomenclature3References4Standard Separator Sizes as per API5Separator sizing with mist extractor5ATwo Phase (Gas - Oil) Vertical Separator as per API 12J5BTwo Phase (Gas - Oil) Horizontal Separator as per API 12J5CThree Phase (Gas - Oil - Water) Vertical Separator as per API 12J5DThree Phase (Gas - Oil - Water) Horizontal Separator as per API 12J6Separator sizing without mist extractor6ATwo Phase (Gas - Oil) Vertical Separator As per Petroleum and Gas Field Processing6BTwo Phase (Gas - Oil) Horizontal Separator as per Petroleum and Gas Field Processing6CThree Phase (Gas - Oil - Water) Vertical Separator as per Petroleum and Gas Field Processing6DThree Phase (Gas - Oil - Water) Horizontal Separator as per Petroleum and Gas Field ProcessingPrepared by:Ajay S. SatputeSr. Process EngineerRamboll Consulting Engineering, Qatar

DiscussionNomenclatureReferencesStandard Separator Sizes as per APITwo Phase (Gas - Oil) Vertical Separator as per API 12JTwo Phase (Gas - Oil) Horizontal Separator as per API 12JThree Phase (Gas - Oil - Water) Vertical Separator as per API 12JThree Phase (Gas - Oil - Water) Horizontal Separator as per API 12JTwo Phase (Gas - Oil) Vertical Separator As per Petroleum and Gas Field ProcessingTwo Phase (Gas - Oil) Horizontal Separator as per Petroleum and Gas Field ProcessingThree Phase (Gas - Oil - Water) Vertical Separator as per Petroleum and Gas Field ProcessingThree Phase (Gas - Oil - Water) Horizontal Separator as per Petroleum and Gas Field ProcessingINDEX:

DiscussionDISCUSSIONINDEXThis spreadsheet provides an easy and simple approach to (2/3 phase and vertical/horizontal) separator sizing. Formulae and references are also provided for process engineers to edit/duplicate this work (file is NOT password protected).There is as much art as there is science to properly design a separator. Three main factors should be considered in separator sizing: 1) vapor capacity, 2) Liquid capacity, and 3) operability. The vapor capacity will determine the cross-sectional area necessary for gravitational forces to remove the liquid from the vapor. The liquid capacity is typically set by determining the volume required to provide adequate residence time to de-gas the liquid or allow immiscible liquid phases to separate. Operability issues include the separators ability to deal with solids if present, unsteady flow/liquid slugs, turndown, etc. Finally, the optimal design will usually result in an aspect ratio that satisfies these requirements in a vessel of reasonable cost. These factors often result in an iterative approach to the calculations.Two sets of calculations are carried out here. 1. Separators with Mist Extractors and 2. Separators without Mist ExtractorsSeveral useful guidelines for separator design are provided below;Momentum & Velocity criteria for nozzles (Source: DEP 31.22.05.12 - Gen.- 2008)Inlet NozzleMomentum or Velocity LimitNo InternalMax. Momentum, m V2m 1400 PaHalf open pipeMax. Momentum, m V2m 2100 PaSchoepentoeter used as inlet deviceMax. Momentum, m V2m 8000 PaGas outlet NozzleMax. Momentum, g V2g,out 4500 PaLiquid outlet NozzleMaximum velocity, 1 m/sSelection guideline for separator typesSystem CharacteristicsType of SeparatorLarge vapour, less liquid Load (by volume)VerticalLarge liquid, less vapour Load (by volume)HorizontalLarge vapour, large liquid Load (by volume)HorizontalLiquid-liquid separationHorizontalLiquid-solid separationVerticalLevel setting in the separatorLevel typeLevel settingLevel Alarm High High (LAHH)30 60 seconds or 200 mm whichever is greaterLevel Alarm High (LAH)30 60 seconds or 200 mm whichever is greaterNormal Alarm Level (NAL)60% of horizontal separatorLevel Alarm Low (LAL)30 60 seconds or 200 mm whichever is greaterLevel Alarm Low Low (LALL)30 60 seconds or 200 mm whichever is greater Should be at least 200 mm above the vessel bottom or maximum interface levelTypical K factors for the sizing of wire mesh demisters (Source: IPS-E-PR-880, 1997)Separator typeK factor (m/s)Horizontal (with vertical pad)0.122 to 0.152Spherical0.061 to 0.107Vertical or horizontal (with horizontal pad)0.055 to 0.107At atmospheric pressure0.107At 2100 kPa0.101At 4100 kPa0.091At 6200 kPa0.082At 10300 kPa0.064Wet steam0.076Most vapours under vacuum0.061Salt and caustic evaporators0.046

INDEX

NomenclatureNOMENCLATUREINDEXAtotal cross sectional area of the separator.Awcross sectional area of the separator occupied by water, ft2Aocross sectional area of the separator occupied by oil, ft2Agcross sectional area of the separator occupied by gas, ft2CDdrag coefficientdvessel internal diameter, in.dmbubble or drop diameter, mDvessel diameter, fthliquid height, in.hggas-phase space height, in.hooil pad height, in.hwwater pad height, in.Kmesh capacity factor, ft/secLeff or Leffective length of the vessel where separation occurs, ftLss or Lsseam-to-seam vessel length, ftNLLnormal liquid level, %Poperating pressure, psiaQccontinuous liquid-phase flow rate, bbl/dayQggas flow rate, MMSCFD or ft3/sQooil flow rate, bbl/dayW or Qwwater flow rate, bbl/dayReReynolds numberToperating temperature, RVliquid settling volumeVamax. allowable velocity through secondary separation sectionVmvelocity of the mixture, m/sZgas compressibilityccontinuous phase dynamic viscosity, cpwwater dynamic viscosity, cPdensity, lbm/ft3ggas density, lbm/ft3lliquid density, lbm/ft3ooil density, lbm/ft3mmean density of mixture, kg/m3wwater density, lbm/ft3

INDEX

ReferencesREFERENCESINDEXhttp://en.citizendium.org/wiki/Vapor-liquid_separatorAPI 12J, Specification for oil and gas separators, 1989http://petrowiki.org/Separator_sizinghttp://www.cheresources.com/invision/topic/11856-selecting-vertical-separator-ld-ratio/Petroleum and Gas Field Processing - Hussein K. Abdel-Aal, Mohamed Aggour, M. A. Fahimhttp://books.google.com.qa/books?id=BZOPlA-SmMUC&pg=PA97&lpg=PA97&dq=%22three+phase%22+separator+L/D+ratio+%22GPSA%22&source=bl&ots=u979BoWCxd&sig=p13fCbqS52y7bE3eGRDtfj7nGq0&hl=en&sa=X&ei=s9dMVJHiHKvcywO4tIK4BQ&redir_esc=y#v=onepage&q=%22three%20phase%22%20separator%20L%2FD%20ratio%20%22GPSA%22&f=falsehttp://www.cheresources.com/invision/topic/17158-three-phase-separator-design-suggestion-needed/http://en.citizendium.org/wiki/Vapor-liquid_separatorhttp://www.chemicalforums.com/index.php?topic=8913.0http://www.chemicalforums.com/index.php?topic=9252.0http://www.cheresources.com/invision/topic/41-sizing-a-flash-tank-or-vapor-liquid-separator/http://www.eng-tips.com/faqs.cfm?fid=1153http://process-designs.com/http://www.razifar.com/cariboost_files/Design_20Two_20Phase_20Separators_20Within_20the_20Right_20Limits.pdfhttp://en.wikipedia.org/wiki/Souders%E2%80%93Brown_equationhttp://books.google.com.qa/books?id=lpA83iVcaGYC&pg=PA159&lpg=PA159&dq=Kh+%3D+1.25+Kv+separator&source=bl&ots=fV8ewKHkag&sig=q70X8-xfxPnk9MBMHgaEFwLhIhU&hl=en&sa=X&ei=M-NVVPepM4XWPfaLgYAI&redir_esc=y#v=onepage&q=Kh%20%3D%201.25%20Kv%20separator&f=falseIPS-E-PR-880, 1997GPSA - Engineering Data Book (12th Ed)

http://en.citizendium.org/wiki/Vapor-liquid_separatorhttp://petrowiki.org/Separator_sizinghttp://www.cheresources.com/invision/topic/11856-selecting-vertical-separator-ld-ratio/http://en.citizendium.org/wiki/Vapor-liquid_separatorhttp://www.chemicalforums.com/index.php?topic=8913.0http://www.chemicalforums.com/index.php?topic=9252.0http://www.cheresources.com/invision/topic/41-sizing-a-flash-tank-or-vapor-liquid-separator/http://www.eng-tips.com/faqs.cfm?fid=1153http://books.google.com.qa/books?id=BZOPlA-SmMUC&pg=PA97&lpg=PA97&dq=%22three+phase%22+separator+L/D+ratio+%22GPSA%22&source=bl&ots=u979BoWCxd&sig=p13fCbqS52y7bE3eGRDtfj7nGq0&hl=en&sa=X&ei=s9dMVJHiHKvcywO4tIK4BQ&redir_esc=y#v=onepage&q=%22three%20phase%22%20separator%20L%2FD%20ratio%20%22GPSA%22&f=falsehttp://process-designs.com/INDEX

Std. Sep. sizesSTANDARD SEPARATOR SIZES AS PER APIINDEXD [in] x H or L [ft]12 in x 5 ft12 in x 7 ft12 in x 10 ft16 in x 5 ft16 in x 7 ft16 in x 10 ft20 in x 5 ft20 in x 7 ft20 in x 10 ft24 in x 5 ft24 in x 7 ft24 in x 10 ft30 in x 5 ft30 in x 7 ft30 in x 10 ft36 in x 5 ft36 in x 7 ft36 in x 10 ft36 in x 15 ft42 in x 7 ft42 in x 10 ft42 in x 15 ft48 in x 7 ft48 in x 10 ft48 in x 15 ft54 in x 7 ft54 in x 10 ft54 in x 15 ft60 in x 7 ft60 in x 10 ft60 in x 15 ft

INDEX

5AINDEXTwo Phase (Gas - Oil) Vertical separator: As per API 12JINPUT PARAMETERSQg25mmscfdGas rateYellow boxes are input boxes.Qo3000bbl/dOil rateSCHEMATIC0.70Gas specific gravity'o40oAPIOil densityo0.83Oil specific gravityP814.5psiaOperating pressureT'80oFOperating temperatureT540oROperating temperatureMW20.3lb/lbmoleMolecular weightt1minutesRetention time (Refer Table 2)Z0.84Gas compressibilityg0.013cPGas viscosityH10ftShell height (assume)K0.30ft/sRefer Table 1NLL30%Normal liquid level (assume)CALCULATIONSEQUATIONSTABLESStep 1:Determine gas and oil propertiesg3.4lb/ft3Gas operating densityTable 1o51.5lb/ft3Oil operating densityHeight, ftTypical K factor range50.12 to 0.24Step 2:100.18 to 0.35Va1.13ft/sQg,a4.55ft3/sActual volume flow of gasTable 2Ag,min4.03ft2Minimum gas flow areaOil GravitiesRetention time, minutes (Typical)Dmin27inMinimum ID of separatorAbove 35 oAPI120 to 30 oAPI1 to 2Dselected30inNext larger and appropriate size10 to 20 oAPI2 to 4H10ftShell heightH / D4.0unitlessRefer Note 4Step 3:V2.6bblLiquid volume (excluding bottom head)W3777bpdLiquid capacity of separator should be more than 3000 bpd (input value)NOTES1. The maximum allowable superficial velocity calculated from the above factors is for separators normally having a wire mesh mist extractor. This rate should allow all liquid droplets larger than 10 microns to settle out of gas.2. Additional resource for K factor from GPSA Engineering Data Book:Pressure, bargK factor, m/sAdjustment of K factor for pressure00.11Pressure, psig% of Design value70.11Atm.100210.1015090420.0930085630.08600801050.07115075GPSA Notes:1. K = 0.107 at a gauge pressure of 7 bar. Subtract 0.003 for every 7 bar above a gauge pressure of 7 bar.2. For glycol or amine solutions, multiply above K values by 0.6 - 0.8.3. Typically use one-half of the above K values for approximate sizing of vertical separators without mesh pads.4. For compressor suction scrubbers and expander inlet separators, multiply K by 0.7 - 0.8.3. Additional resource for retention times from gas Conditioning and Processing, Volume 2.Natural gas-oil1 to 3 minutesLean oil surge tanks10 to 15 minutesFractionation feed surge tanks8 to 15 minutesRefrigerant surge tanks4 to 7 minutesRefrigerant econonomizers2 to 3 minutes4. As per GPSA, typical vertical H/D ratios are normally in the 2 to 4 range.

Manipulate NLL and H to get appropriate W.Souders-Brown equationINDEX

5BINDEXTwo Phase (Gas - Oil) Horizontal Separator: As per API 12JINPUT PARAMETERSSCHEMATICQg25mmscfdGas rateYellow boxes are input boxes.Qo3000bbl/dOil rate0.70Gas specific gravity'o40oAPIOil densityo0.83Oil specific gravityP814.5psiaOperating pressureT'80oFOperating temperatureT540oROperating temperatureMW20.3lb/lbmoleMolecular weightt1minutesRetention time (Refer Table 2)Z0.84Gas compressibilityg0.012cPGas viscosityK0.5ft/sRefer Table 1NLL30%Normal liquid level (assume)L10ftShell Length (assume)CALCULATIONSEQUATIONSTABLESStep 1:Determine gas and oil propertiesg3.4lb/ft3Gas operating densityTable 1o51.5lb/ft3Oil operating densityLength, ftTypical K factor range, ft/s100.4 to 0.5Step 2:Other Lengths0.4 to 0.5 x (L/10)0.56Va1.881ft/sQg,a4.55ft3/sActual volume flow of gasTable 2Ag,min2.42ft2Minimum gas flow areaOil GravitiesRetention time, minutes (Typical)Dmin4inAssumeAbove 35 oAPI1Ag,min2.42ft220 to 30 oAPI1 to 2Error0.0010 to 20 oAPI2 to 4Dselected30inNext larger and appropriate sizeL10ftShell lengthL / D4.0unitlessRefer Note 4Step 3:V3bblLiquid volume (excluding bottom head)W3644bpdLiquid capacity of separator should be more than 3000 bpd (input value)NOTES1. The maximum allowable superficial velocity calculated from the above factors is for separators normally having a wire mesh mist extractor. This rate should allow all liquid droplets larger than 10 microns to settle out of gas.2. Additional resource for K factor from GPSA Engineering Data Book:Pressure, bargK factor, m/sAdjustment of K factor for pressure00.11Pressure, psig% of Design value70.11Atm.100210.1015090420.0930085630.08600801050.07115075GPSA Notes:1. K = 0.107 at a gauge pressure of 7 bar. Subtract 0.003 for every 7 bar above a gauge pressure of 7 bar.2. For glycol or amine solutions, multiply above K values by 0.6 - 0.8.3. For compressor suction scrubbers and expander inlet separators, multiply K by 0.7 - 0.8.3. Additional resource for retention times from gas Conditioning and Processing, Volume2.Natural gas-oil1 to 3 minutesLean oil surge tanks10 to 15 minutesFractionation feed surge tanks8 to 15 minutesRefrigerant surge tanks4 to 7 minutesRefrigerant econonomizers2 to 3 minutes4. As per GPSA, typical horizontal L/D ratios are normally in the 2.5 to 5 range.

Souders-Brown equationManipulate NLL and L to get appropriate W.INDEX

5CINDEXThree Phase (Gas - Oil - Water) Horizontal Separator: As per API 12JINPUT PARAMETERSQg8mmscfdGas rateYellow boxes are input boxes.SCHEMATICQo8000bbl/dOil rateQw3000bbl/dWater rate0.70Gas specific gravity'o40oAPIOil densityo0.83Oil specific gravityP250psiaOperating pressureT'60oFOperating temperatureT520oROperating temperatureMW20.3lb/lbmoleMolecular weightH18ftShell height (assume)to5minutesOil retention time (Refer Table 2)tw5minutesWater retention time (Refer Table 2)Z0.84Gas compressibilityg0.013cPGas viscosityK0.35ft/sRefer Table 1NLL50%Normal liquid level (assume)CALCULATIONSEQUATIONSTABLESStep 1:Determine gas and oil propertiesg1.1lb/ft3Gas operating densityTable 1o51.5lb/ft3Oil operating densityHeight, ftTypical K factor range, ft/s50.12 to 0.24Step 2:100.18 to 0.35Va2.4ft/sQg,a4.58ft3/sActual volume flow of gasTable 2Ag,min1.92ft2Minimum gas flow areaOil GravitiesRetention time, minutes (Typical)Dmin19inAssumeAbove 35 oAPI3 to 5Dselected96inNext larger (than Dmin) and appropriate sizeBelow 35 oAPIH18ftShell height100+ oF5 to 10H / D2.3unitlessRefer Note 480+ oF10 to 2060+ oF20 to 30Step 3:V81bblLiquid volume (excluding bottom head)W11602bpdLiquid capacity of separator should be more than 11000 bpd (input value)NOTES1. The maximum allowable superficial velocity calculated from the above factors is for separators normally having a wire mesh mist extractor. This rate should allow all liquid droplets larger than 10 microns to settle out of gas.2. Additional resource for K factor from GPSA Engineering Data Book:Pressure, bargK factor, m/sAdjustment of K factor for pressure00.11Pressure, psig% of Design value70.11Atm.100210.1015090420.0930085630.08600801050.07115075GPSA Notes:1. K = 0.107 at a gauge pressure of 7 bar. Subtract 0.003 for every 7 bar above a gauge pressure of 7 bar.2. For glycol or amine solutions, multiply above K values by 0.6 - 0.83. Typically use one-half of the above K values for approximate sizing of vertical separators without mesh pads4. For compressor suction scrubbers and expander inlet separators, multiply K by 0.7 - 0.83. Additional resource for retention times from gas Conditioning and Processing, Volume2.Natural gas-oil1 to 3 minutesLean oil surge tanks10 to 15 minutesFractionation feed surge tanks8 to 15 minutesRefrigerant surge tanks4 to 7 minutesRefrigerant econonomizers2 to 3 minutes4. As per GPSA, typical horizontal H/D ratios are normally in the 2 to 4 range.

Souders-Brown equationManipulate NLL, D and H to get appropriate W.INDEX

5DINDEXThree Phase (Gas - Oil) Horizontal Separator: As per API 12JINPUT PARAMETERSQg8mmscfdGas rateYellow boxes are input boxes.SCHEMATICQo8000bbl/dOil rateQw3000bbl/dWater rate0.70Gas specific gravity'o40oAPIOil densityo0.83Oil specific gravityP250psiaOperating pressureT'60oFOperating temperatureT520oROperating temperatureMW20.3lb/lbmoleMolecular weightL18ftShell Length (assume)to5minutesOil retention time (Refer Table 2)tw5minutesWater retention time (Refer Table 2)Z0.84Gas compressibilityg0.013cPGas viscosityK0.35ft/sRefer Table 1NLL50%Normal liquid level (assume)CALCULATIONSEQUATIONSTABLESStep 1:Determine gas and oil propertiesg1.1lb/ft3Gas operating densityTable 1o51.5lb/ft3Oil operating densityLength, ftTypical K factor range, ft/s100.4 to 0.5Step 2:Other Lengths0.4 to 0.5 x (L/10)0.56Va2.388ft/sQg,a4.58ft3/sActual volume flow of gasTable 2Ag,min1.92ft2Minimum gas flow areaOil GravitiesRetention time, minutes (Typical)Dmin2.4inAssumeAbove 35 oAPI3 to 5Ag,min1.92ft2Below 35 oAPIError0.00100+ oF5 to 10Dselected78inNext larger (than Dmin) and appropriate size80+ oF10 to 20L18ftShell length60+ oF20 to 30L / D2.8unitlessRefer Note 4Step 3:V77bblLiquid volume (excluding bottom head)W11036bpdLiquid capacity of separator should be more than 11000 bpd (input value)NOTES1. The maximum allowable superficial velocity calculated from the above factors is for separators normally having a wire mesh mist extractor. This rate should allow all liquid droplets larger than 10 microns to settle out of gas.2. Additional resource for K factor from GPSA Engineering Data Book:Pressure, bargK factor, m/sAdjustment of K factor for pressure00.11Pressure, psig% of Design value70.11Atm.100210.1015090420.0930085630.08600801050.07115075GPSA Notes:1. K = 0.107 at a gauge pressure of 7 bar. Subtract 0.003 for every 7 bar above a gauge pressure of 7 bar.2. For glycol or amine solutions, multiply above K values by 0.6 - 0.83. For compressor suction scrubbers and expander inlet separators, multiply K by 0.7 - 0.83. Additional resource for retention times from gas Conditioning and Processing, Volume2.Natural gas-oil1 to 3 minutesLean oil surge tanks10 to 15 minutesFractionation feed surge tanks8 to 15 minutesRefrigerant surge tanks4 to 7 minutesRefrigerant econonomizers2 to 3 minutes4. As per GPSA, typical horizontal L/D ratios are normally in the 2.5 to 5 range.

Souders-Brown equationManipulate NLL, D and L to get appropriate W.INDEX

6AINDEXTwo Phase (Gas - Oil) Vertical Separator: As per "Petroleum and Gas Field Processing - Hussein K. Abdel-Aal, Mohamed Aggour, M. A. Fahim"INPUT PARAMETERSSCHEMATICQg15mmscfdGas rateYellow boxes are input boxes.Qo3000bbl/dOil rate0.6Gas specific gravity'o35.0oAPIOil densityo0.85Oil specific gravityP985psiaOperating pressureT'60oFOperating temperatureT520oROperating temperaturet3minutesRetention time (Refer Table 1)Z0.84Gas compressibilityg0.013cPGas viscositydm100MicronSmallest oil droplet size to be removedCALCULATIONSEQUATIONSStep 1:Determine gas and oil propertiesg3.7lb/ft3Gas operating densityo53.0lb/ft3Oil operating densityStep 2:Determine CdCd1.13AssumeDrag coefficientu0.41ft/sSettling velocity of oil dropletRe56Reynolds no.Cd1.16Error0.00Use goal seek to get error zero, by changing asssumed CdStep 3:Check for gas capacity constraintD2974in2Dmin31.2inMinimum allowable vessel diameter for separation of oil droplets down to 100 micronStep 4:Check for liquid capacity constraintD2H77085Try different combinations of D.TABLE 1D, inH, inLs, ftSR3085.713.55.43659.511.33.84243.710.53.04833.510.12.55426.410.02.2TABLE 2 (Ref. API 12J)6021.410.12.0Oil GravitiesRetention time, minutes (Typical)6617.710.31.9Above 35 oAPI17214.910.61.820 to 30 oAPI1 to 27812.710.91.710 to 20 oAPI2 to 48410.911.21.6909.511.61.6Ls11.3ftSeam to seam length (select from Table 1)SR3.8Slenderness ratio (typical value 3 to 4) (select from Table 1)D36.0inSeparator diameter (select from Table 1)NOTES1. As per GPSA, typical vertical H/D ratios are normally in the 2 to 4 range.

Click meH = Height of oil columnINDEX

6BINDEXTwo Phase (Gas - Oil) Horizontal Separator: As per "Petroleum and Gas Field Processing - Hussein K. Abdel-Aal, Mohamed Aggour, M. A. Fahim"INPUT PARAMETERSQg15mmscfdGas rateYellow boxes are input boxes.SCHEMATICQo3000bbl/dOil rate0.6Gas specific gravity'o35.0oAPIOil densityo0.85Oil specific gravityP985psiaOperating pressureT'60oFOperating temperatureT520oROperating temperaturet3minutesRetention time (Refer Table 2)Z0.84Gas compressibilityg0.013cPGas viscositydm100MicronSmallest oil droplet size to be removedNLL50%Normal Liquid LevelCALCULATIONSEQUATIONSStep 1:Determine gas and oil propertiesg3.7lb/ft3Gas operating densityo53.0lb/ft3Oil operating densityStep 2:Determine CdCd1.2AssumeDrag coefficientu0.40ft/sSettling velocity of oil dropletRe55Reynolds no.Cd1.19Error0.00Use goal seek to get error zero, by changing asssumed CdStep 3:Check for gas capacity constraintLD83in.ftStep 4:Check for liquid capacity constraintD2L12852in2.ftTry different combinations of D.TABLE 1D, inLg, ftLs, ft (gas)Lo, ftLs, ft (oil)Governing caseSR = 12 ls (oil or gas)/D613.8514.35357.00476.0Liquid Capacity952.00126.937.9389.25119.0Liquid Capacity119.00243.465.4622.3129.8Liquid Capacity14.88TABLE 2 (Ref. API 12J)302.775.2714.2819.0Liquid Capacity7.62Oil GravitiesRetention time, minutes (Typical)362.315.319.9212.4Liquid Capacity4.14Above 35 oAPI1421.985.487.299.8Liquid Capacity2.8020 to 30 oAPI1 to 2481.735.735.588.1Liquid Capacity2.0210 to 20 oAPI2 to 4541.546.044.416.9Liquid Capacity1.53601.396.393.576.1Gas capacity1.28661.266.762.955.5Gas capacity1.23721.157.152.485.0Gas capacity1.19Ls12.4ftSeam to seam length (select from Table 1)SR4.1Slenderness ratio (typical value 3 to 5) (select from Table 1)D36inSeparator diameter (select from Table 1)NOTES1. As per GPSA, typical horizontal L/D ratios are normally in the 2.5 to 5 range.2. If D>30", Ls = 2.5 + Lo; Else, Ls = (4/3)*Lo Ref. http://process-designs.com/separators_and_scrubbers/separators_and_scrubbers.jsp

Click meClick meINDEX

6CINDEXThree Phase (Gas - Oil - Water) Vertical Separator: As per "Petroleum and Gas Field Processing - Hussein K. Abdel-Aal, Mohamed Aggour, M. A. Fahim"INPUT PARAMETERSQg8mmscfdGas rateYellow boxes are input boxes.SCHEMATICQo8000bbl/dOil rateQw3000bbl/dWater rate'o27.6oAPIOil densityo0.89Oil specific gravityo20cPOil viscosityw1.04Water specific gravity0.65Gas specific gravityZ0.89Gas compressibilityP250psiaOperating pressureT'95oFOperating temperatureT555oROperating temperaturetw10minutesWater retention time (Refer Table 2)to15minutesOil retention time (Refer Table 2)g0.013cPGas viscositydm,w500MicronSmallest water droplet size to be removeddm,o100MicronSmallest oil droplet size to be removedCALCULATIONSEQUATIONSStep 1:Determine gas and oil propertiesg0.89lb/ft3Gas operating densityo55.5lb/ft3Oil operating densityStep 2:Determine CdCd2.07AssumeDrag coefficientu0.65ft/sSettling velocity of oil dropletRe22Reynolds no.Cd2.09Error0.00Use goal seek to get error zero, by changing asssumed CdStep 3:Determine minimum diameter for water droplet settlingD2min28428in2Dmin168.6inStep 4:Check for gas capacity constraintD2min1475in2Dmin38.4inDmin168.6inLarger of Step 2 and 3 valuesStep 5:Check for liquid capacity constraintD2(Ho + Hw)1286400in3Try different combinations of D.TABLE 1TABLE 2 (Ref. API 12J)D, inHo + Hw, inLs, ftSR = 12 Ls / DOil GravitiesRetention time, minutes (Typical)165025425.1318.8Above 35 oAPI3 to 5203216274.3164.6Below 35 oAPI242233192.496.2100+ oF5 to 10301429125.450.280+ oF10 to 203699389.029.760+ oF20 to 304272967.619.34855853.913.55444144.69.96035738.17.61208920.82.11327420.51.9Ls20.8ftSeam to seam length (select from table 1)SR2.1Slenderness ratio (typical value 1.5 to 3) (select from Table 1)D120.0inSeparator diameter (select from Table 1)Qg86mmscfdCalculated gas capacity for selected L & D (Should be more than 8 MMSCFD - input value)NOTES1. As per GPSA, typical vertical H/D ratios are normally in the 2 to 4 range.

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6DINDEXThree Phase (Gas - Oil - Water) Horizontal Separator: As per "Petroleum and Gas Field Processing - Hussein K. Abdel-Aal, Mohamed Aggour, M. A. Fahim"INPUT PARAMETERSQg8mmscfdGas rateYellow boxes are input boxes.SCHEMATICQo8000bbl/dOil rateQw3000bbl/dWater rate'o27.5oAPIOil densityo0.89Oil specific gravityo20cPOil viscosityw1.04Water specific gravity0.65Gas specific gravityZ0.89Gas compressibilityP250psiaOperating pressureT'95oFOperating temperatureT555oROperating temperaturetw10minutesWater retention time (Refer Table 2)to15minutesOil retention time (Refer Table 2)g0.013cPGas viscositydm,w500MicronSmallest water droplet size to be removeddm,o100MicronSmallest oil droplet size to be removedNLL50%Normal liquid level due to oil and waterCALCULATIONSEQUATIONSStep 1:Determine gas and oil propertiesg0.89lb/ft3Gas operating densityo55.5lb/ft3Oil operating densityStep 2:Determine CdCd2.07AssumeDrag coefficientu0.65ft/sSettling velocity of oil dropletRe22Reynolds no.Cd2.09Error0.00Use goal seek to get error zero, by changing asssumed CdStep 3:Determine minimum diameter for water droplet settlingHo,max36.0inAw / A0.10Ao + Aw = NLL * AHo / D0.315AssumeAw / A0.13Error0.00Use goal seek to get error zero, by changing asssumed Ho/DDmax114inMaximum allowable vessel diameterStep 4:Check for gas capacity constraintDL122in.ftStep 4:Check for liquid capacity constraintD2L214350in2ftTry different combinations of D (smaller than Dmax).TABLE 1D, inL (gas), ftLs (gas)= L + D/12, ftL, ftLs (liquid)= 4 L/3, ftGoverning caseSR = L / (D/12)1210.211.21488.51984.7Liquid Capacity1984.7TABLE 2 (Ref. API 12J)245.17.1372.1496.2Liquid Capacity248.1Oil GravitiesRetention time, minutes (Typical)304.16.6238.2317.6Liquid Capacity127.0Above 35 oAPI3 to 5363.46.4165.4220.5Liquid Capacity73.5Below 35 oAPI661.97.449.265.6Liquid Capacity11.9100+ oF5 to 10721.77.741.355.1Liquid Capacity9.280+ oF10 to 20781.68.135.247.0Liquid Capacity7.260+ oF20 to 30841.58.530.440.5Liquid Capacity5.8901.48.926.535.3Liquid Capacity4.7961.39.323.331.0Liquid Capacity3.91021.29.720.627.5Liquid Capacity3.2Ls35.3ftSeam to seam length (select from Table 1)SR4.7Slenderness ratio (typical value 3 to 5) (select from Table 1)D90.0inSeparator diameter (select from Table 1)L26.5ftEffective length of the separatorQg156mmscfdCalculated gas capacity for selected L & D (Should be more than 8 MMSCFD - input value)NOTES1. As per GPSA, typical horizontal L/D ratios are normally in the 2.5 to 5 range.

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