Assessment of Oil Reservoir Properties Empirical Correlations Salem O. Baarimah1, Mohamed Mustafa2,Hamid Khattab3,Mahmoud Tantawy and Ahmed A.

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1 Assessment of Oil Reservoir Properties Empirical Correlations 4 Salem O. Baarimah1, Mohamed Mustafa2,Hamid Khattab3,Mahmoud Tantawy and Ahmed A. Gawish5 1,2,3,4,5 Petroleum Engineering Department,Suez University, Egypt Abstract Reservoir fluid properties such as oil bubble point pressure, oil formation volume factor, solution gas-oil ratio, gas formation volume factor, and gas and oil viscosities are very important in reservoir engineering computations. Perfectly, these properties should be obtained from actual laboratory measurements on samples collected from the bottom of the wellbore or at the surface. Quite often, however, these measurements are either not available, or very costly to obtain. For these reasons, it is necessary for the petroleum engineer to find a accurate, quick and reliable method for predicting the reservoir fluid properties.therefore, the concept of numerical correlation equations has been proposed to the petroleum industry to alleviate all difficulties in reservoir fluid properties determination.for this study, 63 published black oil empirical correlations for oil bubble point pressure and oil formation volume factorwere collected and summarized from 1946 till now in chronological order.a huge database of crude oil properties wereused to evaluate these correlations against whole range of API gravity and each class of API gravity. Keywords Reservoir fluid properties;empirical correlations;oil bubble point pressure; oil formation volume factor; Assessment. I. INTRODUCTION Reservoir fluid properties are very important physical properties that control the flow of oil through porous media and pipes. They used comprehensively in most of petroleum engineering applications such as drilling engineering, reservoir engineering, and production engineering. Accurate reservoir fluid properties are very important in reservoir engineering computations and a requirement for all types of petroleum calculations such as determination of initial hydrocarbons in place, optimum production schemes, ultimate hydrocarbon recovery, design of fluid handling equipment, and enhanced oil recovery methods. Actually, the reservoir fluid properties depend on pressure, temperature, and chemical compositions. For the development of a correlation, geological condition is considered important because the chemical composition of crude oil differs from region to region. For this reason, it is difficult to obtain the same accurate results through empirical correlations for different oil samples having different physical and chemical characteristics. Engineers should be modified these correlations for their application by recalculating the correlation constants for the region of interest. The purposeof this work is to study the performance of oil bubble point pressure and oil formation volume factor models available inthe literature, based on data sets collected from different published literature papers and PVT reports from different oil fields in the Saudi Arabia and Yemen. II. LITERATURE REVIEW The history of reservoir fluid properties correlation equations in the petroleum industry started more than five decades ago. Several reliable empirical correlations for calculating the reservoir fluid properties such as crude oil viscosity, oil formation volume factor, oil bubble point pressure, solution gas-oil ratio, gas formation volume factor and isothermal compressibility have been proposed over the 129

2 years.since the 1940 s engineers have realized the importance of developing empirical correlation for oil bubble point pressure and oil formation volume factor. Studies carried out in this field resulted in the development of new correlations. Several studies of this kind were published by Katz(1942[1, Standing (May, 1947[2, Lasater (May, 195[3. For several years, these correlations were the only source available for estimating bubble point pressureand oil formation volume factor when experimental data were unavailable. In the last thirty years there has been an increasing interest in developing new correlations for crude oils obtained from the various regions in the world. Glaso (May, 190[4,Vazquez andbeggs(190[5, Al-Marhoun(19[7,Abdul-Majeed and Salman (November, 19[,Kartoatmodjo and Schmidt (June, 1991[9,Dokla and Osman (March, 1992[10,Al-Marhoun (March, 1992[11,Macary and El-Batanoney (January, 1993[12,Omar and Todd (February, 1993[13,Petrosky and Farshad (October, 1993[14,De Ghetto et al ( October, 1994[15,Farshad et al (April, 1996[16,Hanafy et al ( February, 1997[17,Almehaideb ( March, 1997[1,Elsharkawy and Alikhan (May, 1997[19,Velarde et al ( June, 1997[20,Khairy et al (May, 199[21,Movagharnejad and Fasih (January, [22,Al-Shammasi ( February, [23,Dindoruk and Christman (September, 2001[24,Boukadi et al (January, 2004[25,Bolondarzadeh et al (2006[26,Mehran et al (2006[27,Hemmati and Kharrat ( March, 2007[2,Mazandarani and Asghari (September, 2007[29,Khamechi et al (March, 2009[30,Ikiensikimama and Ogboja (August,2009[31,Moradi et al (June, 2010[32,Okoduwa and Ikiensikimama (July, 2010[33,Elmabrouk((December 2010[34,Moradi et al (2013[35,Karimnezhad et al (2014[36andSulaimon et al (August,2014[37carried out some of the recent studies. A summary of bubble point pressureand oil formation volume factormodels are provided in Appendix B and Appendix Cincluding the formsof correlation used authors, and detailsof the data used for each development. III. Research Methodology To acheive this work,matlab statistical error analysis and MATLAB cross plot error analysis were usedto compare the performance and accuracy of oil bubble point pressure and oil formation volume factor models.the statistical parameters used for comparison are: average absolute percent relative error, standard deviationand the correlation coefficient IV. Data Acquisition and Analysis To achieve this study, the data sets used for this work were collected from different published literature papers and conventional PVT reports that derive the various fluid properties through differential liberation process from different oil fields in the Saudi Arabia and Yemen. Each data set contains bubble point pressure, formation volume factor, total solution gas oil ratio, average gas gravity, oil gravity, crude oil density, reservoir temperature and reservoir pressure. Statistical distributions such as maximum, minimum, mean, range, mid-range, variation and standard deviation of the input data are shown in Tables1. As can be seen from Table3.1, bubble-point pressure of the data ranged between psi a to 647 psia. For formation volume factor, the data ranged between 1.02 bbl/stb to 2.5 bbl/stb. Corresponding solution gas oil ratio ranged from scf/stb to 2637 scf/stb. Similar to solution gas oil ratio, oil gravity, crude oil density and average gas gravity varied between 15.3 to 63.7 API, to lb/ft3 and to 1.731, respectively. The reservoir temperature ranged between 5 0F to 294 0F. Corresponding reservoir pressure ranged from 165 psia to 2637 psia. data sets have been divided into the following three different API gravity classes: heavy oils for 0API 22, medium oils for 22 0API 31 and light oils for 0API

3 Table 1- Statistical descriptions of all data Property API P Min Max Mean Range Mid-Ran St. Dev V. Results and Discussion A large database consisting of data from oil PVT reports and literature sources has been compiled in order to evaluate bubble-point pressure and formation volume factormethods using statistical and graphical error analysis. 5.1Bubble Point Pressure CorrelationsAssessment Most bubble-point pressure correlations are a function of oil and gas gravity, solution gas-oil ratio and temperature. 2 methods for calculating bubble-point pressure have been evaluated using a large database consisting of data from oil PVT reports and literature sources. The best three correlations for each class and for the whole range of API gravity for bubble-point pressure have been summarized in Tables 2. As can be seen from Tables 2, Standing (1947 correlation outperforms the most common published empirical correlations followed by Vazquez and Beggs (190 and Velarde et al (997 correlationsfor whole data sets.standing (1947 correlation has an average absolute error of 19.3%, standard deviation of 44.5% and correlation coefficient of For heavy oils, the statistical analysis for all correlations indicate that Mehran et al (2006 correlation model is the best performing correlation model for heavy oils for 0API 22 with least average absolute error of 20.34%, least standard deviation of 41.69% and the highest correlation coefficient of 0.24 followed by Velarde et al (1997 and Al-Shammasi ( correlations. The statistical analysis for bubble point pressure correlations for medium oils for 22 0API 31 indicate Standing (1947 correlation outperforms the bubble point pressure published empirical correlations with least average absolute error of 25.4%, least standard deviation of % and the highest correlation coefficient of 0.47 followed by Al-Shammasi ( and Vazquez and Beggs(190 correlations. For light oils, the statistical analysis for all correlations illustrate that Vazquez and Beggs(190 correlation model is the best performing correlation model for light oils for 0API 31 with least average absolute error of 1.10%, least standard deviation of 31.19% and the highest correlation coefficient of 0.93 followed by Standing (1947 and Al- Kartoatmodjo and Schmidt (1991 correlations. The statistical accuracy of for all correlations for the data sets is summarized intablesa1(appendix A. The crossplots of estimated values against experimental values for the best three performing bubble-point pressure models (Standing, Vazquez and Beggs and Velarde et al are presented in Figures 1 through 3. The plotted points of the best three correlations fall very close to the perfect correlation of the 45 line. 131

4 Table 2Bubble point pressure correlations assessment summary Bubble point pressure correlations assessment summary for whole data sets Method Year No. of data AARE Std Standing Vazquez and Beggs Velarde et al Bubble point pressure correlations assessment summary for heavy oils( API 22 Mehran et al Velarde et al Al-Shammasi Bubble point pressure correlations assessment summary for medium oils( 22 0API 31 Standing Al-Shammasi Vazquez and Beggs Bubble point pressure correlations assessment summary for light oils( API 31 Vazquez and Beggs Standing Kartoatmodjo and Schmidt R Figure 1 Accuracy of Standing correlation Figure 2 Accuracy of Vazquez and Beggs-1 correlation 132

5 Figure 3 Accuracy of Velarde et al correlation 5.2 Oil Formation Volume Factor Correlations Assessment Statistical and graphical comparative were used to check the accuracy of oil formation volume factor correlations.the best three correlations for each class and for the whole range of API gravity for oil formation volume factor have been summarized in Tables 3. FromTables 3, the statistical analysis parameters for all correlations indicate that Al-Shammasi-2 ( correlation model is the best performing correlation model for the data used in this work followed by Kartoatmodjo and Schmidt (1991 and Farshad et al (1996 correlations.al-shammasi ( correlation has an average absolute error of 3.14%, standard deviation of 4.70% and correlation coefficient of The statistical analysis for all correlations indicate that Al-Shammasi-2 ( correlation model is the best performing correlation model for heavy oils with least average absolute error of 1.63%, least standard deviation of 2.55% and the highest correlation coefficient of followed by Farshad et al (1996 and Al-Marhoun-2 (1992 correlations. For medium oils, the statistical analysis for oil formation volume factor correlations indicate that Al-Shammasi-2 ( correlation model is the best performing correlation model for medium oils with least average absolute error of 1.7%, least standard deviation of 2.71% and the highest correlation coefficient of followed by Kartoatmodjo and Schmidt (1991 and Farshad et al (1996 correlations. The statistical analysis for oil formation volume factor correlations for light oils indicate AlShammasi-2 ( correlation outperforms the bubble point pressure published empirical correlations with least average absolute error of 3.59%, least standard deviation of 5.19 % and the highest correlation coefficient of followed by Kartoatmodjo and Schmidt(1991 and Mehran et al(2006 correlations. The statistical accuracy of for all formation volume factor for the data sets is summarized in TablesA2 (Appendix A. The crossplots of estimated values against experimental values for the best three performing formation volume factor models (Al-Shammasi, and Kartoatmodjo and Schmidt, Farshad et al are presented in Figures 4 through

6 Table 3 Oil formation volume factor correlations assessment summary Oil formation volume factor correlations assessment summary for whole data sets Method Year No. of data AARE Std R2 Al-Shammasi Kartoatmodjo and Schmidt Farshad et al Oil formation volume factor correlations assessment summary for heavy oils API 22 Al-Shammasi Farshad et al Al-Marhoun Oil formation volume factor correlations assessment summary for medium oils 22 0API 31 Al-Shammasi Kartoatmodjo and Schmidt Farshad et al Oil formation volume factor correlations assessment summary for light oils API 31 Al-Shammasi Kartoatmodjo and Schmidt Mehran et al Figure 4 Accuracy of Al-Shammasi-2 correlation Figure 5 Accuracy of Kartoatmodjo and Schmidt correlation 134

7 Figure 6 Accuracy of Farshad et al correlation VI. Conclusions Based on the analysis of the results obtained in this research study, the following conclusions can be made:1. Totally,63published black oil empirical correlations for oil bubble point pressure and oil formation volume factor were collected, summarized, evaluated. 2. A large database of crude oil properties was collected. 3. Standing (1947 correlation outperforms the most common publishedbubble point pressure empirical correlations followed by Vazquez and Beggs (190 and Velarde et al (997 correlations for whole data sets. 4. For heavy oils, the statistical analysis for all bubble point pressure correlations indicate that Mehran et al (2006 correlation model is the best performing correlation model with least average absolute error, least standard deviation and the highest correlation coefficient followed by Velarde et al (1997 and Al-Shammasi ( correlations. 5. The statistical analysis for bubble point pressure correlations for medium oils indicate that Standing (1947 correlation outperforms the bubble point pressure published empirical correlations followed by Al-Shammasi ( and Vazquez and Beggs(190 correlations For light oils, the statistical analysis for all bubble point pressure correlations illustrate that Vazquez and Beggs(190 correlation model is the best performing correlation model with least average absolute error of, least standard deviation and the highest correlation coefficient followed by Standing (1947 and Al- Kartoatmodjoand Schmidt (1991 correlations. 7. Foroil formation volume factor correlations,the statistical analysis parameters for all correlations indicate that Al-Shammasi ( correlation model is the best performing correlation model for for whole data sets used in this work followed by Kartoatmodjo and Schmidt (1991 and Farshad et al (1996 correlations.. The statistical analysis for all oil formation volume factor correlations indicate that Al-Shammasi ( correlation model is the best performing correlation model for heavy oils followed by Farshad et al (1996 and Al-Marhoun-2 (1992 correlations. 9. For medium oils, the statistical analysis for oil formation volume factor correlations indicate that Al-Shammasi ( correlation model is the best performing correlation model for medium oils with least average absolute error, least standard deviation and the highest correlation coefficient followed by Kartoatmodjo and Schmidt (1991 and Farshad et al (1996 correlations. 10. The statistical analysis for oil formation volume factor correlations for light oils indicate AlShammasi ( correlation outperforms the bubble point pressure published empirical 135

8 correlations 11. followed by Kartoatmodjo and Schmidt(1991 and Mehran et al(2006 correlations. References [1 Katz, D. L., Prediction of Shrinkage of Crude Oils, Drill & Prod. Pract., API,pp November,1942. [2 Standing, M.B., A Pressure Volume Temperature Correlation for Mixture of California Oils and Gases, Drill. & Prod. Prac., API, Dallas,pp , May,1947. [3 Lasater, J.S., Bubble Point Pressure Correlation, Trans., AIME,195. [4 Glaso, O., Generalized Pressure-Volume-Temperature Correlations, JPT,pp , May, 190. [5 Vasquez, M. and Beggs, H.D., Correlation for Fluid Physical Property Predictions, JPT,pp , June, 190. [6 Standing, M. B, Volumetric and Phase Behavior of Oil Field Hydrocarbon Systems, 9th ed. Dallas: Society of Petroleum Engineers,191. [7 Al-Marhoun, M.A., PVT Correlations for Middle East Crude Oils, JPT,pp , (May, 19. [ Abdul-Majeed, G. H. A. and Salman, N. H.: An Empirical Correlation for FVF Prediction, J Can. Pet. Tech.,pp , November, 19. [9 Kartoatmodjo, R.S.T. and Schmidt, Z., New Correlations for Crude Oil Physical Properties, paper SPE available from SPE Book Order Dept., Richardson, Texas [10 Dokla, M. and Osman, M., Correlation of PVT Properties for UAE Crudes, SPE Formation Evaluation,pp , March, [11 Al-Marhoun, M. A., New Correlation for formation Volume Factor of oil and gas Mixtures, Journal of Canadian Petroleum Technology,pp , March, [12 Macary, S.M. and El-Batanoney, M.H., Derivation of PVT Correlations for the Gulf of Suez Crude Oils, Journal of The Japan Petroleum Institute, Vol. 36,pp , (1993. [13 Omar, M.I. and Todd, A.C., Development of New Modified Black Oil Correlation for Malaysian Crudes, paper SPE 2533 presented at the SPE Asia Pacific Oil and Gas Conference, Singapore, February,1993. [14 Petrosky, G. and Farshad, F., Pressure-Volume-Temperature Correlation for the Gulf of Mexico, paper SPE presented at the SPE Annual Technical Conference and Exhibition, Houston, October,1993. [15 De Ghetto, G., Paone, F. and Villa, M., Reliability Analysis on PVT Correlations, paper SPE 2904presented at the European Petroleum Conference in London U.K., October, [16 Farshad, F. F, Leblance, J. L, Garber, J. D. and Osorio, J. G., Empirical PVT Correlations for Colombian Crude Oils, paper SPE presented at the SPE Latin American and Caribbean Petroleum Engineering Conference, Port of Spain, Trinidad and Tobago,April, [17 Hanafy, H. H., Macary, S. A., Elnady, Y. M., Bayomi, A. A. and El-Batanoney, M. H., Empirical PVT Correlations Applied to Egyptian Crude Oils Exemplify Significance of Using Regional Correlations, paper SPE presented at the SPE International Symposium on Oilfield Chemistry, Houston,February, [1 Almehaideb, R.A., Improved PVT Correlations for UAE Crude Oil, paper SPE presented at the Middle East Oil Conference and Exhibition, Manama, Bahrain,March, [19 Elsharkawy, A.M. and Alikhan, A.A., Correlations for Predicting Solution Gas/Oil Ratio, Oil Formation Volume Factor, and Undersaturated Oil Compressibility, J. Pet. Sci. Eng.,pp ,May, [20 Velarde, J. J., Blasingame, T. A., and McCain, W.D., Jr., Correlation of Black Oil Properties at Pressure Below Bubble Point Pressure A New Approach, Paper presented at the 4thATM of The Petroleum Society, Calgary,pp., 17, June,1997. [21 Khairy, M., El-Tayeb, S., and Hamdallah, M., PVT Correlations Developed for Egyptian Crudes, Oil and Gas J.,pp , May, 199. [22 Movagharnejad and Fasih., The New Correlation for Prediction Bubble Point pressure and Oil Formation Volume Factor for Iranian Reservoirs, Research Institute of Petroleum Industry,National Iranian Oil Company, January. [23 Al-Shammasi, A.A., Bubble Point Pressure and Oil Formation Volume Factor Correlations, paper SPE 5315 presented at the SPE Middle East Oil Show, Bahrain, February. [24 Dindoruk, B. and Christman, P.G., PVT Properties and Viscosity Correlations for Gulf of Mexico Oil, paper SPE presented at the SPE Annual Technical Conference and Exhibition, New Orleans, Louisiana, October2001. [25 Boukadi, F.H., Bemani, A.S and Hashemi, A., Pressure- Volume- Temperature Empirical Formulations for Understaturated Omani Oils, Petroleum Science and Technology, Online Publication Date: Petroleum Science and Technology,January, [26 Bolondarzadeh, A. and et al, The New PVT Generated correlations of Iranian Oil properties, 4th Iranian Petroleum Engineering Student conference,2006. [27 Mehran, F. Movagharnejad, K. and Didanloo, A., New Correlation for Estimation of Formation Volume Factor and Bubble Point Pressure for Iranian Oil Fields, First Iranian Petroleum Engineering conference, Tehran,

9 [2 Hemmati, M. N. and Kharrat, R., A correlation Approach for Prediction of Crude-Oil PVT Properties, paper SPE prepared for presentation at the 15th SPE Middle East Oil & Gas Show and Conference held in Bahrain International Exhibition Centre, Kingdom of Bahrain, March, [29 Mazandarani, M.T. and Asghari, S.M., Correlations for predicting solution gas-oil ratio, bubble point pressure and oil formation volume factor at bubble-point of Iran crude oils, European Congress of Chemical Engineering (ECCE6Copenhagen, September, [30 Khamehchi, R. and Ebrahimian, R., Novel empirical correlations for estimation of bubble point pressure, saturated viscosity and gas solubility of crude oils, Pet. Sci.,pp. 6-90,( March,2009,. [31 Ikiensikimama, S. and Ogboja, O., New bubble point pressure empirical pvt correlation, paper SPE 1293 presented at the SPE technical conference and exhibition in Abuja, Nigeria, August, [32 Moradi, B., Malekzadeh, E., Amani, M., Boukadi, F.H, and Kharrat, R., Bubble Point Pressure Empirical Correlation, paper SPE prepared for presentation at the Trinidad and Tobago Energy Resources Conference held in Port of Spain, Trinidad, June [33 Okoduwa, I.G. and Ikiensikimama, S.S. Bubble point Pressure Correlations for Niger Delta Crude Oils, paper SPE prepared for presentation at the 34th Annual SPE International Conference and Exhibition held in Tinapa, Calabar, Nigeria, August [34 Elmabrouk, S., Zekri,A. and Shirif, E., Prediction of Bubble-point Pressure and Bubble-point Oil Formation Volume Factor in the Absence of PVT Analysis, paper SPE prepared for presentation at the SPE Latin American & Caribbean Petroleum Engineering Conference held in Lima, Peru,December [35 Moradi, B., Malekzadeh, E., Mohammad, A S., Awang, M. and Moradie, P., New Oil Formation Volume Factor Empirical Correlation for Middle East Crude Oils, International Journal of Petroleum and Geoscience Engineering (IJPGE,pp ,( [36 Karimnezhad, M., Heidarian, M., Kamari, M. and Jalalifar, H., A new empirical correlation for estimating bubble point oil formation volume factor, Journal of Natural Gas Science and Engineering,pp , March,2014. [37 Sulaimon, A.A., Ramli, N., Adeyemi, B.J. and Saaid, I.M., New Correlation for Oil Formation Volume Factor, paper SPE prepared for presentation at the SPE Nigeria Annual International Conference and Exhibition held in Lagos, Nigeria, August Nomenclature = Bubble- point pressure, psia = Formation volume factor at the bubble- point pressure, RB/STB = Solution gas oil ratio, SCF/STB API = Oil density =crude oil density,lb/ft3 = Gas relative density (air=1.0 T= Reservoir temperature, degrees Fahrenheit P=Reservoir pressure,psia γ =gas gravity (air = 1 that would result from separator conditions of 100 psig γ =gas gravity obtained at separator conditions. P =actual separator pressure, psia T =actual separator temperature, 0F R = Separator solution gas oil ratio, SCF/STB. γ =Gas Specific gravity at separator pressure of psia. Min=minimum Max=maximum AARE = Average absolute percent relative error Std = Standard deviation error R2= Correlation coefficient 137

10 Appendix A Table A1 Statistical error analysis for bubble-point pressure correlations for whole data No Method Standing Lasater Glaso Vazquez and Beggs-1 Vazquez and Beggs-2 Al-Marhoun Kartoatmodjo and Schmidt-1 Kartoatmodjo and Schmidt-2 Dokla and Osman Macary and El-Batanoney Omar and Todd Petrosky and Farshad De Ghetto et al-1 De Ghetto et al-2 De Ghetto et al-3 Farshad et al Hanafy et al Almehaideb Velarde et al Khairy et al Movagharnejad and Fasih Al-Shammasi Dindoruk and Christman Boukadi et al Bolondarzadeh et al Mehran et al Hemmati and Kharrat Mazandarani and Asghari Khamechi et al Ikiensikimama and Ogboja Moradi et al Okoduwa and Ikiensikimama-1 Okoduwa and Ikiensikimama-2 Okoduwa and Ikiensikimama-3 Okoduwa and Ikiensikimama-4 Okoduwa and Ikiensikimama-5 Year No. of data AARE Std R

11 Table A2 Statistical error analysis for oil formation volume factor correlations for whole data No Method Year Standing Glaso Vazquez and Beggs Al-Marhoun-1 Abdul-Majeed and Salman Kartoatmodjo and Schmidt Dokla and Osman Al-Marhoun-2 Macary and El-Batanony Omar and Todd Petrosky and Farshad Farshad et al Hanafy et al Almehaideb Elsharkawy and Alikhan Al-Shammasi-1 Al-Shammasi-2 Dindoruk and Christman Mehran et al Hemmati and Kharrat Mazandarani and Asghari Elmabrouk Moradi et al Karimnezhad et al-1 Karimnezhad et al-2 Karimnezhad et al-3 Sulaimon et al No. of data AARE Std R Appendix B Bubble Point Pressure Empirical Correlationssummary Standing Correlation (May, 1947&1911,6 =1.2*[(.!" (10& 1.4 = / Lasater Correlation (May, ( = 5 =

12 9: = / / 5 =( ;( Glaso Correlation (May, 1904 log = log( / (log.a!a Vazquez and Beggs Correlation (June, 1905 API 30 D 10& = [C = ( A F"! / API 30 = [C56.1 = ( = D 10&.!FF? / [ IJ / Al-Marhoun Correlation (May, 197.@ J! = I" log ( I.!@@!F ". F"@."?J@ Kartoatmodjo and Schmidt Correlation (June, For API 30 =[ (.@A@ 10 ". F J&KL/(NOF?.@J!@ 10.!A&KL/(NOF?.AA!? For API 30 =[ ( = [ I.F?? Dokla and Osman Correlation (March, @F F@ = F. FA..A log ( AJJ!F Macary and El-Batanoney Correlation (January,

13 = P (.J P = exp [( ( / ( Omar and Todd Correlation (February, =1.2*[( T UVWXYZ( / 1.4 [ = (0.260 \ = ( : ( ( 1 + ( \ Petrosky and Farshad Correlation (October, = *[(( ^._``a ^.bacd 10& = IJ."A IF /.JF De Ghetto et al Correlation ( October, Heavy oils = *[(.@!!J ^.^^e^f ^.^gaehij Medium-oils: =[ k ll ( = k ll.! 10@. J"&KL/(NOF? [ I.F?? log ( Light oils =31.764*[( = @!J@, h m o = / Agip s sample = *[( = @?F?, h m o = / Farshad et al Correlation (April, = 10& = XYZ(p 0.26 (XYZp p=."@!. J" 10.?ANI.!&KL Hanafy et al Correlation ( February,

14 = Almehaideb Correlation ( March, = =.!A!?! Velarde et al Correlation ( June, = [(.! F?J I.? F!! 10T J."JF!A [ = !"@.2 10I? F Khairy et al Correlation (May, = J@@F I.F?@? I. " J.??F Movagharnejad and Fasih Correlation (January, 22 = IJ [ I [=.!F?A.?!! J? I.@?J"A? F.?" Al-Shammasi Correlation ( February, 23 = J.J@ J [exp ( [ ( @!"@? Dindoruk and Christman Empirical Correlation (September, = (. F!?JF I."@ J!"FA 10& = [ q [ = q = ( ( IF / I.@AFJAJ@.!F??A.J?F"? Boukadi et al Correlation (January, log( = o + \ + r s + t p u / v = log( , o = log (, \ = log ( r = log (( 32/1., s = 1.66 [log( t = 3.06 [log( p = 25.2 [log( XYZ ( XYZ ( XY Z0 1 XYZ (( 32/1. u = XY Z( log (, / = XY Z( XYZ (( 32/1. v = XY Z0 1 XYZ (( 32/1. Bolondarzadeh et al Correlation ( & z =27.16[wxy w{y

15 = \ = J@." F, o = A A, r = / Mehran et al Correlation ( ! "J = I." F.FF?A "."AJ."F?? Hemmati and Kharrat Correlation ( March, = *[( T UVWXYZ( /.617 [ = ( = ( : ( ( + ( Mazandarani and Asghari Correlation (September, JJ = IF I.@ AJ?.JF!? ( Khamechi et al Correlation (March, A A = I.??? /.! A?@. Ikiensikimama and Ogboja Correlation (August, ( = = ( } = ( / = ~= ~ ,9 = ( J! " F?J.J" A"J? A + ( } Moradi et al Correlation (June, = " 9 = log( / ( o = exp "! o ( (.?!!@J Okoduwa and Ikiensikimama Correlation (July, API 21 (Heavy Oil = A""F"@@ I.J"AF!?A I." J.?!@@@@. JA!F 21<API 26 (Medium Oil = A?J"?A?J?.!? "AJ.!F!" 143

16 26<API 35 (Blend Oil = J 35<API 45 (Light Oil = ( = ( } = ( / = ~= ~ ,9 = ( JFJ AF@.J@!"J + ( } API>45 (Very Light Oil = ?A"!@"A I.J?? A" A.FA " Appendix C Oil Formation Volume Factor Empirical Correlationssummary Standing Correlation (May, 1947&1911,6 = [ (.J Glaso Correlation (May, 1904 log( = 1 = log( (.JA (log Vazquez and Beggs Correlation ( June, 1905 API 30 β = IF R IJ (T 60 wapi γ t = I! R (T 60 wapi γ y+f y API 30 β = IF R IJ (T 60 wapi γ t = IA R (T 60 wapi γ γ =γ [ IJ API T y log ( P y+f 144

17 Al-Marhoun Correlation (May, 197 β = I" I t IJ t t=.@f"a.""af I. F Abdul-Majeed and Salman Correlation (November, 19 β = IF IJ t I t=. I. F@ IJ. t Kartoatmodjo and Schmidt Correlation (June, β = t.j t=.@jj =.J I.J [ I.F?? log ( Dokla and Osman Correlation (March, β = I I t IJ t t=.@@"j@.f F I.!!? J Al-Marhoun Correlation (March, β = I" t = I? I" (1 +t ( I" ( 60 Macary and El-Batanoney Correlation (January, β = [ ~ ~ = exp [ ( Omar and Todd Correlation ( February, = [ ~ = I" ( /.J Petrosky and Farshad Correlation ( October, β = IJ ~ ~=[."@"! (.A F.??J J"@ ". A"? Farshad et al Correlation (April, = & = XYZ( (XYZ9 145

18 9=.JAJ?."?A I."! Hanafy et al Correlation (February, = Almehaideb Correlation ( March, = I? Elsharkawy and Alikhan Empirical Correlation (May, = IJ IJ ( = IJ [ ( 60 Al-Shammasi Correlation ( February, 23 ( = I@ ( 60 ~ = ( ~ Dindoruk and Christman Correlation (September, = IF I? IJ ( 60 \ = [ ( IF.!JJ J ( 60.J!! ^. c^d^ ^.^^^` (NI?, = /.FFJ x z Mehran et al Correlation ( = & = XYZ( (XYZ9 9= [.F Hemmati and Kharrat Correlation ( March, = & = XYZ( (XYZ9 9= [.JAF? Mazandarani and Asghari Correlation (September, = I? ( 60 ~ ~ = I@ ( 60 (1 146

19 Elmabrouk Correlation ( = K Moradi et al Correlation ( = [ / ~=[ [.?F" F.?@? J K 0.02 : N ~. JF? Karimnezhad et al Correlation ( = I@ [ + ( ( = 1.66 = u = ( + 460I I. " + [ ( I. ". FF + [ ( I.J ( ( o = ( !AF ˆ.? Sulaimon et al Correlation (August, = ( = !AF 1+( I? ( ( ( I! ++o 147