Difference between revisions of "McCain Oil Formation Volume Factor equation"

From wiki.pengtools.com
Jump to: navigation, search
(Math & Physics)
Line 9: Line 9:
 
== Math & Physics ==
 
== Math & Physics ==
  
Pseudoliquid density:
+
:<math>B_o} = \frac{\rho_{STO}+1.22117R_s\gamma_g}{\rho_{oR}}</math>
 
 
:<math>\rho_{po} = 52.8 - 0.01 R_{sb}</math>
 
 
 
Apparent liquid density:
 
 
 
:<math>\rho_a = a_0 + a_1\ SG_{gSP} + a_2\ SG_{gSP}\ \rho_{po} + a_3\ SG_{gSP}\ \rho_{po}^2 + a_4\ \rho_{po} +a_5\ \rho_{po}^2 </math>
 
:<math>a_0 = -49.8930</math>
 
:<math>a_1 = 85.0149</math>
 
:<math>a_2 = - 3.70373</math>
 
:<math>a_3 = 0.0479818</math>
 
:<math>a_4 = 2.98914</math>
 
:<math>a_5 =- 0.0356888</math>
 
 
 
Next pseudoliquid density<ref name= M1990/>:
 
:<math>\rho_{po} = \frac{R_s\ SG_g + 4,600\ SG_o}{73.71+R_s\ SG_g\ / \rho_a}</math>
 
 
 
Iterate until pseudoliquid densities are equal.
 
 
 
Next adjust density to the pressure of interest:
 
 
 
:<math>\rho_{bs} = \rho_{po} + \triangle \rho_P </math>
 
 
 
where
 
 
 
:<math>\triangle \rho_{P} = \left ( 0.617 + 16.181 \times 10^{-0.0425\ \rho_{po}} \right) \frac{P}{1000} - 0.01 \left ( 0.299 + 263 \times 10^{-0.0603\ \rho_{po}}\right)\ \left (\frac{P}{1000}\right)^2 </math>
 
 
 
Adjust density to the temperature of interest:
 
 
 
:<math>\rho_{o} = \rho_{bs} + \triangle \rho_T </math>
 
 
 
where
 
 
 
:<math>\triangle \rho_T = (0.00302 + 1.505\ \rho_{bs}^{-0.951}) (T - 60)^{0.938} - (0.0216 - 0.0233\ (10^{-0.0161\ \rho_{bs}})) (T - 60)^{0.475}</math>
 
 
 
Oil density above the bubble point pressure:
 
 
 
:<math>\rho_{o} = \rho_{b}\ e^{c_o\ (P - P_b)} </math>
 
  
 
== Example. Calculation of the oil density ==
 
== Example. Calculation of the oil density ==

Revision as of 10:28, 28 September 2020

McCain Oil Formation Volume Factor correlation

McCain correlation is an empirical correlation for the oil formation volume factor published in 1990 [1].

McCain Oil Formation Volume Factor correlation in the PVT Software

Math & Physics

Failed to parse (syntax error): B_o} = \frac{\rho_{STO}+1.22117R_s\gamma_g}{\rho_{oR}}

Example. Calculation of the oil density

Example source [2]

Input data

R_s = 53.24 sm3/sm3
SG_o = 0.85 or 35 API
SG_g = 0.75
T = 90C or 363K
P = 10 MPa

Calculate oil density at p = 10 MPa?

Solution

\rho_o = 749.645 kg/m3

The solution is available in the online PVT calculator software model at www.pengtools.com

Application range

Description of the Data Used[3]:

  133 \le P_b \le 6,700
  77 \le T \le 327
  18 \le R_{sb} \le 1,975
  0.76 \le SG_o \le 0.95
  0.556 \le SG_g \le 1.237
  31.3 \le \rho_{ob} \le 55.77

Number of data sets = 684

Nomenclature

 c_o = oil compressibility, 1/psia
 P = pressure, psia
 R_s = solution gas-oil ratio, scf/stb
 SG_g = gas specific gravity, dimensionless
 SG_{gSP} = gas specific gravity at separator pressure, dimensionless
 SG_o = oil specific gravity, dimensionless
 T = temperature, °F
 \rho_{a} = apparent density of surface gas if it were a liquid, lbm/ft3
 \rho_{ob} = liquid density at the bubble point pressure, lbm/ft3
 \rho_{bs} = liquid density at reservoir pressure and 60°F, lbm/ft3
 \rho_o = oil density, lbm/ft3
 \rho_{po} = pseudoliquid formed by recombination of surface gas and liquid at standard conditions, lbm/ft3
 \triangle \rho_{P} = adjustment to liquid density due to pressure, lbm/ft3
 \triangle \rho_{T} = adjustment to liquid density due to temperature, lbm/ft3

Subscripts

b - bubble point
g - gas
o - oil

References

  1. McCain, W.D. Jr. (1990). Properties of Petroleum Fluids (2 ed.). Oklahoma: PennWell Corp. ISBN 978-0878143351. 
  2. Wolcott, Don (2009). Applied Waterflood Field DevelopmentPaid subscription required. Houston: Energy Tribune Publishing Inc. 
  3. McCain, W.D. Jr.; Hill, N. C. (1995). "Correlations for Liquid Densities and Evolved Gas Specific Gravities for Black Oils During Pressure Depletion"Free registration required. Society of Petroleum Engineers (SPE-30773-MS).