Difference between revisions of "McCain Oil density correlation"

From wiki.pengtools.com
Jump to: navigation, search
(→‎Application range)
Line 47: Line 47:
 
Description of the Data Used<ref name= M1995/>:
 
Description of the Data Used<ref name= M1995/>:
  
−
:<math>  20 \le R_s \le 2,070 </math>
+
:<math>  133 \le P_b \le 6,700 </math>
−
:<math>  0.75 \le SG_o \le 0.96 </math>
+
:<math>  77 \le T \le 327 </math>
−
:<math>  0 \le P \le 5250 </math>
+
:<math>  18 \le R_{sb} \le 1,975 </math>
−
:<math>  70 \le T \le 295 </math>
+
:<math>  0.76 \le SG_o \le 0.95 </math>
 +
:<math>  0.556 \le SG_g \le 1.237 </math>
 +
:<math>  31.3 \le \rho_{ob} \le 55.77 </math>
  
−
Number of oil systems = 600<BR/>
+
Number of data sets = 684<BR/>
−
Number of dead oil observations = 460<BR/>
 
−
Number of live oil observations = 2,073<BR/>
 
  
 
=== Nomenclature ===
 
=== Nomenclature ===

Revision as of 13:37, 26 July 2017

Brief

McCain is an empirical correlation for the oil density published in 1995 [1].

Oil density in the PVT Tool

Math & Physics

Pseudoliquid density:

\rho_{po} = 52.8 - 0.01 R_{sb}

Apparent liquid density:

\rho_a = -49.8930 + 85.0149\ SG_g - 3.70373\ SG_g\ \rho_{po} + 0.0479818\ SG_g\ \rho_{po}^2 + 2.98914\ \rho_{po} - 0.0356888\ \rho_{po}^2

Next pseudoliquid density:

\rho_{po} = \frac{R_s\ SG_g + 4,600\ SG_o}{73.71+R_s\ SG_g\ / \rho_a}[2]

Iterate until pseudoliquid densities are equal.

Adjust density to the pressure of interest:

\rho_{bs} = \rho_{po} + \triangle \rho_p

where

\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


Adjust density to the temperature of interest:

\rho_{o} = \rho_{bs} + \triangle \rho_t

where

\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}

Adjust density above the bubble point pressure:

\rho_{o} = \rho_{b}\ e^{c_o\ (P - P_b)}

Discussion

Application range

Description of the Data Used[1]:

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

A = coefficient
B = coefficient
m = coefficient
P = pressure, psia
R_s = solution gas-oil ratio, scf/stb
SG_o = oil specific gravity, dimensionless
T = temperature, °F
x = coefficient
\mu = viscosity, cP

Subscripts

b - bubble point
od - dead oil
os - saturated oil
o - undersaturated oil

References

  1. ↑ 1.0 1.1 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). 
  2. ↑ McCain, W.D. Jr. (1990). Properties of Petroleum Fluids (2 ed.). Oklahoma: PennWell Corp. ISBN 978-0878143351. 
Retrieved from "https://wiki.pengtools.com/index.php?title=McCain_Oil_density_correlation&oldid=2696"