CORRELATION EQUATIONS TO PREDICT REID VAPOR PRESSURE AND PROPERTIES OF GASEOUS EMISSIONS FOR EXPLORATION AND PRODUCTION FACILITIES
American Petroleum Institute
Executive Summary
1 Introduction
Overview of the Variables and Theoretical Context
Approach
2 Review of the Data
3 Analysis of Reid Vapor Pressure
Underlying Theory
Expected Empirical Relationships
Descriptive Statistics
Regression Analysis
4 Analyses of Gas Molecular Weights
Underlying Theory and Expected Predictors
Descriptive Statistics
Regression Analysis
5 Analyses of Mole Fractional Contributions of Hazardous
Air Pollutants to Hydrocarbon Emissions
Summary of Results
6 Analysis of Separator Gas Specific Gravity
Descriptive Statistics
Regression Analysis
7 Comparative Evaluation of Alternative Models and Inputs
Comparison of Flash Emission Estimates
Comparison of W & S Emission Estimates
Comparison of Total Emission Estimates
8 Conclusions
References
Appendix A - Quality-Reviewed Data Set for 94 Tanks
Figures
1.1 Illustration of crude oil extraction and storage
processes at an exploration and production storage tank
2.1 Frequency distributions of selected parameters for the
94-tank data set
2.2 Scatter plot matrix of selected parameters for the
94-tank data set
3.1 The relationship between RVP and bubble point observed
at 94 E & P storage tanks
3.2 Illustration of a single-parameter regression between
sales oil APIG and sales oil RVP (psia)
4.1 Relationships between the mole fraction of methane and
flash gas molecular weights
4.2 Performance of the recommended equation to predict
W & S gas molecular weight (MWTws)
4.3 Performance of the recommended equation to predict
flash gas molecular weight (MWTF)
4.4 Improved performance in the error of the estimate for
MWTWS
4.5 Improved performance in the error of the estimate for
MWTF
6.1 Performance of the recommended equation to predict
the logarithm of separator gas specific gravity, In
(SGSG)
6.2 Improved performance in the error of the estimate for
In(SGSG)
7.1 Comparison of the Vasquez-Beggs correlation equation
and E & P TANK results
7.2 Comparison of the Vasquez-Beggs correlation equation
and E & P TANK - 95 percent confidence bounds on the
agreement between estimated flash emissions
7.3 Comparison of AP-42 W & S emissions estimated from
default and correlated RVPs with AP-42 emissions
estimated from measured RVPs
7.4 Comparison of modeled (E & P TANK) and correlated
emissions with measured total THC emissions for seven
storage tanks
Tables
ES.1 Average speciation profiles, mole percent
2.1 Results of an initial examination of E & P TANK model
output for 103 E & P storage tanks
3.1 Descriptive statistics of variables used to predict
RVP
3.2 Single-parameter correlation coefficients for RVP
4.1 Descriptive statistics of variables used to predict
gas molecular weights
4,2 Single-parameter correlation coefficients for gas
molecular weights
5.1 Flash gas analysis: correlations to predict molar
contributions of HAPs to THC emissions
5.2 W & S gas analysis: correlations to predict molar
contributions of HAPs to THC emissions
5.3 Average speciation profiles modeled for the 94-tank
data set, mole percent
5.4 Comparison of average speciation profiles to the EPA
SPECIATE database, as weight percent
6.1 Descriptive statistics of variables used to predict
specific gravity of the separator gas
6.2 Single-parameter correlation coefficients for gas
molecular weights
8.1 Average speciation profiles, mole percent
Defines simple techniques for exploration and production (E&P) operators of petroleum storage tank facilities to meet environmental regulations. Recommended to estimate Reid Vapor Pressure, vented working and standing gas molecular weight, vented flash gas molecular weight, hydrocarbon speciation, (including hazardous air pollutants), and separator gas specific gravity.
| Document Type | Standard |
| Status | Current |
| Publisher | American Petroleum Institute |
