Page 155 - Environmental Control in Petroleum Engineering

142 Environmental Control in Petroleum Engineering

4.3 ATMOSPHERIC PATHS

Many petroleum industry wastes are gaseous and will be dispersed
into the air, where they are transported with the wind. Upon release,
airborn pollutants undergo transport by wind (advection), dispersion
from atmospheric turbulence, and removal from deposition on the ground,
vegetation, and buildings. Chemical transformations may also take place
that alter the chemical and/or physical state of the emitted pollutant.
Onshore sources of air pollutants are generally regulated by the total
emission rates, while offshore sources are generally regulated so that
the resulting onshore levels of pollutants are below specified levels.
To obtain permits to emit air pollutants for many applications, air-
quality modeling is required (Sheehan, 1991). Such modeling relates
the downwind concentration of released pollutants to their emission
rates. Computer-based models are available that use information on
the emission rate, physical characteristics of the emission source, the
topography of the terrain over which the pollutants travel, and the mete-
orological conditions of the area to calculate the pollutant concentration
downwind of the source (Moroz, 1987; Smith, 1987; American Petrol-
eum Institute, 1983a; American Petroleum Institute, 1984; American
Petroleum Institute, 1985a; American Petroleum Institute, 1985b). A
discussion of models accepted by the U.S. Environmental Protection
Agency is available (U.S. Environmental Protection Agency, 1986),

REFERENCES

American Petroleum Institute, "Model Performance Evaluation for Offshore
Releases," API Publication 4387, Washington, D.C., Dec. 1983a.
American Petroleum Institute, "Summary and Analysis of API Onshore
Drilling Mud and Produced Water Environmental Studies," API Bulletin
D19, Washington, D.C., Nov. 1983b.
American Petroleum Institute, "Dispersion of Emissions from Offshore Oil
Platforms—A Wind-Tunnel Modeling Evaluation," API Publication 4402,
Washington, D.C., May 1984.
American Petroleum Institute, "Plume Rise Assessment Downwind of Oil
Platforms for Neutral Stratification," API Publication 4420, Washington,
D.C., Dec. 1985a.
American Petroleum Institute, "Development and Application of a Simple
Method for Evaluating Air Quality Models," API Publication 4409,
Washington, D.C., Jan. 1985b.