Benzene emissions occur during marine vessel loading operations. These emissions are regulated in several countries. Accordingly, we developed a one-dimensional benzene diffusion model advancing in the vertical direction within cargo tanks. Unlike other models, the model presented in this paper is based on a 1/10 scale modeling of eddy diffusion at the liquid surface during initial loading operations and advection under the tank roof during final loading operations. The model input parameters include loading rate, flow rate, cargo tank size, and temperature dependent saturated concentrations. The validity of the model is demonstrated by comparisons with onboard measurements. Other models exist. However, they are based on empirical estimates rather than rational modeling.

Issue Section:
Technical Papers
Keywords:
organic compounds, loading, freight handling, air pollution, surface diffusion
Topics:
Benzene, Diffusion (Physics), Eddies (Fluid dynamics), Viscosity, Tankers, Emissions
1.
U.S. EPA, 1998, “Carcinogenic Effects of Benzene: An Update,” EPA/600/P-97/001F.
2.
American Petroleum Institute, 1959, “Evaporation Loss from Tank Cars, Tank Trucks and Marine Vessels,” API Bull. 2514.
3.
American Petroleum Institute, 1981, “Atmospheric Hydrocarbon Emissions from Marine Vessels Transfer Operations,” 2nd Edition API Publication 2514A.
4.
American Petroleum Institute, 1992, “Impact Assessment of New Data on the Validity of American Petroleum Institute Marine Transfer Operation Emission Factors,” API Publication 2524.
5.
Yoshizawa, A., Murakami, S., Kobayashi, T., Taniguchi, N., et al., 1995 “Analysis of Turbulent Flows,” University of Tokyo Press, pp. 26 in Japanese
6.
Crank, J., 1955, “The Mathematics of Diffusion,” Oxford at the Clarendon Press, pp. 147-148.
7.
Reid, R. C., Prausnitz, J. M., and Poling, B. E., 1987, The Properties of Gases & Liquids, fourth edition, McGraw-Hill, pp. 208.
8.
Cussler, E. L., 1997, “Diffusion, Mass Transfer in Fluid Systems,” second edition, Cambridge University Press, Cambridge UK, pp. 63, 104
9.
Bird, R. B., Stewart, W. E., and Lightfoot, E. N., 1960, “Transport Phenomena,” John Wiley & Sons, New York City, pp. 510.
10.
Majima, T., Yamaguchi, K., Yamanouchi, H., Fujii, S., and Sakamoto, S., 2000, “Experiment Using Scale Model of Cargo Tank to Estimate the Concentration of Benzene Gas Emitted from Chemical Tanker During Loading Operation,” proceedings, 5th International Conference on Health, Safety and Environment, SPE paper 61504.
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 by ASME
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