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Two kinds of membranes modules, vapor retained glassy membrane based on PEEK hollow fiber membrane modules and vapor permeated rubbery membrane system based on GMT plate-and-frame membrane modules, were used to control the oil vapor pollution during the course of receiving and transferring gasoline in oil station. The efficiencies of the membrane module and the membrane system of them were evaluated and compared respectively in the facilities which were developed by ourselves. It was found that both the two kinds of membranes modules had high efficiency for the separation of VOCs-air mixed gases, and the outlet vapor after treatment all can meet the national standard. When the vapor-enriched gas was returned to the oil tank to simulate the continuously cycle test, the concentration of VOCs in the outlet was also below 25 g x m(-3).

With the gradual improvement of environmental regulations, more and more attentions are attracted to the vapor emissions during the process of vehicle refueling. Research onto the vehicle refueling process by means of numerical simulation has been executed abroad since 1990s, while as it has never been involved so far domestically. Through reasonable simplification about the physical system of "Nozzle + filler pipe + gasoline storage tank + vent pipe" for vehicle refueling, and by means of volume of fluid (VOF) model for gas-liquid two-phase flow and Re-Normalization Group kappa-epsilon turbulence flow model provided in commercial computational fluid dynamics (CFD) software Fluent, this paper determined the proper mesh discretization scheme and applied the proper boundary conditions based on the Gambit software, then established the reasonable numerical simulation model for the gas-liquid two-phase flow during the refueling process. Through discussing the influence of refueling velocity on the static pressure of vent space in gasoline tank, the back-flowing phenomenon has been revealed in this paper. It has been demonstrated that, the more the flow rate and the refueling velocity of refueling nozzle is, the higher the gross static pressure in the vent space of gasoline tank. In the meanwhile, the variation of static pressure in the vent space of gasoline tank can be categorized into three obvious stages. When the refueling flow rate becomes higher, the back-flowing phenomenon of liquid gasoline can sometimes be induced in the head section of filler pipe, thus making the gasoline nozzle pre-shut-off. Totally speaking, the theoretical work accomplished in this paper laid some solid foundation for self-researching and self-developing the technology and apparatus for the vehicle refueling and refueling emissions control domestically.