There’s a small question regarding the partial pressures of oil and gas
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When the water content in the crude oil fed to the initial distillation tower increases, although the pressure at the top of the tower rises, the presence of large amounts of water vapor reduces the vapor pressure of the oil and gas, thereby increasing the dry point of the gasoline at the tower top. Why does a lower vapor pressure of oil and gas result in a higher dry point? What is the effect of a low vapor pressure of oil and gas on distillation, and what is the effect of a high vapor pressure?
Please take a look at the principle of stripping. Additionally, it is best that the material fed into the tower does not contain water, to avoid a sudden increase in vaporization volume that could cause the trays to flip over
Relationship between pressure and boiling point – Lower pressure results in a lower boiling point.
A low partial pressure of oil and gas facilitates gasification; this is the principle behind steam stripping
Why does a lower vapor pressure of oil and gas result in a higher dry point? What is the effect of a low vapor pressure of oil and gas on distillation, and what is the effect of a high vapor pressure? With a low vapor pressure of the oil, it is easier for the oil to vaporize; at the same temperature, the amount distilled increases. Similarly, the dry point of the distilled oil increases. It is more conducive to the distillation of light components. If the oil vapor pressure is high, the oil is less likely to vaporize, and the components in the overhead distillate become lighter.
When the pressure at the top of the tower is high, the corresponding vapor pressure of oil and gas is lower; as a result, more product is distilled out, and heavier components are carried away, which leads to a higher dry point of the gasoline
I think we can use the pressure division law: the partial pressure of component A = the saturated vapor pressure of A * the molar fraction of component A in the liquid phase. When the partial pressure of component A decreases, while its saturated vapor pressure remains constant, the mole fraction of component A in the liquid phase drops. This indicates an increase in the amount of gas-phase components, as well as an increase in the concentration of the heavier components, resulting in a rise in the dry point.