Under the ASTM Method D 323 (Reid vapour pressure), it is the absolute vapour pressure exerted by a liquid at 100°F. The higher this value, the more volatile the sample and the more readily it will evaporate. Unlike distillation data, vapour pressure provides a single value that reflects the combined effect of the individual vapour pressure of the different petroleum fractions in accordance with their mole ratios. It is thus possible for two wholly different products to exhibit the same vapour pressure at the same temperature - provided the cumulative pressures exerted by the fractions are the same. A narrow-cut distillate, for example, may exhibit the same vapour pressure as that of a dumbbell blend, where the effect of heavy fractions is counterbalanced by that of the lighter ones. In conjunction with other volatility data. Reid vapour pressure plays a role in the prediction of gasoline performance.
The typical Reid vapor pressure range in naphtha is between 2 to 15 pounds per square inch (psi). Reid vapor pressure is a measure of the vapor pressure of volatile petroleum products, including naphtha. High Reid vapor pressure indicates increased volatility.
Chilling the sample in the Reid vapor pressure test helps to reduce the vapor pressure of the volatile components in the sample, making it easier to measure accurately. This allows for more precise determination of the vapor pressure under controlled conditions.
Vapor pressure is the pressure exerted by a vapor in equilibrium with its condensed phase (liquid or solid) at a given temperature. Vapor density, on the other hand, is the mass of a vapor per unit volume of air. In essence, vapor pressure relates to the equilibrium between the vapor and its condensed phase, while vapor density pertains to the mass of vapor in a given volume of air.
When you add a teaspoon of honey to water with vapor pressure, it will reduce the vapor pressure. The sugar in the honey leads to the pressure going down.
When the vapor pressure equals atmospheric pressure at the surface of a liquid, it has reached its boiling point. This is the temperature at which the vapor pressure of the liquid is equal to the pressure exerted on it by the surrounding atmosphere, causing the liquid to change into vapor.
Reid vapor pressure (RVP) of gasoline is the vapor pressure at 100°F.
The typical Reid vapor pressure range in naphtha is between 2 to 15 pounds per square inch (psi). Reid vapor pressure is a measure of the vapor pressure of volatile petroleum products, including naphtha. High Reid vapor pressure indicates increased volatility.
The Reid vapor pressure of LPG (liquefied petroleum gas) typically ranges from 100 to 200 psi (pounds per square inch) at 100°F. Reid vapor pressure is a measure of the volatility of a fuel, indicating its tendency to evaporate.
Chilling the sample in the Reid vapor pressure test helps to reduce the vapor pressure of the volatile components in the sample, making it easier to measure accurately. This allows for more precise determination of the vapor pressure under controlled conditions.
The volatility of gasoline.
The amount of light components in the oil affect the reid vapor vapor pressure. In petroleum products such as gasoline, the amount of butane in the gasoline blend has a strong affect on the Reid Vapor Pressure. To reduce RVP more stripping steam can be added to the product strippers. The fractionation in the debutanizer might also need to be adjusted to affect the RVP.
its just under 0.5 pounds.
http://www.epa.gov/ttn/chief/ap42/ch07/final/c07s01.pdf page 56
The vapor pressure deficit formula is used to calculate the difference between the actual vapor pressure and the saturation vapor pressure in the atmosphere. It is calculated by subtracting the actual vapor pressure from the saturation vapor pressure.
Depends on temperature. For ASTM D323 the RVP of water is ~49.5 mmHg (torr) gauge or ~809 mmHg absolute (assuming standard pressure). FYI - ASTM D323 is measured at 100F.
The vapor pressure graph shows that as temperature increases, the vapor pressure also increases. This indicates a direct relationship between temperature and vapor pressure, where higher temperatures result in higher vapor pressures.
To calculate the vapor pressure deficit (VPD), subtract the actual vapor pressure (e) from the saturation vapor pressure (es) at a given temperature. The actual vapor pressure can be calculated using the relative humidity (RH) and the saturation vapor pressure can be determined from the temperature. The formula is VPD es - e, where es saturation vapor pressure and e actual vapor pressure.