Reid vapor pressures

The Reid vapor pressure characterizes the light petroleum products it is measured by a standard test (refer to Chapter 7) which can be easily simulated. 

The two chambers are opened to each other and the apparatus is brought to 37.8°C. The relative pressure resulting is called the Reid vapor pressure . 

The Reid vapor pressure is generally barely different from the true vapor pressure at 37.8°C if the light gas content —methane, ethane, propane, and butane— of the sample is small, which is usually the case with petroleum products. The differences are greater for those products containing large quantities of dissolved gases such as the crude oils shown in Table 4.13. 

Reid vapor pressure, bar Vapor pressure crude oil, bar Vapor pressure gasoline, bar R crude oil R stabilized gasoline... 

Relation between the true vapor pressure at 37.8 C and the Reid vapor pressure. R = True vapor pressure/ Reid" vapor pressure. --------------------------------------------------------------------------------i... 

The criterion retained up to now in the specifications is not the true vapor pressure, but an associated value called the Reid vapor pressure, RVP. The procedure is to measure the relative pressure developed by the vapors from a sample of motor fuel put in a metallic cylinder at a temperature of 37.8°C. The variations characteristic of the standard method are around 15 millibar in repeatability and 25 millibar in reproducibility. 

Reid vapor pressures and flash points of selected crude oils. 

Debutanized gasoline cuts from Arabian Light crude. Reid Vapor Pressure as a function of yield, weight %. Aromatics content as a function of yield, volume %. 

Reid vapor pressure NF EN 12 (M 07-007) ISO 3007 ASTM D 323 Pressure in a sample bomb held at 37.8°C... 

Fuel vapor pressure, or Reid vapor pressure (RVP) is predominantiy influenced by the amount of C-4 in the fuel. California, other of the United States, and the EPA have or are restricting fuel RVP for both seasonal and areas (latitude). These restrictions greatiy reduce all gasoline evaporative losses. 

Normally, the crude or condensate sales contract will specify a maximum Reid Vapor Pressure (RVP). This pressure is measured according to... 

Figure 6-6. Relationship betv/een Reid vapor pressure and actual vapor pressure. (From Gas Processors Suppliers Association, Engineering Data Book, 9th Edition.)...

Flammable Liquid A term used to classify certain liquids as defined by NFPA 30 as a liquid with a closed-cup flash point below 100°F (37.8°C) and Reid vapor pressures not exceeding 40 psia at 100°F (37.8°C). Flammable liquids are called Class I liquids and have three subdivisions as follows ... 

As the gasoline Reid vapor pressure (RVP) is reduced, the operation ol the debutanizer becomes more critical. The allowable vapor pressure in gasoline makes it difficult to prevent heavy ends in the alkylation feed. This can limit the production of gasoline without sacrificing alkylation. This limitation is often from insufficient overhead cooling and reboiling ... 

Reid Vapor Pressure (RVP) is gasoline vapor pressure at I00°F. 

A tank containing 1500 m3 of naphtha is to be blended with two other hydrocarbon streams to meet the specifications for gasoline. The final product must have a minimum research octane number (RON) of 95, a maximum Reid Vapor Pressure (RVP) of 0.6 bar, a maximum benzene content of 2% vol and maximum total aromatics of 25% vol. The properties and costs of the three streams are given in the Table 3.5. 

This is the property of a substance to vaporize. Liquids are usually classified by the Reid vapor pressure, which is calculated on the basis of a specific oil at a temperature of 37.8 °C (100 °F). 

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