Fraction vaporized

Liquid mole fraction Vapor mole fraction Temper- ature, R Relative volatifity Pressure activity coefficient Endialpy, Btu/ (Ib-mol) Heat capacity, Btu/(lb-mol- R)... 

The corresponding acoustic velocity /(dp/dp, ), is normally much less than the acoustic velocity for gas flow. The mixture density is given in terms of the individual phase densities and the quality (mass flow fraction vapor) x by... 

G = Fractionator vapor rate, Ib/hr or packed column gas rate, Ibs/ft sec or pump flow, gpm GPM = Pump flow, gpm... 

If the material released is either in two phases or flashing, the quantity of material in the cloud (to be used in the calculation) is the lesser of (a) the product of twice the fraction vaporized and the total inventory of material or (b) the product of twice the fraction vaporized, the rate of release, and the time required to stop the leak. 

Assume exit fractional vaporization, x. Estimate range 15-40%. 

Rl Liquid volume fraction based on one-third of outlet fractional vaporization Figure 10-114 forSE = x /S ... 

Pressure drop ratio based on two-thirds the outlet fractional vapor Total tube length in which vaporization occurs Figure 10-114 forSE = 2xj./3 ... 

When a BLEVE occurs in a vessel, only a fraction of the liquid vaporizes the amount depends on the physical and thermodynamic conditions of the vessel contents. The fraction vaporized is estimated using the methods discussed in section 4-7. 

It is apparent that around 1925 distillation equipment in the petroleum industry varied in design and complexity from the simple horizontal shell stills with fractional vapor condensation to the continuous pipe stills with the progenitor of the present bubble cap fractionating columns. The basic processing principles were being rapidly extended, and the foundation was well established for the further development of distillation technology. 

Component Composition, mole fraction Vapor pressure at 150°F, ... 

Procedure for finding the heat trensfer coefficient and required temperature difference when the heat flux q, mass rate of flow m and fraction vapor x are specified... 

Forced circulation reboilers may be either horizontal or vertical. Since the feed liquid is at its bubblepoint, adequate NPSH must be assured for the pump if it is a centrifugal type. Linear velocities in the tubes of 15-20 ft/sec usually are adequate. The main disadvantages are the costs of pump and power, and possibly severe maintenance. This mode of operation is a last resort with viscous or fouling materials, or when the fraction vaporized must be kept low. 

On combining these equations and introducing j8 = V/F, the fraction vaporized, the flash condition becomes... 

For fixed value of the vaporization constant, regardless of droplet size, a graph presented by Probert (98) shows fraction vaporized as a function of n, x, X, and t. When X is not constant with change of droplet size, this graph does not apply. Nevertheless, its significance in development of vaporization analysis techniques has been great. 

Kol Overall mass transfer coefficient, kmol/ lb.mol/ y" Mole fraction, vapor phase, ... 

In Equations (7.6), Mc, xijD, Vi,d, and Tc are the molar liquid holdup, the liquid mole fraction and vapor mole fraction of component 1, and the temperature in the condenser, xgj, ygj, and T are the molar liquid holdup, the liquid mole fractions and vapor mole fractions of component 1, and the temperature on stage i, and Mb, xgB, Vi,b, and TB are the corresponding holdup, liquid mole fractions, vapor mole fractions, and temperature in the reboiler. Oi are the stage enthalpies and A j is the latent heat of vaporization of component j, j = 1,2. By expressing the stage enthalpies as a function of the stage temperatures, Oi = MiCPt Ti, Equations (7.6) can be rewritten as... 

Sequential Modular. By far the most experience with flowsheeting systems has been with the sequential modular architecture (59- 3). It is this architecture that is most easily understood by the process engineer. Each module calculates all output streams from input streams subject to module parameters. Generally, the stream variables consist of component flows, temperature (or enthalpy) and pressure as the independent variables. Other dependent variables such as total flow, fraction vapor and total enthalpy (or temperature) are often carried in the stream. 

This is the quality (fraction vapor) of the discharge stream at point 2. The enthal H 2 is also given by Eq. (6.53), written... 

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