Liquid propane-saturated

Example 20 Estimate the Density of Saturated Liquid Propane... 

The speciflc work done by the fluid in expansion can be read from Figures 6.30 or 6.31 if its temperature is unknown. Saturated propane at a pressure of 1.9 MPa (19 bar) has a temperature of 328 K, almost the superheat-limit temperature. Note that it is assumed that temperature is uniform, which is not necessarily the case. From Figure 6.30, the expansion work per unit mass for saturated liquid propane is... 

The mass of released liquid propane is 11,958 kg, as was calculated in Section 9.1.6. This gives, for the energy of the explosion for the saturated liquid ... 

The specific work done by a fluid in expansion is read from Figure 6.31 saturated liquid butane 21 MJ/m saturated butane vapor 2.5 MJ/m saturated liquid propane 30 MJ/m saturated propane vapor 8 MJ/m ... 

The reason is condensate backup. The condensate backup causes subcooling that is, the liquid is cooled below its bubble point, or saturated liquid temperature. Perhaps a rat has lodged in the condensate outlet pipe. The rat restricts condensate drainage from the shell side. To force its way past the dead rat, the propane backs up in the condenser. The cold tubes in the bottom of the shell are submerged in liquid propane. The liquid propane is cooled below its bubble-point temperature. 

Residua and heavy oils, like any other petroleum, can be fractionated by a variety of techniques (Speight, 1999) to provide broad general fractions termed asphaltenes, resins, aromatics, and saturates (Figure 6-6). By convention, the asphaltene and resin fractions are often referred to as the asphaltic fraction because of their insolubility in liquid propane and subsequent separation from a liquid propane solution of residua as asphalt. 

Saturated propane vapor at 2.00 x 10 psia is fed to a well-insulated heat exchanger at a rate of 3.00 X 10 SCFH (standard cubic feet per hour). The propane leaves the exchanger as a saturated liquid (i.e., a liquid at its boiling point) at the same pressure. Cooling water enters the exchanger at 70°F. flowing cocurrently in the same direction) with the propane. The temperature difference between the outlet streams (liquid propane and water) is 15°F. 

Incidentally, its viscosity and surface tension decrease to nearly negligible values as the critical temperature is approached. Over this range propane changes from a typical liquid to a fluid possessing substantially the properties of gas. As the 220°F [100°C] isotherm indicates, gaseous propane at a pressure of 1000 pounds per square inch [69 bar] is much more dense than liquid propane at 212°F [100°C] and its saturation pressure. Also, as the liquid approaches its critical temperature, it becomes highly compressible. 

Example 20 Estimate the density of saturated liquid propane at 0°C. Use Eq. (2-84). 

Problem 6.5 Liquid propane boils in a constant pressure boiler to produce propane vapor at 30 bar and 245 °C. At the inlet of the boiler the propane is saturated liquid. 

Problem 7.20 Use the program you wrote in Problem 7.IQ to construct a PH graph for propane using as reference state the saturated liquid at 350 K. You may do this as follows First, obtain the residual enthalpy of the saturated liquid at 350 K. Next, calculate P= , and the residual enthalpy and entropy of the saturated liquid and saturated vapor at various temperatures between To and 250 K. Using these residuals and the specified reference state, calculate the absolute enthalpy of the saturated phases. 

Substances considered in a compilation of the thermodynamic properties of refrigerants include hydrogen, parahydrogen, helium, neon, nitrogen, air, oxygen, argon, carbon dioxide, hydrocarbons (e.g. methane, ethane, propane, butane, isobutane, ethylene, and propene), and fluoro-and fluoro-chloro-hydrocarbons. Properties listed include those for the liquid and saturated vapour, superheated vapour, and unsaturated vapour. In addition, pressure-enthalpy, and in some instances pressure-entropy, diagrams are provided. 

Example G.2 A rigid container is filled completely with saturated liquid propane at 100 psia. We now transfer heat to it, allowing time for perfect thermal mixing, and ask how fast does the pressure rise as we introduce heat. From the first law we know that for a closed system at constant volume dU = mdu = dQ, so we are asking for dP/du)y. This is one of the 168 derivatives derivable from Table G. 1 but not one of the 10 most often used. This example is a very simplified version of the problem addressed in [1]. 

One mole of saturated liquid propane and 1 mole of saturated vapor are contained in a rigid container at 0°C and 4.68 bar. How much heat must be supplied to evaporate all of the propane. At 0°C,... 

Examfile Saturated iqJd/ vapour prepare systein enters PPiV and the liquid propane... 

Fig. 8. Partial molar volumes in the saturated liquid phase of the propane-methane system at IOO°F. (O) (0) Data of B. H. Sage and W. N. Lacey, Some Properties of the Lighter Hydrocarbons, Hydrogen Sulfide, and Carbon Dioxide. American Petroleum...

A saturated liquid mixture of ethane, propane, n-butane, n-pentane and n-hexane given in Table 9.9 is to be separated by distillation such that 95% of the propane is recovered in the distillate and 90% of the butane is recovered in the bottoms. Estimate the distribution of the other components for a column operating at 10 bar. Assume that the K-values can be correlated by... 

Subcooling in a shell-and-tube condensers. Figure 13.3 is the same propane condenser shown in Fig. 13.2. Let s assume that the pressure drop through the shell side is zero. Again, we are dealing with a pure component propane. The inlet vapor is at its dew point. That means it is saturated vapor. Under these circumstances, the outlet liquid should be saturated liquid, or liquid at its bubble point. As the inlet dew-point temperature is 120°F, the outlet bubble-point temperature should be 120°F. But, as can be seen in Fig. 13.3, the outlet shell-side liquid temperature is 90°F, not 120°F. Why ... 

Note that the propane vapor is still condensing to propane liquid at 120°F. The condensed liquid is in intimate contact with the propane vapor, as it drips off the outside surface of the colder condenser tubes. The saturated propane vapor condenses directly to saturated propane liquid at 120°F. The saturated, or bubble-point, liquid then drips from the condensation zone of the condenser into the subcooling zone of the condenser. This is the zone where the tubes are submerged in liquid. 

At pressures above the vapor pressure of propane and less than the critical locus of mixtures of methane and n-pentane, for instance 500 psia, dot 4, the methane-propane and methane-n-pentane binaries exhibit two-phase behavior, and propane-n-pentane mixtures are all liquid. Thus the saturation envelope appears as in Figure 2-28 (4). 

Liquid-liquid partition chromatography. The stationary phase consists of 1% tris(2-cyanoethoxy)propane (TCEP) on Zipax support. The mobile phase, hexane, is saturated with TCEP prior to use. A pre-column consisting of 30% TCEP on Gas-Chrom Q is used in order to prevent stripping of the liquid phase from the analytical column. The detector is set at 254 nm for monitoring the column effluent. The retention times of a number of 2,4-dinitrophenylhydrazones obtained with this system are given in Table 4.12. Gradient elution may be made with Permaphase ETH as stationary material and a gradient of hexane-chloroform. The limit of detection is ca. 5 ng per injection. 

Natural gas usually contains varying amounts of ethane, propane, butane, and higher hydrocarbons. The gas is often close to its saturation point with respect to some of these hydrocarbons, which means liquids will condense from the gas at cold spots in the pipeline transmission system. To avoid the problems caused by condensation of liquids, the dew point of US natural gas is lowered to about —20 °C before delivery to the pipeline by removing portions of the propane and butane and higher hydrocarbons. For safety reasons the Btu rating of the pipeline gas is also usually controlled within a narrow range, typically... 

The molecular weight of the mixture is 42.7. Since the MW of propane is 44, take first the enthalpy value of propane liquid at 100°F, which is 171 Btu/lb. Next take the saturated liquid enthalpy of ethane (30 MW) at 100°F, which is 200 Btu/lb. The following interpolation calculation is made. 

The liquid-phase oxidation (LPO) of light saturated hydrocarbons yields acetic acid and a spectrum of coproduct acids, ketones, and esters. Although propane and pentanes have been used, n-butane is the most common feedstock because it can ideally yield two moles of acetic acid. The catalytic LPO process consumes more than 500 million lb of n-butane to produce about 500 million lb of acetic acid, 70 million lb of methyl ethyl ketone, and smaller amounts of vinyl acetate and formic acid. The process employs a liquid-phase, high-pressure (850 psi), 160-180°C oxidation, using acetic acid as a diluent and a cobalt or manganese acetate catalyst. 

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