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Condenser pressure drop

Tube Side Condensation Pressure Drop Kem recommends the following conservative relation ... [Pg.211]

Koestel, A., M. Gutstein, and R. T. Wainwright, 1963, Fog-Flow Mercury Condensing Pressure Drop Correlation, Proc. 3rd Annual High Temperature Liquid Metal Heat Transfer Tech. Meeting, ORNL-3605, Vol. 2, 198, ORNL, Oak Ridge, TN. (3)... [Pg.541]

Figure 13 Effect of Hydraulic diameter on Condensation Pressure Drop. Figure 13 Effect of Hydraulic diameter on Condensation Pressure Drop.
Garimella, S., Agarwal, A., and Killion, J. D. (2004) Condensation Pressure Drops in Circular Microchannels, Proceedings of the Second International Conference on Microchannels and Minichannels (ICMM2004), Rochester, NY, United States, American Society of Mechanical Engineers, New York, NY 10016-5990, United States, pp. 649-656. [Pg.290]

For preliminary design, column operating pressure and type condenser can be established by the procedure shown in Fig. 12.4, which is formulated to achieve, if possible, reflux drum pressures Pp between 0 and 415 psia (2.86 MPa) at a minimum temperature of 120°F (49°C) (corresponding to the use of water as the coolant in the overhead condenser). The pressure and temperature limits are representative only and depend on economic factors. Both column and condenser pressure drops of 5 psia are assumed. However, when column tray requirements are known, more refined computations should allow at least 0.1 psi/tray for atmospheric or superatmospheric column operation and 0.05 psi/tray pressure drop for vacuum column operation together with a 5 to 2 psia condenser pressure drop. Column bottom temperature must not result in bottoms decomposition or correspond to a near-critical condition. A total condenser is used for reflux drum pressures to 215 psia. A partial condenser is used from 215 psia to 365 psia. A refrigerant is used for overhead condenser coolant if pressure tends to exceed 365 psia. [Pg.229]

This overview selectively describes only those principles of condensation that directly pertain to operation and troubleshooting of distillation condensers. This overview omits several considerations foremost for optimizing condenser pressure drop and heat transfer, and leaves their coverage to most standard heat transfer texts and review articles (e.g., 69, 187, 310, 319). Even the principles covered are discussed rather briefly the reader is referred to the cited references for in-depth treatment. [Pg.467]

Vapor entering a vertical downflow in-sbell condenser contained a hig -molecular-weig t condensable material and a low-molecular-wei t inert Poor condensation was caused by channeling that caused inert blanketing. Use sealing strips ensure adequate condenser pressure drop. [Pg.666]

Condensation in a horizontal in-shell partial condenser with liquid outlet at the bottom and vapor outlets at the top was controlled hy vaijdng liquid level in the condenser. Excessive entrainment was caused by condenser pressure drop building a large hydraulic gradient... [Pg.756]

Use a simulator to do as many of the calculations as possible, including the very important column pressure-drop calculations (because of the need for vacuum in one or more columns). Assume a condenser pressure drop of 5 kPa and no pressure drop across the reboiler. You may select column internals from the following list ... [Pg.613]

Opening the Pressure page tab (shown at the top of Fig. 11.21) permits setting pressures in the column. The pressure in the reflux drum is specified to be 39.7 psia. The condenser pressure drop is 2psi, so the pressure on Stage 2 is set at 41.7 psia. The pressure at the bottom of the column is specified to be 44.7 psia. [Pg.323]

The binary separation of methanol and water is used as an example column. A feed of 82 mol% methanol and 18 mol% water is fed to a column with 40 trays (42 stages in Aspen terminology with feed on Stage 27 and the condenser labeled as Stage 1). Condenser pressure is 1 bar, condenser pressure drop is 0.1 bar, and tray pressiue drop is 0.01 bar per tray (giving a base pressure of 1.5 bar). Product purities are 99.9 mol% methanol in the distillate and 99.9 mol% water in the bottoms. The required reflux ratio is 0.8569. Column diameter is 5.61 m. Reboiler heat input is 64.1 MW. Condenser heat removal is 60.0MW. The NRTL physical property package is used. [Pg.387]

The effect of increasing the reflux rate on a crude tower, even with a constant condenser duty, will be to increase the condenser pressure drop. This happens because the volume and the weight of the tower overhead vapors will increase as the tower-top temperature drops. At the Calumet Refinery in Shreveport, Louisiana, the crude tower reflux rate was increased by 25 percent and the tower-top temperature dropped by 50 F-60 F. The overhead condenser AP increased from about 12 to 24 psi. The tower pressure was kept constant, but the reflux drum pressure declined from 17 to 5 psig. [Pg.205]

Figure 3.10 is a plot of potential against distance from the wall for a liquid in a capillary of sufficient width for its middle A to be outside the range of forces from the wall. Since the capillary condensate is in equilibrium with the vapour, its chemical potential (=p represented by the horizontal line GF, will be lower than that of the free liquid the difference in chemical potential of the condensate at A, represented by the vertical distance AF, is brought about entirely by the pressure drop, Ap = 2y/r , across the meniscus (cf. Equation (3.6)) but at some point B. say, nearer the wall, the chemical potential receives a contribution represented by the line BC, from the adsorption potential. Consequently, the reduction Ap in pressure across the meniscus must be less at B than at A, so that again... [Pg.124]

Dust Filter. The cloth or bag dust filter is the oldest and often the most reHable of the many methods for removing dusts from an air stream. Among their advantages are high (often 99+%) collection efficiency, moderate pressure drop and power consumption, recovery of the dust in a dry and often reusable form, and no water to saturate the exhaust gases as when a wet scmbber is used. There are also numerous disadvantages maintenance for bag replacement can be expensive as well as a sometimes unpleasant task these filters are suitable only for low to moderate temperature use they cannot be used where Hquid condensation may occur they may be hazardous with combustible and explosive dusts and they are bulky, requiring considerable installation space. [Pg.403]

Fig. 3. Solvent-processing equipment using partial condenser. Level a on the water overflow line to the receiver should be about 3 cm below level b on the solvent-return line. Dimension b—c must be great enough to overcome pressure drop in the vapor piping, condenser, solvent piping, and rotameter. In a 4 m (1000-gaI) ketde, dimension b—c would be at least 1.25 m. The volume of the piping described by the dimension c—d—e should contain twice the volume of dimension b—c, thus providing an adequate Hquid seal against normal ketde operating pressures. Fig. 3. Solvent-processing equipment using partial condenser. Level a on the water overflow line to the receiver should be about 3 cm below level b on the solvent-return line. Dimension b—c must be great enough to overcome pressure drop in the vapor piping, condenser, solvent piping, and rotameter. In a 4 m (1000-gaI) ketde, dimension b—c would be at least 1.25 m. The volume of the piping described by the dimension c—d—e should contain twice the volume of dimension b—c, thus providing an adequate Hquid seal against normal ketde operating pressures.
The high T] values above conflict with the common behef that distillation is always inherendy inefficient. This behef arises mainly because past distillation practices utilized such high driving forces for pressure drop, tedux ratio, and temperature differentials in teboilets and condensers. A teal example utilizing an ethane—ethylene sphtter follows, in which the relative number for the theoretical work of separation is 1.0, and that for the net work potential used before considering driving forces is 1.4. [Pg.84]

Tower Internals and Equipment Modification. Tower capacity expansion can be achieved through the use of random or stmctured packing, or through the use of higher capacity trays such as the UOP multiple downcomer tray. Packing has been used in the gasoline fractionator, water quench tower, caustic and amine towers, demethanizer, the upper zone of the deethanizer, debutanizer, and condensate strippers. Packing reduces the pressure drop and increases the capacity. [Pg.442]

For condensing vapor in vertical downflow, in which the hquid flows as a thin annular film, the frictional contribution to the pressure drop may be estimated based on the gas flow alone, using the friction factor plotted in Fig. 6-31, where Re is the Reynolds number for the gas flowing alone (Bergelin, et al., Proc. Heat Transfer Fluid Mech. Inst., ASME, June 22-24, 1949, pp. 19-28). [Pg.655]

Baffles in a horizontal in-shell condenser are oriented with the cuts vertical to facilitate drainage and eliminate the possibility of flooding in the upward cross-flow sections. Pressure drop on the vapor side can be estimated by the data and method of Diehl and Unruh [Pet. Refiner, 36(10), 147 (1957) 37(10), 124 (1958)]. [Pg.1042]

Some judgment is required in the use of these correlations because of construction features of the condenser. The tubes must be supported by baffles, usually with maximum cut (45 percent of the shell diameter) and maximum spacing to minimize pressure drop. The flow of the condensate is interruptea by the baffles, which may draw off or redistribute the liqmd and which will also cause some splashing of free-falling drops onto the tubes. [Pg.1042]

For subcooling, a liquid inventory may be maintained in the bottom end of the shell by means of a weir or a hquid-level-controUer. The subcoohng heat-transfer coefficient is given by the correlations for natural convection on a vertical surface [Eqs. (5-33 ), (5-33Z )], with the pool assumed to be well mixed (isothermal) at the subcooled condensate exit temperature. Pressure drop may be estimated by the shell-side procedure. [Pg.1042]

Pressure drop during condensation inside horizontal tubes can be computed by using the correlations for two-phase flow given in Sec. 6 and neglec ting the pressure recoveiy due to deceleration of the flow. [Pg.1042]

Pressure drop on the condensing side may be estimated by judicious application of the methods suggested for pure-component condensation, taking into account the generally nonlinear decrease of vapor-gas flow rate with heat removah... [Pg.1043]


See other pages where Condenser pressure drop is mentioned: [Pg.85]    [Pg.329]    [Pg.338]    [Pg.279]    [Pg.127]    [Pg.607]    [Pg.444]    [Pg.368]    [Pg.329]    [Pg.338]    [Pg.224]    [Pg.85]    [Pg.329]    [Pg.338]    [Pg.279]    [Pg.127]    [Pg.607]    [Pg.444]    [Pg.368]    [Pg.329]    [Pg.338]    [Pg.224]    [Pg.403]    [Pg.411]    [Pg.496]    [Pg.502]    [Pg.99]    [Pg.473]    [Pg.479]    [Pg.175]    [Pg.477]    [Pg.478]    [Pg.655]    [Pg.655]    [Pg.923]    [Pg.1041]    [Pg.1042]    [Pg.1042]   
See also in sourсe #XX -- [ Pg.723 ]

See also in sourсe #XX -- [ Pg.884 ]




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