Bubble Tray Hydraulics

Davies, Jamie A.

doi:10.1021/ie50450a013

Cited by 11 publications

(1 citation statement)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The tray type-i.e., single cross-flow, double cross-flow, triple cross-flow, rim and center, double rim and center, step-down, etc.-and cap size and spacing are selected after a careful study of the tray hydraulics and the stability of the tray from the standpoint of liquid gradient. The most comprehensive mathematical analyses of these two factors are given by Good, Hutchinson, and Rousseau (9) and Davies (5), who set forth in detail the calculations involved in evaluating a deck for these factors and designing a deck suitable from these standpoints. 5.…”

Section: Oil Heating Unitmentioning

confidence: 99%

Vacuum Distillation of Petroleum Residues

Kraft¹

1948

Ind. Eng. Chem.

View full text Add to dashboard Cite

Section: Oil Heating Unitmentioning

confidence: 99%

Vacuum Distillation of Petroleum Residues

Kraft¹

1948

Ind. Eng. Chem.

View full text Add to dashboard Cite

Distillation

2022

Petroleum Refining Design and Applications Handbook

View full text Add to dashboard Cite

The effect of vapor distribution on distillation plate efficiencies

Furzer

1969

AIChE Journal

View full text Add to dashboard Cite

The nonuniform distribution of vapor across a distillation plate causes a reduction in the Murphree plate efficiency. The magnitude of the reduction has been evaluated and the maximum effect occurs when the liquid mixing is intermediate between the perfectly mixed and the plug flow cases.The AlChE bubble-tray design manual ( 1 ) provides a method for calculating the Murphree plate efficiency (EMv) for binary systems for uniform vapor distribution across the plate. One of the causes given for the predicted efficiency bein below the measured value is a poor vapor liquid gradients, poor inlet arrangements and weir location. The numerous studies on the hydraulic gradient (2 to 6) all stress the reduction in vapor velocity through the plate near the liquid downcomer and higher vapor velocities near the discharge weir.A simple vapor distribution function such as a linear function agrees well with Bolles calculations (2). Let u be a dimensionless vapor mass flow rate defined by distribution. T a is can arise from a poor tray design, high where z is the distance to a int on the plate and Z is the total length of the plate E nwhere b = BZ/2Va, where 0 < b < 1 and B is the vapor velocity gradient across the plate. The value of b is restricted to the range 0 to 1 which allows for positive values of u throughout the plate, and a minimum positive velocity gradient of zero when the vapor is uniformly distributed. MURPHREE PLATE EFFICIENCYThe Murphree plate efficiency is defined by where yav is the average vapor composition leaving the plate, y n + l is the vapor composition entering the plate, yon is the vapor composition in equilibrium with the liquid leaving the plate. The average vapor composition leaving the plate is given Substituting from Equations (1) and (2) Substituting yav from Equation ( EOG For a uniform vapor distribution b = 0 then u = 1 and which is in agreement with (7). To evaluate the integral in Equation (10) the dimensionless composition distribntion must be known, and this will depend on the degree of liquid mixing on the plate. EDDY DIFFUSION M O D E LThe liquid mixing by an eddy dispersion model which assumes that the rate of back mixing is proportional to the concentration gradient on the plate is described in the manual (1 ) . A mass balance for the more volatile comonent over a vertical element of width dz has been given ! o r constant plate width and constant point efficiency by

show abstract

Bubble Tray Hydraulics

Cited by 11 publications

References 2 publications

Vacuum Distillation of Petroleum Residues

Vacuum Distillation of Petroleum Residues

Distillation

The effect of vapor distribution on distillation plate efficiencies

Contact Info

Product

Resources

About