FLOW PATTERN
a good length of liquid path
a very long liquidpath
high liquid–vapor ratios
FLOW PATTERN
• Cross flow • Double pass
SINGLE PASS
DOUBLE PASS
DOWN COMERS AND WEIRS
WEIR
• Straight Horizontal
• Adjustable
• Notched
DOUBLE PASS SLOPPED DOWNCOMERS
MECHANICAL SUPPORTS
MANWAY
TRAY HYDRAULICS
CAPACITY GRAPH FOR A TYPICAL BUBBLE-CAP TRAY
FLOW REGIMES
CLOSE-UPS
• Cellular foam • Froth (Operating regime)
CLOSE-UPS• Emulsion regime • Froth regime
TRAY EFFICIENCY
Overall efficiencyac
eqo N
NE
21010 log044923.0log27511.052782.0 oE
Efficiency correlation (O’Connell, 1946)
MURPHREE EFFICIENCY MODEL
Thus,
inout
inoutMV yy
yyE
*
inout
inoutML xx
xxE
*
1234 xxxxxout
It is possible to have
outout yy *
1MVE
SIEVE TRAY LAYOUT• Net area
• Hole area
• Active area
LIQUID PRESSURE HEADS ON SIEVE TRAY
dugradcrestweirpdc hhhhhh
PRESSURE HEADS ON BUBBLE CAP TRAY
COLUMN DIAMETER
v
vLflood Ku
2.0
20
sbCK
floodop ufractionu )( 3600netv
vop A
MWVu
4
)( 2DiaAnet
3600)(
4
floodv
v
ufraction
MWVDia
EstimatesbC
L
v
v
Llv W
WF
fromsbC VS
Capacity factor versus flow parameter
ADIOS!• All of the references are provided during
class lectures.
• All of the pictures are taken from various books and Websites solely for educational purpose.
• The author is thankful to Dr, Syeda Sultana Razia, associate professor, ChE, BUET, for developing the core concept of this presentation.
