Post on 12-Mar-2018
PROCESS VESSEL INTERNALS
PACKED TOWER INTERNALSHeadquarter Office : No. 192, Darya blv. Saadat Abad ,Tehran, IranTel : +98 21 88370266 , Fax : +98 21 88370267
Manufacturing Headquarter: Safadasht Industrial Zone,Tehran, Iran, Tel : +98 21 65439160-3w w w . p a n t a n . c o , i n f o @ p a n t a n . c o
PROCESS VESSEL INTERNALS
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PANTAN certified according to ISO 9001:2015 forDesigning and Manufacturing of Process Vessel Internals. Our principal focus is on improvingproducts quality and customer satisfaction.
Packed Columns play an important role in distillation, absorption and stripping processes.This brouchure provides the information of the key design andspecification of column packings and packed columninternals including :
• Random Packing• Structured Packing• Liquid Distributor• Collector/Chimney Tray• Support Grid• Hold down Grid
QUALITY CHANGES THE WORLD
PROCESS VESSEL INTERNALS
PANTAN is a well-established leading designer andmanufacturer of a complete range of Process Vesselinternals for the Oil, Gas and Petrochemical Industries.
For well over a decade now, our company has developed a comprehensive range of products and services including :• Fractionation Trays• Packed Tower Internals• Separator Internals • Reactor Internals • Site Services
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Packed Tower Internals
A packed bed provides a mechanism for mass or heattransfer through which the gas and liquid phasesusually flow counter currently in the column.The presence of tower packing elements providesa resistance to the flow of these fluids that is greaterthan it would be in an empty column shell.The modification of existing mass transfer columns with modern column packings can increase the numberof available mass transfer stages.These additionalstages permit greater product recovery through areduction in losses of product in recycled or wastestreams.
Packings are divided into two main categories;Random or Dumped packing: These are discretepieces of packing with a specific geometrical shape which are randomly packed into the column.Structured packing: These are corrugated sheets of thin gauge metal or wire gauze which are suppliedin segments to form the packed bed.
Column Packing
• Low pressure drop• Operation flexibility• Capacity enhancement• Availability of materials with high resistance against corrosive services
Because of these outstanding advantages, substitutionof existing trays by new packings can be the firstapproach for revamping of mass transfer processes to gain additional capacity or efficiency requirement.
Features
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Random Packing
This type of packing is available in a multitude ofgeometrical shape which are dumped in the tower,the higher capacity is achievable with larger packing butlower separation efficiency. Optimal design and performance of a packed bed is
RR-PantaRing™ has cylindrical design and is the first generation of random packings, well known asRaschig Ring.
Carbon Rings as one of the most common and generictype of packings provides a corrosion resistance ,thermalshock resistance, and high temperature stability conditions.
• Carbon Ring
RR-Panta Ring™
• Metal Ring
Nominal Size(mm)
Equivalent Size(inch)
# 25
# 40
# 50
1”
1 ½ “
2 “
Bulk Density(kg/m3)
Quantity(pieces/m3)
Surface Area(m²/m³)
400
245
320
50000
14500
6500
220
130
110
achieved by selecting a packing that optimizes the totalgas to liquid interface with a low pressure drop PANTANmanufacture a comprehensive range of packing withmultitude geometrical shape and material of constructionfor almost every application.
Nominal Size(mm)
Equivalent Size(inch)
# 25
# 40
# 50
1”
1 ½ “
2 “
Quantity(pieces/m3)
Surface Area(m²/m³)
45000
14000
5800
Bulk Density(Kg/m3)
520
510
380
175
125
92
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PR-Panta Ring™
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This second generation of random packings is well known as Pall Ring which is one of the most commontype of packings media.
• Features• Most experienced random packing in industries and research institutes• Improved strength by proper material thickness• Lower pressure drop rather than Raschig Rings
• Features• 30% lower pressure drop rather than Pall Rings• More efficiency and capacity rather than other random packings• Minimum liquid hold up
• Well surface utilization in transfer phenomena• Shorter packed bed height.• Outstanding mechanical strength
This 3rd generation of random packing media designedto give enhanced capacity and increased efficiencyover the older style Pall Ring packing.This type of packing combines the high void fraction and the well-distributed surface area of the Pall Ringwith the low aerodynamic drag of the saddle shape. This kind of random packing is used widely in separationcolumns. By comparison to the PR Series, PantaRing™ IR series provides a more open shape and improvedliquid spread, also produce adequate mechanical strength resistance. This type is a direct replacement of well known IMTP packing.
IR-Panta Ring ™
Nominal Size(mm)
Equivalent Size(inch)
1”
1 ½ “
2 “
Bulk Density(kg/m3)
Quantity(pieces/m3)
Surface Area(m²/m³)
385
250
210
51000
14400
6600
195
135
105
# 25
# 40
# 50
Nominal Size(mm)
Equivalent Size(inch)
1”
1 ½”
2”
2 ¾”
Bulk Density(kg/m3)
Quantity(pieces/m3)
Surface Area(m²/m³)
270
230
140
110
130000
46000
14000
4500
230
145
100
60
# 25
# 40
# 50
# 70
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Structured Packing
Panta PakTM Structured Packing is formed from corrugated thin sheet metal in a crisscrossing way and intersections to create vapor flow channelsand mixing points for liquid and vapor phase. Structured packing is ideal for difficult separations requiring a large number of theoretical stages,in lowliquid rate absorption/stripping systems or applications that require a wide operating range such as vacuumand atmospheric crude oil fractionators, FCC mainfractionators and TEG contactors meanwhile it causeslower pressure drop than random packing.Panta PakTM is a typical structured packing formed from corrugated sheets of perforated embossed metal[PS series] or wire gauze [PG series].
Panta Pak™ "PS" Series
An industry standard sheet metal which is available with specific surface ranging from below 125 m2/m3
for high capacity to more than 750 m2/m3 for highefficiency applications. The standard angle of thecorrugations which is 45°[referred M1] and 60°[referred M2]also high capacity structured packing [referred MH] are fabricated in PANTAN. Metal Structured Packingprovides high capacity, low pressure drop and goodwettability in many process columns.
• Features• Ideal for vacuum services• Very low liquid loads (< 100 L /m2h) are possible• Low pressure drop per theoretical stage• High separation efficiency owing to larger mass
transfer area• Good wettability of the packing surfaces• Superior compressive strength
Panta PakTM "PG" Series
This type of Structured Packing is made of mesh type gauze woven by metal wire and is mainly used toenhanced separation characteristics for fine chemicals, perfumery, and pharmacy.It is normally manufactured with very high surface area [500 m2/m3 and 750 m2/m3]
• Features• Superior wetting ability owing to capillarity• High separation efficiency /High number of theoretical stages• Lower specific pressure drop• Small liquid hold-up
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Panta-Pak
PS-125M1
PS-125M2
PS-165M1
PS-165M2
PS-175M1
PS-175M2
PS-225M1
PS-225M2
PS-250M1
PS-250M2
PS-250MH
PS-300M1
PS-300M2
PS-500M1
PS-500M2
PG-500M2
PS-750M1
PG-750M1
125
125
165
165
175
175
225
225
250
250
250
300
300
500
500
500
750
750
45˚
60˚
45˚
60˚
45˚
60˚
45˚
60˚
45˚
60˚
45˚
45˚
60˚
45˚
60˚
60˚
45˚
45˚
2.05
4.05
1.5
2.35
1.25
1.85
1.1
1.65
1
1.55
1
0.9
1.2
0.7
0.9
0.8
0.6
0.33
Corrugation Angle Relative HETPSurface Area(m²/m³)
800
700
600
500
5
300
200
100
00.00 0.02 0.04
Vapor Rate,Cs(m/s)
Pres
sure
Dro
p,Δ
P (p
a/m
)
0.06 0.08 0.10 0.12
800
700
600
500
5
300
200
100
00.00 0.02 0.04
Vapor Rate,Cs(m/s)
Pres
sure
Dro
p,Δ
P (p
a/m
)
0.06 0.08 0.10 0.12
800
700
600
500
5
300
200
100
00.00 0.02 0.04
Vapor Rate,Cs(m/s)
Pres
sure
Dro
p,Δ
P (p
a/m
)
0.06 0.08 0.10 0.12
Panta Pak TM PS-250 M2 Structure PackingPressure Drop Data
Liquid Rate 75 m3/m2h 50 m3/m2h 25 m3/m2h 15 m3/m2h 0 m3/m2h
Panta Pak TM PS-250 M1 Structure PackingPressure Drop Data
Panta Pak TM PS-250 MH Structure PackingPressure Drop Data
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• Flooding curves for Panta PakTM structured packing
• Relative capacity & HETP for Panta PakTM structured packing
Note: Relative capacity and HETP are for estimation purposes only and may vary according to actual column loads and duty.
1
0.1
0.01
4.5
3.5
2.5
1.5
0.5
PS-125 M1PS-125 M2
PS-250 M1PS-250 M2
PS-250 MHPS-500 M1
PS-500 MH0
4
3
2
1
0 0.02 0.04Flow Parameter
Vapo
r Ra
te(m
/s)
0.06 0.08 0.1
PS-500M1PS-250M1PS-125M1
Relative CapacityRelative HETP
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Hydraulic Design
Generalized pressure drop correlation(GPDC) is a commonmethod for estimating pressure drop and maximum capacity of most generic random packings.Pressure drop estimated by using this model is accurateto within ±20% for most random packing styles.
The optimum efficiency and loading point areevaluated by using reliable design models, for selectedrandom or structured packing the bed heights are determined from HETP (height equivalent theoreticalplate) and the column diameter is determined from capacity and pressure drop.
HETP as Packing Efficiency is determined to evaluaterequired height of packing to achieve specified numberof theoretical equilibrium stages.Basic data such as number of theoretical stages,liquid-vapor loads and physical properties are derivedfrom standard process simulation software.There are some direct parameters for HETP calculationsuch as liquid-vapor loads, physical and transportproperties, packing type-size as well as indirect factors like liquid-vapor distributor quality.Proper liquid distribution is the key parameter in order to achieve optimum performance with any highefficiency random or structured packing.Below curve shows a typical HETP versus vaporrates of typical packing.
PANTAN packed bed hydraulic design software notonly consists of tried and tested correlations forHETP, pressure drop, Flooding, liquid hold up andetc but also contains a sufficient data bank of variousexperienced cases to check the design output.
Packing Efficiency
Packing Pressure Drop
Pressure drop for structured packing is calculatedby related GPDC for rough estimation or by correlationsand experimental data for more accurate evaluation.
0.01 1
Generalized Pressure Drop Correlation for Random Packing
0.1Flow Parameter,X
0.00
0.05
0.10
0.15
0.20
C s2 .F.f
0.25
0.30
0.35
0.40
Vapor Rate
HE
TP
Flood Point
EfficientCapacity
System BaseHETP
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Packed Tower Internals
Packed columns including both random and structuredpacking must have several compatible internal componentsto function properly. Reliable design and selection of internals including liquid distributors, collectors / chimney
• Packed Column Internals Layout
tray, support grid and hold down grid/ bed limiter is essential for gaining the specific service requirements.PANTAN has valued experiences in design, selection and manufacturing the packed column internals.
Reflux
Feed
ReboilerVapor
Vapor Distributor
Liquid Feed Pipe
Liquid Distributor
Bed Limiter
Packing
Packing
Support Grid
Support Grid
Liquid Re-distributor
Bed Limiter
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Model TD-111
Liquid Distributor
To acquire the maximum efficiency in packed column,liquid should be distributed uniformly over the packedbed.Therefore, Liquid Distributors are used above each bed of packing.Good practice designed distributorshave following specifications:• Uniform liquid distribution• Operation flexibility through the turn down range
• Low vapor pressure drop• Low liquid residence time• Capability to be used as combined with collector for re-distribution• Minimum distributor height• Fouling resistance• Cross mixing capability
Type
Diameter
Irrigation Rate
Resistance to Fouling
Turndown Ratio
Holes Position
Drip points Density
Drip Tube Trough Distributor
>1000 mm
0.8 – 30 m3/ h m2
High
2:1 (maximum 10:1 in multiple level holes)
Square pattern punched in the trough’s side which is covered with drip tubes (Multiple levels & series of holes can be punched to achieve high turndown ratio)
80 - 100 drip points /m2
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Model TD-112
Type
Diameter
Irrigation Rate
Resistance to Fouling
Turndown Ratio
Holes Position
Drip points Density
Drip Panel Trough Distributor
>900 mm
> 30 m3/ h m2
Medium
3:1
80 - 200 drip points /m2
Model PD-121 / PD-122
Type
Diameter
Liquid Range
Resistance to Fouling
Turndown Ratio
Holes Position
Drip points Density
Optional Features
Orifice Pan Distributor
300 – 1000 mm
2.5 - 75 m3/ h m2
Low
2:1
Square or triangular pattern punched in the pan floor
60 - 100 drip points / m2
Combined with hat to operate as re-distributor
• PD-121 • PD-122
Square pattern punched in the trough’s side which is covered with drip Panel
Type
Diameter
Liquid Range
Resistance to Fouling
Turndown Ratio
Holes Position
Drip points Density
Optional Features
Bottom Orifice Deck Distributor
> 300 mm
> 30 m3/ h m2
Low
2:1
Square pattern punched in the deck
70-100 Drip points /m2
Combined with Hat to Operate as Re-distributor
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Type
Diameter
Irrigation Rate
Resistance to Fouling
Turndown Ratio
Holes Position
Drip points Density
Optional Features
Drip Tube Deck Distributor
>1000 mm
0.8 – 30 m3/ h m2
Medium
2 :1 (10:1 max in multiple levels holes)
Square pattern punched in the trough side which is covered with drip tubes (Multiple levels & series of holes can be punched to achieve high turndown ratio)
80-200 Drip points /m2
Combined with Hat to Operate as Re-distributor
Model DD-131
Model DD-132
Type
Diameter
Liquid Range
Resistance to Fouling
Turndown Ratio
Holes Position
Feature
Pipe Arm Distributor
> 400 mm
4-25 m3/ h m2
Low (can be used only for clean services)
2:1
Orifices furnished in pipe below
Suitable for Low irrigation rate and limited height space services
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Model AD-141
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Liquid Collector/ Chimney Tray
Liquid Collector/Chimney tray is used in the columnsto achieve one or more of following purposes:• Vapor distribution• Liquid collection from above bed and conduction to below distributor• Total or partial liquid draw-off
Open area, allowable pressure drop, height of collectorliquid & vapor loads, column diameter and quantityof Liquid draw-off are the main parameters in collectordesign.
Model VC-211
Model CC-221
Type
Diameter
Service
Open Area
Vane Collector
> 800 mm
Suitable for vacuum services because of low pressure drop (high vapor & low liquid loads)
50-80%
can be used as a part of combined distributor/collector for re-distributing liquid between packed bedsFeatures
Type
Diameter
Service
Open Area
Rectangular Chimney Tray
All diameters
Suitable for large columns total or partial liquid draw-off as seal welded
15-30%
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Model CC-222
Type
Diameter
Service
Open Area
Circular Chimney Tray
All diameters
Suitable for large columns total or partial liquid draw-off as seal welded- Usable for vapor distribution
15-30%
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Support Grid
Packings are installed on support grids which aredesigned to provide sufficient strength to support packed beds under normal operating conditions without creating any capacity restriction in the column.
Model SG-311
Model SG-321
Type
Diameter
Service
Structure Packing Support Grid
All diameters
Support sheet metal or wire gauze structured packing
Type
Diameter
Service
Random Packing Support Grid
All diameters
Support Random packing media
Criteria for selecting a support grid include :• Type of packing (random or structured)• Maximum design load
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Hold Down Grid
Hold Down Grid / Bed Limiter for random packing isused because vapor load has potential for moving thepacking media.When top packing layers top have potential of upward
Model HG-411
Model HG-421
displacement in the structured packing, Hold Down Grid is recommended.Where the upward displacementof structured packing is not a concern, the distributorover the packed bed can alsobe used as bed limiter.
Type
Diameter
Service
Structured Packing Hold Down Grid
All diameters
Retain the sheet metal or wire gauze structured packing
Type
Diameter
Service
Random Packing Hold Down Grid
All diameters
Retain the Random packing media
LIQUID COLLECTOR
LIQ
UID
DIS
TRIB
UTO
R
HOLD DOWN GRID
HOLD DOWN GRID
PAC
KED
TO
WER
INTE
RNA
LSLI
QU
ID C
OLL
ECTO
R C
HIM
NEY
TR
AY
RANDOM PACKING
STRUCTURED PACKING STRUCTURED PACKING
PR-P
AN
TARI
NG
™
PACK
ING
EFF
ICIE
NCY SUPPORT GRID
RA
ND
OM
PA
CK
ING
SUPPORT GRID
PROCESS VESSEL INTERNALS
CHIMNEY TRAY
LIQUID COLLECTOR/ CHIMNEY TRAY
IR -PANTARING ™BED
LIM
ITER
PANTA-PAK™
PANTA-PAKTM