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

4

PR-Panta Ring™

5

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%

18

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

20

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