Welded Plate Heat Exchangers

engineering for a better world

Welded Plate Heat Exchangers

33 GEA Group Aktiengesellschaft

High heat transfer ratio

Compact design

Fully accessible plate pack

Easy maintenance


Installation examples


Refineries

Renewable energy

Vegetable oil

Chemical industry

Oil & gas industry


Agenda

GEA Group – a strong back

GEA PHE – Energy saving product variety

Energy saving – case studies and advantages


Save energy and emissions


In times of increasing demand for environmental requirements accompanied by

the threat of low margins and strong global competition, energy efficiency

becomes an evident need.

Heat exchanger technology can contribute to achieve this target.

Transfer heat efficiently by using appropriate heat exchanger technology

Maximize performance of heat exchangers

Recover the existing heat by optimzing processes

Reduce maintenance and service costs


Reasons for PHE growth


Process Plant Energy Efficiency

Capable of temperature cross

Various technologies available for different applications

Better and better history

Reduced service & maintenance costs

Small footprint

Short Pay-back time


Comparison with Shell & Tube


Operating limits for different types of Heat Exchangers

gasketed

PHE/LWC

brazed PHE

GEABloc

shell and tube heat exchanger

Design

temperature [°C]

Design pressure [bar]

25

40

-100

-50

-40

180

250

400

GEAFlex

100

900


Comparison PHE vs Shell & Tube


0,0% 10,0% 20,0% 30,0% 40,0% 50,0% 60,0% 70,0% 80,0% 90,0% 100,0%

Fluid content

Heat transfer area

Operating weight

Installation space

Manufacturing costs

Fouling coefficients

Cleaning time

S&T

GPHE


Heat Transfer: U-Value vs LMTD


Example :

ΔT hot side: 20°C (36°F)

ΔT cold side: 20°C (36°F)

Q: 500 kW (1.7 MBTU/h)

Max ΔP = 70 kPa ~10 PSI S&T

PHE

0

200

400

600

800

1000

1200

1400

1600

1,8 3,6 5,4 9 18 36

U-V

alu

e (B

TU/f

t² °

F)

LMTD (°F)

U-Value vs LMTD

U decreases rapidly with decreasing LMTD


Reasons for PHE efficiency: Turbulence


High Turbulence due to corrugation

Turbulence enhances heat transfer

Self-cleaning effect to minimize fouling

High Shear Stress

3 to10 times higher than in S&T


Reasons for PHE efficiency: Temperature cross


Temperature

Cross

Temperature

Approach

T

A


Interchanger


Interchanger Heater Cooler Processing

Feed

Hot process fluid

Recover heat from process

Save energy from heater

Reduce cooling water consumption

Requires heat exchanger capable of temperature cross!


Comparison PHE vs Shell & Tube


Type Shell & Tube HE Plate HE

Heat transfer area 3 x 1 x

Heat transfer ratio

(U or k value) 1 2 to 5

Fluid Volume 5x 1x

Shear stress 5-20 Pa 20-100 Pa

Temp. approach 5°C (9°F) 1°to 2°C (1.8°– 3.6°F)

Temp. cross NO YES

Heat Recovery Low High

Design Pressure high < 450 psig (32 barg)

Design Temperature high 150° to 350°C

Why should you switch from a shell & tube HE to a Plate HE ?


Case Study: Interchanger


Str

ipp

er

Flash

Drum

Ab

so

rbe

r

Lean Amine

exchanger

Lean/rich

interchanger

Overhead

condenser

Reboiler

Acid gas


Case Study: Temperature cross


Amine Regenerator Feed/Effluent Exchanger

Hot Side Cold Side

Fluid type Lean Amine Rich Amine

Temp. In 127,7°C 67,7°C

Temp. Out 93,3°C 107°C

Mass flow 77800 kg/h 80850 kg/h

All. ΔP 35 kPa 35 kPa

Temperature Cross!


Case Study: Design results


S&T option GEABloc choice

2m

5,6m

1,25m

0,8m

GEABloc-3d-animation.wmv


Case Study: Comparison


Amine Regenerator Feed/Effluent Exchanger

S&T PHE

No. of HX 2 in series 1

Surface Area 2 x 111m2=222m2 40m2

Pressure drop 22kPa / 17kPa 28kPa / 31kPa

OHTC clean 1180 W/m2K 3200 W/m2K

Shear Stress 14 Pa / 11 Pa 35 Pa / 39 Pa

Weight dry 2 x 3800kg 2230kg

Weight flooded 2 x 5500kg 2500kg

Length 5.6m 1.0m

Height 2 x 1m=2.0m 1.25m

Foot print 5.6m2 1.0m2

Price 90 000€ 35 000 €

Savings

-80%

all. ΔP=35kPa

-70%

+250% / +350%

-70%

-80%

-80%

-60%


Vertical Condenser


Vapor

Condensate

Multiple passes on condensing side

Higher condensate channel velocity

Higher heat transfer coefficient

Smaller heat exchanger size


Case Story: Braskem, Brazil


Polyethylene and Polypropylene plant

Two working heat exhcnagers had to

be replaced during turn-around.

Condenser and sub-cooler were install-

ed on top of column.

One GEABloc replaced two existing

heat exchangers with

Smaller footprint

Less maintenance

Lower CAPEX


Case Study: Essar, India


Heat recovery from heavy naphtha

In original installation Heavy Naphtha was sent to Fin Fan Cooler.

Energy was wasted to air!

Propose welded plate heat exchanger suitable for high pressure

application. Duty is to cool, down heavy naphtha from 188°C to 58°C

using 74 t/h Boiler Feed Water (from 105 to 150°C).

Heat recovery 3.33 GCal/h

Approximate cost estimate : Euro 100,000

Estimated savings : Euro 0.85 Million per yr* (* 1MT MP Steam = euro 20)

Payback period : ca. 2 Month


Case Study: Crude Pre-heating Refinery, Russia


Atm

ospheric C

olu

mn

Gas & Gasoline – 50°C

Kerosene – 190°C

LGO – 270°C

MGO – 310°C

Atm. Residue – 360°C

Crude Oil – 10°C

Pre-heated Crude– 250°C

Atmospheric

furnace

360°C

Date post:	08-Dec-2021
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Welded Plate Heat Exchangers

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