PHE 1 general (plate heat exchanger)

PHE General

Flow principle and parts

The Gasketed Plate Heat
Exchanger
– The PHE –

• The function of the plate pack – Single pass:

1


PHE General

The Gasketed Plate Heat
Exchanger
– The PHE –

• The function of the plate pack – Multi pass:

The Gasketed Plate Heat
Exchanger
– The PHE –
• The plate corrugation has two
functions:

Mechanical

Flow dynamic

2


PHE General

The Gasketed Plate Heat
Exchanger
– The PHE –

• Two plate corrugations L and H:

L: Low theta

H: High theta

The Gasketed Plate Heat
Exchanger
– The PHE –

• Two plate corrugations may form three
different interplate channels:

L + L = L channels

H + H = H channels

L + H = M channels

3

PHE General

PHE groupings influence on
performance
Example
•
•
•
•

Product: 5 000 kg/h raw milk, inlet temp 20º C
Service: 15 000 kg/h water, inlet temp 1º C
PHE:
Clip-6RM with 17 plates = 2,75m²
Channels:
Low, high and mixed theta

Parallell grouping
Example 1 * 8

1*8

4


PHE General

PHE groupings influence on
performance

• Low pressure drop
• Low heat transfer
Grouping

Temp
program, ºC

Pressure k-value, Heat
drop, kPa W/m², ºC transfer, kW

1 * 8 L
1 * 8 L

20 ! 9.0
4.4  1

3
21

1860

60

1 * 8 H
1 * 8 H

20 ! 6.0
5.4  1

12

105

2980

76

1 * 8 MH 20 ! 7.7
1 * 8 ML 4.8  1

5
45

2280

67

Series grouping
Example 8 * 1

8*1

5


PHE General

PHE groupings influence on
performance
•High pressure drop
•High heat transfer

Grouping

Temp
program, ºC

Pressure
drop, kPa

k-value,
W/m², ºC

Heat
transfer, kW

8 * 1 L
8 * 1 L

20 ! 2.5
6.5  1

1090
9450

6180

96

8 * 1 H
8 * 1 H

20 ! 1.6
6.7  1

5750
49500

8690

101

8 * 1 MH
8 * 1 ML

20 ! 1.9
6.6  1

2400
19700

7370

99

Combined grouping (symmetric)
Example 4 * 2

4*2

6

PHE General

PHE groupings influence on
performance

Grouping

Temp
program, ºC

Pressure
drop, kPa

k-value,
W/m², ºC

Heat
transfer, kW

4 * 2 L
4 * 2 L

20 ! 4.0
6.0  1

140
1210

4260

87

4 * 2 H
4 * 2 H

20 ! 2.4
6.5  1

740
6350

6300

96

4 * 2 MH
4 * 2 ML

20 ! 3.2
6.2  1

315
2580

5150

92

Combined grouping (asymmetric)

Example 4 * 2

2*4

7


PHE General

PHE groupings influence on
performance

Grouping

Temp
program, ºC

Pressure
drop, kPa

k-value,
W/m², ºC

Heat
transfer, kW

4 * 2 L
2 * 4 L

20 ! 4.8

5.7  1

140
160

3670

83

4 * 2 H
2 * 4 H

20 ! 3.1
6.3  1

740
815

5280

93

4 * 2 MH
2 * 4 ML

20 ! 3.9
6.0  1

315
340

4390

88

8


PHE General

Milk pasteurization
Parameters
•
•
•
•
•
•
•
•
•

Capacity
Temp programme; in, out, past
Running costs
Running times
Separation, temperature, skimming
Homogenisation, temperature, pressure
Deaeration, temperature, temperature drop
Heating media, cooling media

Drainability

Milk pasteurization
Heat Recovery
•
•
•
•
•
•
•

Capacity
Running hours
Cleaning intervals
Media costs
Product costs
Maintenance
Capital cost

+
+
+
+
-

9


PHE General

Heat Recovery
Product
inlet
Pasteurisation
temperature
IW

A

Cooler

B

C

Regenerative

D

HW

C

B-A
C-A

Heat recovery =

Example:

Heater

A = 4°C
B = 67°C
C = 74°C

x 100 (%)

67 - 4
74 - 4

x 100 =

63 x 100 = 90 %
70

Heat Recovery
Milk Pasteurizer
80000
70000
60000

EUR

50000
Series1

40000

Series2

30000
20000
10000
0
75

80

85

90

95

100

Regenerative

10