Humidification products
Steam injection humidifiers
ISO 9001
Maximum
450
630
900
1 200
1 470
1 780
2 080
2 380
2 690
3 000
3 300
3 610
3 950
Minimum
280
450
630
900
1 200
1 470
1 780
2 080
2 380
2 690
3 000
3 300
3 610
Lance model 1
1.5 2 3
4 5
6 7 8 9
10 11 12
8.1.3
0
0
0
0
0
6
10
15
20
22
18
30
45
60
66
24
40
60
80
88
30
50
75
100
110kg/h
110
36
60
90
120
132
12
20
30
40
44
TI-P795-02
CH Issue 4
Cert. No. LRQ 0963008
Type 20 and Type 40
Sizing
Direct Steam Injection Humidifiers
Product selection
The best diffusion of steam into the air flow is achieved by spreading the outlet nozzles of the lance(s) evenly within the duct, vertically
and horizontally.
This is achieved by following the example through the five steps below.
Step 1 - The known data
Duct size
Steam pressure
Required maximum
steam flowrate
Spirax Sarco valve connection
Valve actuation
Actuator voltage
Control signal
Step 3 - Select the lance model
Step 2 - Select the lance
1 800 mm high
and 1 800 mm wide
1.5 bar g
110 kg/h
Screwed
Electric
24 Vac 50 / 60 Hz
VMD
Select the recommended number of lances required from Table 1 to
match the known duct height.
Duct height in mm
up to 1 000
1 000 - 1 700
1 700 - 2 200
2 200 - 2 600
2 600 and above
Table 1
Number of lances
1
2
3
4
5
Select the lance model from Table 2 to match the known duct width.
Duct width in mm
Recommended lance model = 6
Step 4 - Select the system
Number of recommended lances required = 3
Table 2
Select the system that will handle the known capacity (Type 20 or Type 40) to obtain the required valve Kv. See overleaf and the example below:
Type 20
system
with
multiple
lances
Supply pressure
0.25 bar g
0.5 bar g
1.0 bar g
1.5 bar g
*2.0 barg
42
70
105
140
154
Lance model
1
1.5 to 12
Kv 7
Kv 5.8
Kv5
Kv 4
Kv 3
Kv 2
Kv 1
Steam
load
kg/h
* Recommended maximum inlet steam pressure to separator for quiet operation of the humidifier. For operating pressures above 2 bar g consult
Spirax Sarco.
It will be seen that the Type 20 system for multiple lances requires a Kv value of 5.8
Step 5 - Select the control valve and separator
Having selected the required valve Kv, the actual valve size and actuator can now be found from the chart headed 'Valve selection' on
TI-P795-03. Always select the next highest valve Kvs, to the Kv required.
Recommended control valve is a DN20 LE31 with screwed BSP connections.
Recommended actuator is an EL3502SE for 24 V operation VMD control signal.
Final product selection and specification from the above example:
1 x Spirax Sarco S.I. humidifier for 110 kg / h at 1.5 bar g; 1 x Type 20 separator with DN20 LE31 valve screwed BSP,
with EL3502SE actuator for 24 V operation VMD control signal, and 3 x Type 20 model 6 lances.
Local regulations may restrict the use of this product to below the conditions quoted.
In the interests of development and improvement of the product, we reserve the right to change the specification.
© Copyright 2004
