1. Clean and Pure steam in the Biopharm industry
Kieran O’Keeffe
European Business Manager
High Purity Products
Spirax Sarco Ltd.

2. Typical Steam Circuit Steam Space Heating System Tank Process Vessel
Boiler
Feed Pump
Feed Tank
Make-up Water
H/Exchanger
Condensate
Steam
Process Vessel
Space
Heating
System

3. Driving standards Filtered Clean Pure 3A’s
UK Heat preserved foods guide
FDA (Materials)
Clean
EN285
HTM2031 / 2010
FDA (Material)
Pure
EN285
HTM2031 / 2010
ASME BPE
FDA (Material)
FDA cGMP
USP
ISPE

4. Pure Steam Generation Pure Steam Generator cGMP, ISPE, BPE designed
3 phase moisture separation
External compact evaporator column
Generation Capacity from 50 kg/6T/hr
Units can be Electric or Steam/Steam

5. Requirements of the system
“It is essential that that the steam is delivered to the point of use is of the correct quality and purity for the process”
Three areas of design should be considered;
Production
Distribution
Point of use

6. Quality and purity Quality V’s Purity Dryness
Dryness of >95% is essential
Excess moisture can cause;
- Damp loads in porous materials
- Uneven temperature distribution in non-porous loads
- Uncontrolled chemical composition of steam
Will have the effect of not sterilising correctly

7. Quality and purity Quality V’s Purity Steam Dryness Testing procedure
D= (T1-T0)(4.18Mw+0.24) _ 4.18(Ts-T1)
LMc L
T0 = intial temp of water in flask
T1 = final temp of water in flask
Ts = average temp of water and condensate in flask
Mw = Initial mass of water in flask
Mc = mass of condensate collected (kg)
L = latent heat of dry sat steam at temp Ts (kJ kg-1)

8. Quality and purity Quality V’s Purity Superheat
Superheat should not exceed 25 deg C (77 deg F)
Problems incurred with Superheat include
- Poor heat penetration resulting in Failure to sterilise
- Scorching of textiles and paper
- rapid deterioration of rubber

9. Quality and purity Quality V’s Purity
Steam Superheat Testing procedure
Superheat content = temperature of steam in the expansion tube – temperature of boiling water at local atmospheric pressure

10. Quality and purity Quality V’s Purity Non-condensable gases (NCG)
Gases which can not be liquefied by compression under the range of temperature / pressure experience in the sterilising process.
NCG’s should not exceed 3.5% by volume
High NCG content can cause Bowie and Dick test failure

11. Quality and purity Quality V’s Purity
Non-condensable Gas Testing procedure
Fraction of NCG = vol of gas collected in the burette / vol of water collected in the measuring cylinder.

12. Specific Volume Vs Pressure Saturated Steam
0.2
0.4
0.6
0.8 1
1.2
1.4
1.6
1.8 2 3 4 5 6 7 8 9 10 11 12 13 14
Pressure (bar g)
Specific Volume
(m3/kg)

13. Steam Properties
Steam Tables

14. Distribute at High Pressure
Smaller bore steam mains needed and therefore less heat (energy) loss due to the smaller surface area.
Lower capital cost of steam mains, both materials such as pipes, support work and labour.
Lower capital cost of insulation (lagging).
Dryer steam at the point of usage because of the drying effect of pressure reduction taking place.

15. Pipe Distribution Greater Cost Greater Heat Loss
Greater Volume of Condensate Formed
Lower Pressure to Steam Users
Not Enough Volume of Steam
Water Hammer and Erosion

16. How is pipe sized ?
On the basis of:
Steam Velocity
Pressure Drop

17. Steam Pipe Sizing Chart (kg/h)
Pipe Sizing Chart Velocity
Steam Pipe Sizing Chart (kg/h)

18. Pipeline Capacity and Pressure Drop
Fluid Flow P2 L

19. Steam Line Drainage

20. Clean and Pure Steam
Distribution
Condensate removal
Adequate Support

21. Clean and Pure Steam Distribution Condensate removal
Steam traps should drain vertically downwards to avoid condensate hold up

22. Ineffective, and Proper Drain Points
Steam Flow
Condensate
Correct
Incorrect
Cross Section
Pocket
Steam Trap Set
25/30m
Steam Flow
Cross Section
Steam Trap Set

23. Clean and Pure Steam
Distribution
Steam take-off

24. Steam Line Reducers
Condensate
Correct
Incorrect
Steam

25. Steam Take - off
Shut Off Valve
Trap Set
Main
Drop Leg

26. Recommended Support Spacing

27. Expansion Chart for Mild Steel Pipe
Temperature difference oC/metre
Length of pipe (mm)
Expansion of pipe (mm)
Temperature of Saturated Steam

28. Warm up load/running load per 50m of pipe``
Ambient temperature 20  C, insulation efficiency 80%
Lower figures represent running loads

29. Questions