1. AL-KHODARI INDUSTRIAL
TRADING & SERVICES
Dealing with corrosion

2. Company headlines
Know-how in processes and
installations for powders and liquids,
Consulting and implementing
installations with optimal R.O.I.,
Reliable process solutions with
minimal complexity,
Innovative and active supporting in
process issues.

3. Services
Process engineering
Engineering
• Mechanical
• Electrical
Production
Process control
Mechanical installation
Electrical installation
Maintenance & service

4. Experience & know-how
Milk of lime
• Storage & dosing of (quick) lime
• Mixing, storage & dosing of milk of lime
Slurry handling
• Coal, sand, sulfur, magnesium oxide, etc.
Paint & compounding
Storage, dosing and handling of hard-to-handle
materials
Glue preparation
• Preparing, cooking & dosing of PVA or starch based glue
Liquid handling
• Dosing skids
Storage & handling corrosive materials

6. References
Akzo Nobel
Akzo Salt Chemistry
Carmeuse
Chemetall
Degussa
Interbrew Nederland
Koninklijke Marine – Royal Dutch Navy
Nestlé Nederland
PPG - SigmaKalon Coatings
Rockwool Lapinus B.V.
Sabic Melaf
SHELL Ned. Chemie
Smurfit Kappa Packaging
Fokker Nederland – Parts for JSF and Apache 9 helicopter
Waterschap Zuiveringschap Limburg – waste water treatment
Waterschap Zuiveringschap Brabant – waste water treatment

8. Designing & engineering on
material behavior
Corrosion
Erosion
Viscosity
Chemistry
Hazard

9. Corrosion
General Corrosion
Pitting Corrosion
Crevice Corrosion
Stress Corrosion Cracking
Galvanic Corrosion
Microbiologically Influenced Corrosion
Sulphide Stress Corrosion Cracking
Intergranular Corrosion

10. Pitting corrosion
Defect in passive Corrosion
layer allows metal products
to dissolve Concentrated
iron chloride
Cathodic solution
Passive
oxide
layer
Anodic
Electrochemical process

11. Pitting corrosion
Inhibitors:
Chloride (catalyst)
High temperatures
Acidic conditions, low pH, such as CO2, H2S
Damaged oxide layer (chemically inhibited)

12. Pitting corrosion

13. Crevice corrosion
Similar to pitting corrosion
Occurring:
Under gaskets,
Sharp re-entrant corners
Incomplete weld penetration
Overlapping surfaces

14. Pipe weldings
crevice
crevice
crevice
Welding Sufficient Sufficient Insufficient Sufficient
pre- weld weld weld weld
treatment penetration penetration penetration penetration

15. Crevice corrosion

16. Pitting & crevice resistance
High grades of chromium, molybdenum and
nitrogen
Pitting Resistance Equivalent number (PRE):
PRE = %Cr + 3.3 x %Mo + 16 x %N

17. Pitting & Crevice resistance
316L
316L

18. Chloride content water

19. Chloride content water
Temperature 88-100 °F 31-38 °C
Flow rate
75% recovery Chloride [ppm]
[GPM]
Feed Flow 1667 1400
Brine Flow 417 5595
Permeate Flow 1250 0,5
Flow rate
68% recovery Chloride [ppm]
[GPM]
Feed Flow 1838 1400
Brine Flow 588 4375
Permeate Flow 1250 0,5

20. Chloride content water
FEED 68% 75%
316L
316L

21. Stress Corrosion Cracking
Inhibitors:
Stress and corrosive environment
Stainless steel
Elevated temperature
Only applicable to austenitic steel
(201, 301, 303, 304, 305, 316, 321, 347, 631)

22. Stress Corrosion Cracking

23. Galvanic corrosion
Contact of dissimilar
metals in electrically
conductive liquid
Welds, containing
ferrites and due to
different structure
Contact metal with
corrosion products
 Contact corrosion
Contact corrosion
accelerates pitting &
crevice corrosion

24. Galvanic corrosion

25. Microbiologically Influenced
Corrosion (MIC)

26. Microbiologically Influenced
Corrosion (MIC)
Inhibitors:
Stagnant areas of flow
Micro-organisms
Bio-films of (other) micro-organisms
Surface roughness
Nutrients
Oxygen!

27. Microbiologically Influenced
Corrosion (MIC)
Types of organisms:
Algae (Probable in saltwater with O2)
Fungi (Improbable)
Bacteria (Aerobic & Anaerobic)

28. Microbiologically Influenced
Corrosion (MIC)
Tubercles formation
facilitating
pitting/crevice
Bio-film creating corrosion
isolated environment
Corrosion underneath biofilm

29. Microbiologically Influenced
Corrosion (MIC)
Prevention / resistance:
Maintaining cleanliness
Monitoring quality of water
Smooth surfaces
Avoiding stagnant areas
Stainless steels with
molybdenum > 6% are
virtually resistant to MIC

30. PRE = %Cr + 3.3 x %Mo + 16 x %N

31. Sequence of corrosion
 Crevice corrosion at gaskets, crevice /
galvanic corrosion at welds.
 Contact corrosion due to corrosion products.
 Algae settle on corrosion induced roughness
 Bacteria settling at algae/roughness
 Formation bio-films and degrading agents
 Acceleration of corrosion processes up to
1000 times of ‘normal’ process

32. Unusual and excessive degree of
corrosion can occur unpredictably,
due to specific local conditions

33. Chloride content water
FEED 68% 75%
316L
316L

34. Pictures RO skid
Penetrated weld
Contact/galvanic
corrosion
Crevice corrosion

35. Pictures RO skid
Pitting corrosion
Facilitated by
stagnant water

36. Pictures RO skid
Contact corrosion
Corrosion by
polluted welding
material

37. Pictures RO skid
Contact corrosion
by polluted welds

38. Pictures RO skid
Contact corrosion
Consequential
MIT on rough
surface
Density MIT
related to lines
Corrosion
processes related
to stagnant water

39. Conclusions
Basic types corrosion: pitting & crevice corrosion
Primary corrosion propagated by contact
corrosion and Microbiological Influenced
Corrosion
Stagnant areas over a longer period of time are
facilitating & accelerating corrosion enormously
Stainless steel 316L in RO skid will corrode
Worst case circumstances were available
Serious risk is unpredictability of corrosion
reaction velocity; several cases of sudden
unusual degree of corrosion are known

40. AL-KHODARI INDUSTRIAL
TRADING & SERVICES
Specialized in process installations for
handling dry and liquid materials

41. Proposed actions
Survey of similar installations at Aramco:
• Compare differences in materials / set-up
• Examine water compositions
• Compare biological analyses
• Evaluate state of corrosion to age
Conclude either whether risk level incurred
in common practice is acceptable or
common practice is to be re-defined