1. Designing an Internal Corrosion Program NACE Eastern Area Conference Roy D. Fultineer Jr.

2. Introduction Plans and Procedures Plans and Procedures Training Training Know the system Know the system When do we get involved When do we get involved Understand Corrosion Mechanisms Understand Corrosion Mechanisms Identify the right monitoring locations Identify the right monitoring locations Monitor and Trend data Monitor and Trend data Possible Mitigation Possible Mitigation Follow-up Follow-up

3. Plans and Procedures Internal Corrosion Plans Internal Corrosion Plans – Generic Potential Treats – Acid Gases, Bacteria, Erosion, etc. Potential Treats – Acid Gases, Bacteria, Erosion, etc. Types of monitoring Types of monitoring – Gas samples – Liquid samples – Coupons Requirements for internal corrosion monitoring Requirements for internal corrosion monitoring Parameters to monitor and trend Parameters to monitor and trend

4. Plans and Procedures Internal Corrosion Plans Internal Corrosion Plans – Generic Basic Decision Criteria Basic Decision Criteria – If indications are found, what is the next step.

5. Plans and Procedures Internal Corrosion Plans Internal Corrosion Plans – Specific Location of facility Location of facility Specific location of monitoring locations Specific location of monitoring locations Specific timing of monitoring Specific timing of monitoring Specific water control methods Specific water control methods – Pigging – Drips – Dehydration Schedule of these control methods Schedule of these control methods What action has been taken? What action has been taken?

6. Plans and Procedures Internal Corrosion Plans Internal Corrosion Plans – Specific What action is planned? What action is planned? How will action be evaluated? How will action be evaluated?

7. Plans and Procedures Procedures Procedures – Procedures go into specific action of how to conduct sampling and monitoring – Important aspect of internal corrosion plan – Procedures go hand-in–hand with training

8. Training Properly trained personnel is critical to the success of any internal corrosion program Properly trained personnel is critical to the success of any internal corrosion program – In house training – On the job training – NACE and other professional organizations Collecting accurate data is critical Collecting accurate data is critical The better the data, the better the decisions The better the data, the better the decisions

9. When do we get involved Internal corrosion should be considered in the initial design phase of any project Internal corrosion should be considered in the initial design phase of any project Things to consider: Things to consider: – Water content and water removal – Elevation profile – Inlets and outlets to the system – Gas Quality – Flow regimes

10. Know your system Operation Factors Operation Factors – Direction of flow – Flow rates – Flow regime – Pressures – Product – Upsets – Elevation Profile

11. Elevation Profile

12. Understand Corrosion Mechanisms Causes – – Water – – CO2 Influenced – – H2S Influenced – – MIC – – O2 – – Velocity/Flow Related

13. Understand Corrosion Mechanisms Water – Necessary for internal corrosion – Temperature Reaction rates double for every 10 degree Celsius rise Reaction rates double for every 10 degree Celsius rise – pH Less then 5 can result in increased corrosion Less then 5 can result in increased corrosion – Carbonates Acts as a acid buffer Acts as a acid buffer

14. Understand Corrosion Mechanisms CO2 Corrosion – Carbon Dioxide + water = Carbonic Acid – Carbonic Acid + iron = iron carbonate + hydrogen – Carbon dioxide is in the gas – Carbonic acid creates corrosion – Generally mild corrosion except when with other corrodents

15. Understand Corrosion Mechanisms H2S Corrosion – Hydrogen Sulfide + iron + water = – Iron Sulfide + water + hydrogen – From sour gas operations or from SRB’s (MIC) – Corrosion pitting occurs where FeS forms on the metal surface and creates a local corrosion cell

16. Understand Corrosion Mechanisms MIC – Acid Producers - APB’s – Sulfate Reducing Bacteria - SRB’s – Controlled with a clean system and bacteriacides/biocides

17. Understand Corrosion Mechanisms Oxygen – Oxygen + iron + water = Iron oxide + water – Oxygen creates an oxidizing effect and with other corrodents = accelerated corrosion – Oxygen concentration cells create corrosion due to oxygen depletion areas

18. Understand Corrosion Mechanisms Velocity/Flow related attacks – High surface fluid or particle velocities – Erosion High Energy with or without particles High Energy with or without particles Removes metal Removes metal Leaves smooth surface Leaves smooth surface – Erosion Corrosion Erosion removes protective film or scale Erosion removes protective film or scale Exposes metal surface to environment Exposes metal surface to environment

19. Pick the right monitoring locations Representative of system Representative of system Right location Right location – Know what your looking for and put monitoring devices in right location. – Top of the line versus bottom of line corrosion Right device Right device – Pick the monitoring device that is designed for the application

20. Monitor and trend data Collect the data you need and compare it to all other data Collect the data you need and compare it to all other data Be careful not to add to much weight to any one data set Be careful not to add to much weight to any one data set Determine if action is required Determine if action is required

21. Possible Mitigation Methods Do nothing Do nothing – Sometimes the best answer is to continue to monitor and study – More information will lead to better decisions – More technical or sophisticated analysis may be appropriate – Chemicals can actually make the situation worse

22. Possible Mitigation Methods Liquid removal Liquid removal – Drip Blowing Drip should be monitored and blown on frequencies that ensure no free liquids Drip should be monitored and blown on frequencies that ensure no free liquids Used to monitor for corrosion parameters Used to monitor for corrosion parameters – Pigging Ran on frequencies that ensure no free liquids Ran on frequencies that ensure no free liquids Thought should be given to the type of pigs used Thought should be given to the type of pigs used Speed of pigging can influence Speed of pigging can influence

23. Possible Mitigation Methods Dehydration Dehydration – – Removal of water through dehydration can greatly reduces possibility of internal corrosion – – High initial cost and added O&M cost – – Does not necessarily remove the need for chemical

24. Possible Mitigation Methods Control Inlet Product Quality Control Inlet Product Quality – Monitor product quality entering system – Have control to shut in suppliers

25. Possible Mitigation Methods Chemical Treating Chemical Treating – Batch – Slug – Continuous – Squeeze

26. Possible Mitigation Methods Design Design – One of the most effective means of control Use of proper materials Use of proper materials Size pipeline properly (oversized = liquid hold-up) Size pipeline properly (oversized = liquid hold-up) Modeling and/or flow regime will dictate location and/or need for drips, pigging, etc. Modeling and/or flow regime will dictate location and/or need for drips, pigging, etc. Material selection can be key Material selection can be key – Steel is not always the best solution – Example: Fiberglass piping in acid gas environment

27. Follow-up (Did it Work?) Coupons Coupons Liquid Sampling Liquid Sampling Residuals Monitoring Residuals Monitoring In Line Inspection (ILI) In Line Inspection (ILI) Gas Monitoring Gas Monitoring

28. Coupons Weight Loss Weight Loss – Compare previous rates to new rates – Compare pretreated versus post-treatment – CID – Copper Ion Displacement – monitoring chemical distribution

29. Liquid Sampling Monitor effects on water chemistry Monitor effects on water chemistry – pH (increasing or decreasing) Increase – Scaling Increase – Scaling Decrease – Corrosion Decrease – Corrosion – Metals (increasing decreasing) Mn/Fe ratio Mn/Fe ratio Trending Trending – Bacteria levels

30. Residual Monitoring Are chemicals getting where you need them Are chemicals getting where you need them Are the residuals adequate Are the residuals adequate If not, If not, – Adjust existing facilities – Add new injection points – Change application (continuous to pigging)

31. ILI Inspection Need base line Need base line Follow-ups Follow-ups – Monitor corrosion growth – Monitor for new corrosion.

32. Gas Monitoring Monitor Quality Monitor Quality – CO 2 – H 2 S – Water – O 2 Monitor for changes Monitor for changes

33. Questions?