Corrosion Accidents in Refineries Preliminary findings from a study of recent accidents in OECD/EU countries

1. Corrosion Accidents in RefineriesPreliminary findings from a study of recent accidents in OECD/EU countries Maureen Heraty Wood European Commission Joint Research Centre Major Accident Hazards Bureau October 2010

2. Outline of Presentation • Background, aim and objectives of the study • Description of the study: approach, sources and underlying assumptions • Profile of (> 2000) OECD/EU accidents and comparison with historical data – impacts, scenarios, key factors, risk management issues • Study outputs and future direction observations about reporting and accident analysis activity

3. 1. Background: Why corrosion in refineries? • Aging of refineries is a topical issue. • Corrosion of energy exploration/production/distribution equipment in general has been a source of concern (and some major accidents) in recent years • Refineries compose a highly visible and complex sector within the major hazard spectrum • Most OECD/EU countries oversee at least one refinery, if not many. • OECD/EU countries without refineries all have petroleum storage depots • It is an important and challenging research topic • It provides a rich opportunity to test and apply various analytical techniques for assessing accident findings • It is a promising topic for future collaboration & discovery

4. How Significant are Corrosion Accidents in Refineries? • Corrosion was a factor in 21.5% (28/128) of all accidents in refineries reported to the MARS database. • Since 2000, corrosion accidents in OECD/EU refineries have cost at least €1.6 billion ($2.2 billion) in property damage. • The costs of a single accident can be extraordinarily high. • Since 1980, 3 accidents account for the majority of 60 deaths and 370 injuries arising from these events*. • An accident in Germany in 2006 estimated € 9.5 million in environmental damage • Sixteen OECD/EU accidents* since 2000 were very high consequence and resulted in shut down of entire production units/refineries for weeks/months *if BP Texas City (2005) is included

5. Aim of the Study • The purpose of the study is to extract specific information from reports and studies about causes and countermeasures associated with recent corrosion-related accidents in refineries that may be useful to OECD and EU government and industry in prioritising and implementing actions to prevent major accidents.

6. Objectives of the Study • The objectives of the study are as follows: • To create a detailed profile of scenarios and key factors associated with recent (> 2000) corrosion accidents in OECD/ EU refineries • To compare profiles and key factors of recent accidents to past (< 2000) accidents involving corrosion in refineries in order to: • identify recurring patterns and factors • identify potentially new patterns and factors • make recommendations from historic knowledge base to address recent accident scenarios • make recommendations on strategic implications of study findings

7. 2. Study Approach • The analysis focuses on 33 corrosion-related refinery accidents reported to OECD/EU governments in the last 10 years • Exceptions: one MHIDAS from Australia, several high impact accidents reported in the Marsh Risk Report • Corrosion accidents in petroleum storage depots were also included (4 accidents) • Findings of the analysis will be based on: • comparison with/recommendations from the accident report themselves • comparison with/recommendations from accidents in an extended database (including journal case studies, insurance reports, non-OECD/EU & pre-2000 accidents) • technical publications on specific corrosive phenomena associated with refineries • relevant information on refinery production, cost data, etc.

8. Sources of Accident Case Studies

9. Total Case Distribution by Year and Country

10. 3. Post-2000 Accident Profiles and Historical Comparison

11. 3a. ConsequencesRanking of Consequences - Pre- and Post-2000 • Level of impact was assessed preliminarily based on estimation of consequences in one of the 6 categories – deaths, injuries, material loss, production loss and public disruption • For human consequences, production loss and public disruption, the scale approximates the European gravity scale (condensed into 5 categories) • For material and environmental damage, level of impact was assessed using a logarithmic scale from Low to High for costs starting with < €10,000.

12. ConsequencesDominant Consequence Impacts Reported Pre-2000 vs. Post-2000 • Dominant impacts reported for all accidents are represented, including “low impact” accidents • An event could have more than one high consequence impact.

13. Selected Post-2000 Very High Consequence Accidents

14. 3b. Key Scenario ElementsPre- and Post-2000 Accidents by Type of Risk Factor*(N = 97)** *Excluding management/organisational issues **Categories are not mutually exclusive. An accident can be associated with more than one type of risk

15. Key Scenario ElementsUnit Origin of Corrosion AccidentPre- and Post-2000 23% 20% 24% 14% 15% 9% 11% 8% 15% 12% 5% 9% = potential trend 3% 6% 2% 3% 0% Other includes oil degasification unit, generator, solvent extraction unit, saturated gas unit, scrubbing tower, olefin manufacturing unit, sulphur recovery unit

16. Example of a Process Flowchart of a Refinery www.fullwiki.org Storage Unit

17. Key Scenario ElementsUnit Origin of Accidents* Involving Substance-Related Corrosion 21 accidents 18 accidents 14 accidents All OECD/EU (When reported) N = 59 6 accidents *An accident/unit can be associated with more than one substance. **Other substances include kerosene, LPG, nitrogen, phosphoric acid, coke

18. Key Scenario ElementsEquipment Type (from 59/97 reported) 6% 44% Other = various other piping internal to a process, e.g., “between cooling tower and reflux”, “on the naphtha stripper”, etc.

19. Key Scenario ElementsEquipment Components Involved in Corrosion Accidents – Pre- and Post-2000 ! = potential trend ! ! = no change? Other includes pressure vessels (2), baffles (drums), tank shell, wall contact Note: The numbers represent actual numbers not percentages

20. 3c. Top Risk Management Issues (Reported) – 1-10 Pre-2000 (N = 64) Post-2000 (N = 33)

21. Top Risk Management Issues (Reported) – 11-20 Pre-2000 (N = 64) Post-2000 (N = 33)

22. Summary of Findings • Corrosion accidents in OECD/EU refineries continue to occur at high cost to the economy with high potential for severe human and environmental consequences. • Despite numerous major accidents in the past, there is still a lack of attention in the following areas: • Known process risks are routinely ignored • Detection and mitigation mechanisms are often inadequate despite high risk potential for leaks/ruptures in certain units • Inspection schedules often ignore known risk factors associated with corrosion • Process changes are not recognised as new risks requiring a revision of the risk assessment • There appears to be a lack of knowledge concerning proper use of corrosion protection measures for equipment, compounded by economic factors

23. 4. Study Completion and Outputs • In the near future the current findings will be refined and some key issues will be further explored (particularly equipment and process risks) • In 2011, final drafts will be produced for • an EUR report summarising the findings, and also including background on corrosion phenomenon • An article for the Loss Prevention Bulletin focusing on a selection of case studies • Scientific journal article • Additional analysis may also look at: • Improving barrier analysis for existing refinery accident scenarios • Corrosion indicators • Others?

24. Future Direction of the JRC Accident Analysis Activity • Production of a report is expected every 6 months • Different types of reports may be produced to allow regular production within limited resources • Major reports will usually be presented as preliminary • Smaller narrowly focused reports that can be finalised in a 6-month period • An external review process will be piloted with the corrosion report • Currently we are considering using experts on an ad hoc basis, rather than establishing a specific review panel • The process will likely evolve as we gain experience • These plans assume adequate resources. 

25. Study Implications for Reporting Issues • Collectively, the existing OECD/EU databases are a rich source of technical knowledge and management info. • Short reports that are precise and focused are no less useful than large reports • The best examples are JST and ARIA • MARS has some excellent reports but inconsistent format • Precise figures for consequences are also helpful • This is a strength of both MARS and JST • Some countries (incl. OECD/EU) are not represented • Lack of resources, lack of awareness, or language? • Are there any sources for reported incidents in Canada, South America, Australia, Africa, Asia (other than Japan)?

26. Future Accident Analyses? - IExamples of Recently Reported Cases (> Summer 2009) • Contractor issues (3 events) – Example. During cleaning of a petrol tank an explosion occurred. The contractor who was cleaning inside the tank at the time died in the accident. His dead body could only be removed 3 hours after the explosion as the structure of the tank was ruined. • Collision of equipment. (3 events)Example. Explosion and fire of hazardous chemicals storage caused by the release of sodium chlorite from metal drums, hit by an erroneous operation of a forklift. The explosion triggered a domino effect involving other drums and bags containing hazardous chemical products present in the hangar and caused the collapse of the hangar due to the pressure wave. The collapse of the structure caused the death of the operator crushed by the debris. The pressure wave injured a second operator who was hospitalised and dismissed in the evening. The pressure wave damaged also the adjoining solids storage hangar, causing the collapse of part of the structure, and ignited some small fires due to spark projection.

27. Future Accident Analyses?- IIExamples of Recently Reported Cases (> Summer 2009) • Loading/Unloading (2 events) Example. While unloading a ship in a chemical product storage facility, 20 m3 (13.3 t corresponding to 6.65% of the Seveso threshold of 200 t) of trichloroethylene spilled into a retention basin filled with water. The accident was caused by connecting the unloading pipe to an unstopped line and poor coordination between operators on the ship, the unloading tank and the road-tankers used to clear the necessary storage volume. • Coal/tar/iron/steel production. (4 events)Example. Fire in a tar distillation plant with material damage of approx 15.000.000 EUR and 10 persons injured. Presently it is assumed that the failure of a flex-hose in the fluid seal system of a circulation pump caused the ignition of a primary fire followed by a deflagration. This may have caused the leakage of some product piping system component and a secondary fire. • .

28. Future Accident Analyses?- IIIExamples of Recently Reported Cases (> Summer 2009) • Electroplating (2 events) Example. Forming of nitrogen oxides in a electro-plating plant. Consequent to the event 49 persons had to be hospitalised for observation. Nitrous gases formed when nitric acid got in contact with metallic parts (zink-coated wired baskets) . Nitric acid 53% was involved with approx. 50 kg as primary product • Tank/vessel rupture. (4 events)Example. A vessel containing titanium tetrachloride ruptured and released its contents. An employee was standing beneath the vessel when this happened and suffered chemical burn injuries to his skin and lungs. He died in hospital on 18 March 2010, therefore this incident is reportable under Annex VI of the Seveso Directive. • Start-up after unplanned/emergency shutdown.(1 event) On 26 June, about 15h45, a violent storm led to the stop with a total blowoff of the installation for ammonia production. The thunderstorm caused a complete power failure as well on the high voltage as on the low tension grid. There was no automatic check of the complete circuit (valves, etc.) before starting the process. Two workers were injured in the explosion.