Filled with art deco taverns, unique Flemish art, towering gothic cathedrals and quant guild homes, Belgium’s capital city Brussels, also home to the European Union’s headquarters, is a hub of political and business activity, making it the perfect place for an organisation at the top of the gases industry, setting the tone of safety, to hold its annual event.
A long-standing fixture on the industrial gas calendar month of January, the European Industrial Gases Association (EIGA) kicked off its annual Winter Seminar today – which this year celebrates its 25th event, gasworld can exclusively reveal.
Under the theme of Lessons Learned in Production and Filling Plants, gasworld has joined more than 200 delegates from 30 countries to explore why even in one of the safest industries, accidents still happen and the lessons that can be learned from them.
Returning once again to the stunningly beautiful Le Plaza Hotel Theatre, EIGA’s President Ivo Bols officially opened the conference and welcomed delegates to Brussels.
He highlighted the great number of participants in attendance – 202 to be exact – which he said demonstrated the appeal of the programme.
“Safety is not an intellectual exercise to keep us in work. It is a matter of life and death. It is the sum of our contributions to safety management that determines whether the people we work with live or die. That’s a quote from Sir Brian Appleton,” Bols said.
“Why are we hosting this seminar? To address lessons learned from significant industry incidents and share this information; to provide insight to safeguards from today’s design and operation; to address technical, organisational and human factors; and to look to the future and help maintain the corporate and industry memories.”
Over the course of the two-day event, seven sessions will be centred around three objectives:
- To remind new generation employees of some significant accidents that happened in the industry, as well as the lessons learned from these accidents
- Share some good practices, as well as innovative initiatives as a response to these lessons learned
- Reflect on the future challenges but also opportunities that new technologies bring in this new way of working.
Severe accidents in our industry
The first speaker of the day was Martin Snape, Director of EHS and Quality for Europe at Air Products, and EIGA Safety Advisory Council (SAC) Chair, who presented a summary of the accidents that have occurred in the industrial gas sector in the past 12 months.
He told delegates that in 2019, seven fatalities linked to the industry in Europe were reported – six reported by EIGA members and one reported by a non-EIGA member, with five of these fatalities as a consequence of four road traffic accidents.
The other two fatalities occurred in gas company sites – a contractor exposed to ammonia during preparations for tank periodic testing and an employee was hit by a flexible hose which ruptured.
“Road transport continues to be the activity by which we in the gas industry and others interfacing with our equipment are most at risk of serious industry or fatality,” Snape said.
“The recent focus on telematic, cameras and coaching can only help reduce such events.”
When looking at lost time injuries and recordable work injuries from the past 15 years, Snape said it was clear to see the industry has stopped improving and is on a plateau.
“There are no significant improvements overall. Larger companies’ performance is at best on a plateau although showing signs of improvement in the last 12 months,” he said.
“Improvement in the smaller companies’ performance as reported in 2018 has not been sustained over the last 12 months.”
“Road operations continue to be our highest risk activity and human factors continue to dominate.”
Next, Pierre Petit, Technical Director of the Engineering Technical Commission, the organisation responsible for writing and updating Air Liquide Group Design Safety Rules, discussed the safe operation of ASU reboilers.
“At Air Liquide, we have had two major incidents related to ASU reboilers. One related to a downflow reboiler in Malaysia in 1997 and one related to a bath-type reboiler in China in 1997,” Petit told delegates.
“As a result of forest fires, there was a large content of flammable contaiminents in the air, passing Front End Purification (FEP).”
“Accumulation of these contaminants in the liquid oxygen passages of the reboiler resulting in the ignition of those contaminants and propagation of combustion to large fractions of aluminium material (Brazed Alumininum Heat Exchanger).”
“This created a violent energy release and the explosive rupture of the distillation column and cold box causing damages to the surroundings caused by the blast.”
“After analysis of vaporised liquid oxygen from the reboilers, it was found there was no hydrocarbon analysis in plant 1 and in plant 2, a gas chromatograph analysing vaporised LOX samples from the reboiler was unable to detect contaminants from smog.”
Petit then reminded delegates of the EIGA safety rules for bath-type and downflow reboilers which included:
- Design the plant taking into account air contaminants, regularly assess air contaminants
- Operate pre-purification as per procedure, monitor CO2 removal
- Operate deconcentration systems (cryo fillers, purge) as per procedure
- Monitor flammable and plugging contaminants in LOX (maximum content as per reboiler type)
- Manage transient phases
- Perform periodic deriming as per procedure
- Ensure no contamination during maintenance
Rebecca Halls, Air Products’ Process Technology Manager, then covered the failure of a flat bottom tank that happened in the US 41 years ago – an incident which she said is the most serious incident in Air Products’ history.
On 31st January 1978 at around 8am, a 1,000 tonne flat-bottom liquid nitrogen tank overpressured.
“This tank was designed in 1967, hazard review had been performed and the tank design met all codes and industry practices at the date of manufacture,” Halls explained.
The excess pressure put upward force on the inner tank dome, the anchor straps failed and the inner vessel ejected from the outer jacket and fell to grade.”
“Coupled with this, the liquid nitrogen outer jacket roof detached and fell and broke the adjacent liquid oxygen flat bottom tank liquid line upstream of the shutoff valve.”
“This resulted in an uncontrolled 800 tonne liquid oxygen spill, five contractors exposed to high oxygen concentration levels and the authorities stopped air, land and river traffic for seven hours.”
“This incident was not only company altering but industry altering. It prompted new tank design changes and existing tank fleet retrofits to greatly improve flat bottom tank safety.”
Hazardous events related to oxygen deficiency was presented next by Dr. Nikos Larass, Linde’s Process Safety Manager in the Global SHEQ Department.
Air contains 20.9% of oxygen, which is needed to sustain life. If oxygen levels drop to 18-11%, Larass said there would be a reduction of physical and intellectual performance without the sufferer being aware.
A further drop in oxygen to between 11% and 8% would result in the possibility of fainting within minutes without prior warning.
Oxygen levels of 8-6% would see fainting occur after a short time with resuscitation possible if carried out immediately.
With oxygen levels of 6-0%, fainting would happen almost immediately, with brain damage occurring even if rescued.
“There are no warning signs of oxygen deficiency. Lack of oxygen is a silent killer, but a major cause of industrial fatalities,” Larass said.
He highlighted two case studies where oxygen deficiency occurred – the de-icing of a main trunking box in a liquid nitrogen tank and the inspection of a turbine box inside a new ASU – and detailed best practices.
Incidents related to CO2, oxygen and cold embrittlement
After a coffee break, Aleksandra Jastrzębska, Messer Group’s Quality, Health, Safety and Environment Manager, kicked off session two with Carbon Dioxide – Not a Simple Asphyxiant.
“This is a gas which is widely used, especially in the food industry, but are we really aware of its hazards?” she asked delegates.
Jastrzębska told delegates that an incident took place at Messer Polska on 3rd May 2008 that triggered Messer’s focus on C02.
“3rd May is a public holiday in Poland and so there were no staff present on this day only two security guards.
“The accident occurred in a building where dry ice was produced and involved a CO2 storage tank.
“After investigating a hissing noise coming from the valve of a tank resulting from the power being switched off days earlier, including unfortunately the power to the CO2 indicator, one of the security guards died after exposure to high CO2 concentration,” she said.
What did Messer learn from this incident? The company:
- Established a preventative action plan for all Messer Polska plants where CO2 is present
- Issued a leaflet relate to CO2 hazards to all subsidiaries
- Held a safety day dedicated to CO2 hazards in all Messer Group subsidiaries around the world
- Presented the incident to EIGA
Concluding, Jastrzębska said, “Carbon dioxide asphyxiation and intoxication hazards are still underestimated.”
“We should consider the risk of intoxication for each workplace or application where carbon dioxide is used.”
“Employees should be provided with information on the intoxication hazards of carbon dioxide and educate employees on this topic and on preventive measures.”
Returning to the stage for the second time today, Air Liquide’s Pierre Petit. He reminded delegates of the cold embrittlement fracture phenomenon and blast effect consequences, as well as presented some old and recent incidents and the lessons learned from them.
Frédérique Cortial, Linde’s SHE Manager in Region Europe South, focused on Incidents Involving Liquid Oxygen Pumps.
Her presentation focused on three incidents:
- The complete destruction of a liquid oxygen tanker in Columbia
- The full loss of containment and serious damage to a filling plant in France
- A small fire on an ASU area but with a potentially severe impact in Thailand
“Liquid oxygen pump ignitions are important contributors of major fires in oxygen facilities,” he told delegates.
“It is important to remember to shutoff valves for tankers, shutoff valves between liquid oxygen pumps and tanks, have the right set up for alarms and test the efficiency of the instrumental loop, use compatible materials, apply maintenance procedures and train your people.”
In a last minute change to the agenda, it was over to Air Products’ Mike Cawthra, replacing Kulwant Birdi, to complete session two with Oxygen Compressor Failures.
He gave a brief history of fires/failures on this compressor to delegates, which included:
- 2002 fire – No certain cause established. On the balance of probability failure attributed to riveted impellers coming loose and causing excessive friction and fire – however this was not conclusive.
- 2004 fire – Cause established. On a routine shutdown both check valves (same design) at discharge failed to close, thereby letting high pressure gaseous oxygen back into the compressor and subsequently into the oily bearing chambers through the common process and oil seal gas system (subsequently changed).
- 2013 overspeed event – it was known that the main inlet control valve was compromised. However, on a routine shutdown to fix the control system, the Quick Control Valve (QCV) failed to close. Train overspeed occurred.
- 2017 near miss – After the 2013 overspeed failure, the compressor was rebuilt with rotors which had old style impellers on which the cover was riveted. Shutdown was taken to replace the riveted rotors with newly purchased welded cover impellers. During this routine shutdown, damage was found to Stage 8 seal. It is clear continuous running would have led to the seal becoming completely loose, which would have resulted in a major fire.
Cawthra then detailed lessons learned from the 2017 near miss:
- All rail fits are prone to fretting to some extent as there is usually micro movement
- Take careful note of rail fit dimensions during shutdowns, in particular axial clearance
- Review flow path around each rail and establish whether it could be more prone to fretting
- Review material of mating parts.
Fire and perlite release
Francisco Saavedra, Messer Ibérica de Gases’ Manager of Filling Plants, began session three by discussing oxygen fires in filling plants.
He highlighted 64% of the 450 accidents in EIGA’s SAC database occurred in filling plants, resulting in 10 fatalities. Between 2006 and 2014, he said Messer reported 19 oxygen burnouts, including two fatalities.
He told delegates about an incident that happened in a filling plant in Spain, which resulted in Messer launching an oxygen safety campaign.
Linde’s Christain Weikinger then discussed two cases where an oxygen promoted fire occurred and the lessons learned from them.
“The objective of my presentation is to create awareness of ignition mechanisms and consequential damages resulting from a metal fire,” he said.
“The mechanisms are theoretically well known, but the combination of different effects, harmless looking, can lead to an incident.”
One incident he explained was when a safety valve backfired in a liquid oxygen backup system, resulting in a fire.
“The backup test made the safety valve lift and leak. It caught fire and a violent energy release took place,” he said.
“The metal fire caused the breach of containment and was extinguished by depressurisation.”
He said key takeaways from this incident included:
- Pressure tests lifted pressure safety vales
- Particles moved into the seat area of the pressure safety valves which then leaked
- Repair efforts were not successful until the plug and seat were lapped in
- Lapping grease was left in the system after repair
- The rapid pressurisation by opening the downstream valve caused a kindling chain with adiabatic compression as an initial root cause.
Rudy Goossens, SHEQ Manager of Messer Belgium and Messer BV, then shared his experiences and learnings from an incident that occurred in one of Messer’s acetylene plants in the Netherlands.
“A fire occurred during the process of carbide transfilling from the container,” Goosseens said.
“Because the operator was standing close to the container, he suffered burns. Parts of the generator and container were also damanged.”
First findings revealed during the transfilling of carbide from the container to the carbide lock, the piece of carbide got stuck and blocked the lock valve.
When the container was lifted, acetylene came out, causing an explosive atmosphere. The operator tried to remove the stacked piece of carbide that got stuck, resulting in the metal rod sparking and igniting.
“Lessons learned and company actions as a result of this incident included supervision, highlighting the importance of risk assessments, incident sharing with EIGA and the authorities and Messer launched an acetylene campaign to the whole Messer Group,” he said.
Rounding out the session, Michele Castelli, responsible for the Engineering and New Investments Department of SOL Group, gave analysis of two incidents that occurred in the past decade during perlite removal from an ASU cold box.
According to Castelli, perlite is used extensively to insulate cryogenic equipment, particularly in ASU cold boxes.
It is a non-toxic and non-flammable product but, due to its nature (very lightweight material) and the large quantities involved, it requires the use of special care and operation during handling.
“The main risk,” Castelli said, “is the uncontrolled perlite release that could have potential impact for personal injury and plant shutdown time.”
“Located in the interspace between cryogenic equipment and cold box enclosures, perlite is constantly purged with dry nitrogen to prevent entrance of atmospheric air.”
“Measurements are used to ensure that there is always positive pressure at all points within enclosures.”
“Changes in purge gas pressure or flow can indicate a blockage or leak within the enclosures.”
Castelli then detailed two case studies, the contributing causes and lessons learned from them.
The final four presentations of day one covered cylinder rupture by stress corrosion, cylinder burst by material gas incompatibility, incidents with forklifts and ignition of a capacitor bank in an ASU Electrical Substation.
Day two of EIGA’s Winter Session 2020 continues here in Brussels tomorrow, covering good practices, initiatives to go further and future challenges and opportunities.
A full review of the event will be published in the upcoming March edition of gasworld Global magazine.