A Career in Industrial Safety, Catastrophes……. What do we Learn from them?
by
Mr. Ishan Karna and Mr. Karanveer Singh Marwah,
(both authors are B.Tech. Chemical Engineering with specialization in Refining and Petrochemical)
INTRODUCTION
In recent years, the threat of chemical disasters has increased with greater interaction of harmful chemicals with humans. The threats of chemical disasters are more significant than natural disasters because the exact potential of these chemicals is still unknown. The experience of natural disasters has given us an idea of their nature, magnitude, and variety, in contrast, chemical threats are not understood well, for several reasons.
First, while hazardous materials are themselves not entirely new in our society, their widespread production and use, as well as their damage-producing potential, have increased dramatically only in the last few years, and this increase is not yet universally recognized.
Second, with hundreds of potentially dangerous substances present in or passing through our communities daily, and with thousands of potentially dangerous combinations possible, chemical threats display tremendous variety, compared with natural disaster threats.
Third, compared to most natural disaster agents, hazardous materials are unstable, complex, and capable of alteration.
Fourth, taking precautions against chemical mishaps necessitates sophisticated protective measures which in general are not well understood by non-specialists.
Lastly, industries harnessing chemical power to meet the demands of the people do not have enough money to make the use of those chemicals safe, thus we see a greater chance of chemical accidents due to human negligence and safety in developing nations.
The Indian Perspective
With hundreds of accidents every year, India is one of the chemical disaster hotspots with numerous casualties and long-term impact on the health of the people. Most of the accidents involve human error, and negligence. Broadly, Technical and Physical causes of accidents comprise 73%, Organizational causes are 23% and Unknown causes are 4%.
The detailed breakdown of causes landing into unsafe acts and unsafe conditions are Piping System: 17%, Management Procedures: 16%, Contaminations: 10%, Material Selection: 8%, Mass Transfer: 7%, Corrosion: 7%, Substandard Equipment: 5%, Heat Transfer: 5%, Flow Related: 4%, Knowledge Base: 4%, Fabrication: 4%, Storage/Handling: 4%, Unknown: 4%, Layout: 3% and Control Systems: 2%.
Following accidents have recently occurred, provide a chance to improve our systems and remind to maintain apt standards of safety even when a common chemical is involved.
Prevention of blasts like these is essential. Hazardous material like Ammonium Nitrate must be stored carefully, under supervision and in properly labelled containers. Fire extinguishing services must also be there to minimize the impact in case of a fire.
CASE BRIEF
Beirut Blast
On August 4th, 2020, a port in Beirut witnessed one of the largest explosions killing one hundred people and making another three hundred thousand homeless. The explosion’s shockwave blew out windows at Beirut International Airport’s passenger terminal, about 9km (5 miles) away from the port. The blast was also heard as far away as Cyprus, about 200km across the Mediterranean Sea, and seismologists at the United States Geological Survey said it was the equivalent of a 3.3-magnitude earthquake.
According to Lebanese officials, 2,750 metric tons of Ammonium Nitrate had been stored in a hangar at the city’s port. The stores had been there since September 2013 after the ship carrying the material was forced to make an unplanned stop in Beirut where it was then abandoned by its owners and crew. Before the explosion, a fire had started in the area, creating a plume of white smoke and small explosions. When the ammonium nitrate stores exploded, a white condensation cloud spread out in a sphere from the site, followed by a huge plume of red-orange smoke rising from the hanger.
Chemists identified that color was a signature of Nitrogen di-oxide, NO2 gas, produced from the incomplete decomposition of ammonium nitrate. When energy is applied to ammonium nitrate, like from a fire, the molecule is no longer stable. Because ammonium nitrate contains nitrogen in two different oxidation states, an exothermic reaction occurs between the two nitrogen species: the nitrate acts as an oxidizer, while the ammonium acts as a reducing agent. If the reaction is completely clean, the only products are dinitrogen, water, and a little oxygen, but side products like NO2 are common. Because all the products are gaseous, there is a sudden, significant increase in pressure that will then travel outwards at supersonic speeds, which is referred to as the detonation.
The blast not only destroyed homes of the people, but also destroyed the grain stock of Beirut with only one month of food left. The blast also took in grain silos with it making an irreparable impact on the lives of the people.
Assam Gas Blowout
The Assam Gas Blowout which killed three people along with large scale evacuations and damaged the Dibru-Saikhowa National Park. The incident happened on 27th May 2020 with a gas leak at well No: 5 (out of 22) in Oil India Limited’s Baghjan Oilfield in Tinsukia district, Assam, India. The Baghjan Oil field is located near the National Park in Assam, and is remarkably close to Mogri Motapung Beel, a natural wetland. The National Park is the only riverine wildlife globally and it is also connected to Namdapha National Park these regions are part of the Indo-Myanmar Biodiversity Hotspot.
Baghjan Well No. 5, from which the leak occurred, is located at nine hundred meters from the park and adjoins a buffer forested region surrounding the park. Earlier in the year, administration allowed all the oil the companies for conducting exploration work without compliance to legal requirement for environments clearance which had resulted in the protests.
After the gas leak, the well caught fire on 9th June and the blaze was enormous that it could be seen from 30 km away resulting in the evacuation of 4488 people.
The authorities tried to douse the fire but were unsuccessful and in the process two fire-fighters lost their lives.
Fire can be ignited due to three factors i.e., ignition temperature, fuel & Oxygen. So, at the burning well, firefighting authorities had two options, first is to make blast of antioxidants making the area around it with no oxygen for a time being resulting in extinguishing. Second was to wait for the oil in well to vanish that would mean the blazing could continue for years. A firefighting team from Singapore came on 27th August i.e., 110 days after blowout, the experts successfully diverted the gas to two control flare pits. This cut off the supply to the well head for the fire to die out, this was done by reducing the surface level well head pressure with basic idea of NO fuel NO fire! Relief officials needed to kill the 3.7 km deep well to prevent it creating problems afterwards. Sixty tons of snubbing unit were imported from Canada which arrived on 4th November, and it took 5 days to reach at site. This machinery injects artificial mud (comprises of cement and brine solution) at high pressure, and it took 4 days to complete fill the well. Finally, after 173 days of blowout the official were able to control the fire.
In investigation it was revealed that the official was replacing a damaged spool at well for that they removed the Blow out Preventer (BOP). During the process, the pressure increased, and the gas had a kick and the blowout occurred.
Vizag Gas Leak
On the 7th of May 2020, the country woke up to tragic news of a chemical gas leak in the town of Vizag in Andhra Pradesh. The event made us remember the dastardly crime of Bhopal Gas disaster. Though this gas leak was controlled, many people died, and many will live with lifelong illness. A total of twelve people were killed and around eight hundred hospitalized because of the gas leak.
The leak took place at the LG Polymers chemical plant in the R. R. Venkatapuram village on the outskirts of Vizag. The plant was re-opened on 7 May 2020 after the cross-country lockdown executed as a reaction to the COVID-19 pandemic. 2,000 metric tons (1,968 long tons; 2,205 short, huge loads) of styrene in tanks, left unattended. Styrene monomer must be put away between 20–22 °C (68–72 °F) on the grounds that higher temperatures bring about fast vaporization. It is accepted that a technical glitch in the industrial facility’s cooling framework permitted temperatures in the capacity tanks to surpass safe levels, making the styrene vaporize. Between 2:30 to 3:00 AM, when support action was in advancement, the gas spilled from the plant and spread to close by towns. The poisonous fumes spread over a radius of three Kilometers which resulted in hundreds of people rushing to hospitals for medical assistance, straining the already strained medical system due to the pandemic. The people suffered from breathing difficulties and other effects. People were even found lying unconscious on the ground as the result of the inhalation of the gas.
There were many reasons which shaped this disaster to happen, human negligence being the main. After a team of experts were consulted, the state government directed the South Korean Petrochemicals major to remove 13000 Metric Tonnes of the material out of the country. To minimize the effects, around 500kgs of 4-tert-butylcatechol (PTBC) was airlifted by the Government and sent to the factory. Further the company bought polymerization inhibitors and added into the tanks of styrene stored at LG Polymers to prevent further degradation and any future gas leaks.
Fukushima Daiichi Nuclear Disaster
The Fukushima Daiichi Nuclear disaster was a nuclear accident at the Fukushima Daiichi Nuclear Power Plant in Ōkuma, Fukushima Prefecture, Japan which occurred on 11th March 2011. The nuclear disaster was the most extreme one since Chernobyl disaster in 1986. The Fukushima Disaster was initially claimed to have been caused by terrible earthquake of magnitude of 9.0 followed by 14m high Tsunami waves. Later, it was found to be a manufactured disaster caused by the negligence.
This disaster led to the evacuation of 20 km area around the plant which estimated around 154,000 residents evacuated from the communities surrounding the plant due to the rising off-site levels of ambient ionizing radiation caused by airborne radioactive contamination from the damaged reactors. Substantial amounts of water contaminated with radioactive isotopes were released into the Pacific Ocean during and after the disaster.
Fukushima Nuclear Plant produced energy from the fission nuclear reaction. The plant had six units and when the earthquake occurred unit 4, 5 &6 were shut down due to schedule inspection, but the units 1, 2&3 were working. Immediately after the earthquake, working units 1, 2&3 had automatically shut down with AZ-5 button which introduces the control rods to stop the reaction. When the reactor stops operating, the radioactive decay of unstable isotopes in the fuel continues to generate heat (decay heat) for a time, and so requires continued cooling. This decay heat amounts to approximately 6.5% of the amount produced by fission at first, then decreases over several days before reaching shutdown levels. The cooling is achieved by pumping coolant and in the case of shutdown this is achieved by diesel generators.
When Tsunami waves flooded the plant, these generators of unit 1-5 failed which led to overheating. The switching stations that provided power from the three backup generators located higher on the hillside failed when the building that housed them flooded. AC power was lost to units 1–4. All DC power was lost on Units 1 and 2 due to flooding, while some DC power from batteries remained available on Unit 3. Only unit 6 pump was working it was also connected to unit 5 which had the capacity to pump the coolant in both units, so unit 5 &6 were in control. Further, batteries and mobile generators were dispatched to the site, but were delayed by poor road conditions. Unsuccessful attempts were made to connect portable generating equipment to power water pumps. The failure was attributed to flooding at the connection point in the Turbine Hall basement and the absence of suitable cables which led to meltdown of units 1, 2&3. The piping system of unit 3 & 4 was interlinked which resulted in the flow hydrogen to unit 4 making it meltdown. Also, the seismic force produced due to earthquake exceeded the limit of unit 2, 3, 5 which worsen the situation.
Investigation report states that response was flawed by poor communication and delays in releasing data on dangerous radiation leaks at the facility. The report said that the authorities neglected the earthquake and tsunami risks. The 40ft high tsunami waves were double the height of waves predicted by Tokyo Electric Power Company (TEPCO) official on analyzing worst case scenario. The erroneous assumption that plant cooling system would function after the Tsunami, worsened the disaster. TEPCO had not trained its official on how to respond to disaster, there were no independent decisions in response to the disaster especially when the diesel generators failed. TEPCO did not provide the dosimeters to all his official which could keep the check on the radiation leak. The report also stated that plant initial design was 30 ft higher than the seabed, but TEPCO reduced it to 10ft for the ease of transport. The miscommunication between TEPCO and government depicting a scene of harried officials incapable of making decisions to stem radiation leaks as the situation at the coastal plant worsened in the days and weeks following the disaster. The government ignored the advance computerized system for response of such disaster which could keep a continuous check on radiation and evacuation plans.
CONCLUSION
For reducing the risk of chemical accidents, we need to respond appropriately and institute robust data collection measures. It will require substantial reflection and coordination across countries and industries at international level to identify measures that can be applied in a broad range of countries with varying level of industrial activity, varied institutional arrangements and practices for governing industrial risk, and cultural and social differences. Check on chemical accident risks globally is likely to be achieved through a combination of data collection measures, with both government and industry making contributions. Data collection should be customized to reflect local circumstances and different expectations for countries with various levels of risk governance. Countries with more competence and experience would be expected to have more sophisticated data collection measures in place for assessing progress and with time other countries will expertise in risk reduction efforts, they can also begin to implement more advanced assessment strategies.
These accidents are often underestimated because of their low frequency. In some countries such incidents are never reported because of low public awareness, lack of government attention and geographical limitations of impacts. The developed countries that see industrial accidents as normal event and ignore the stem of the problem. The complexity of improving risk management is daunting for emerging economies. Systematic measurement of the accidents can help them priorities and target problematic areas.
In this regard, assessment of risks needs to cover all types of hazard sources viz fixed facilities, transport, pipelines, and offshore facilities as well as non-chemicals industries using dangerous substances which may require certain level of hazard control.
Strengthening data collection on past accidents should also be a priority. Data on past chemical incidents is fundamental to global and national assessment of chemical accident risk. However, these data are only a starting point for making a more robust assessment. By itself, aggregate accident data can hide significant gaps and challenges in risk reduction efforts associated with economic sectors and technological and social change. Moreover, the low frequency of severe chemical accidents means that incident data associated with any one country or industry, or even across several countries and sites, is not a reliable indicator of underlying risk, particularly in locations where a certain level of risk control has already been achieved.
The last decade has seen the emergence of new innovative ideas that can form basis for international recommendations for data collection and the development of implementation models. It is imperative to have an assessment of risk reduction performance so that adequate attention can be given to chemical accident risks. There is ample of motivation for all the stakeholders to engage in a process to develop more potent assessment measures for tracking chemical accident risk reduction efforts.
References
What Is Ammonium Nitrate, the Chemical That Exploded in Beirut?
- https://www.scientificamerican.com/article/how-could-the-beirut-explosion-happen-experts-explain/
- https://www.hindustantimes.com/world-news/beirut-blast-warnings-of-extreme-danger-ignored-by-
- lebanon-officials-about-stored-ammonium-nitrate/story-Sd2AA6YZmJ9PwbPZhUd6SK.html
- https://en.wikipedia.org/wiki/Visakhapatnam_gas_leak
- https://www.thehindu.com/news/cities/Visakhapatnam/visakhapatnam-gas-leak-how-negligence-and-
- violations-led-to-a-deadly-disaster/article31761949.ece
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- https://en.wikipedia.org/wiki/2020_Assam_gas_and_oil_leak
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- Power_Stations_of_Tokyo_Electric_Power_Company
- https://en.wikipedia.org/wiki/Fukushima_Daiichi_nuclear_disaster
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