Do you have emergency procedures for polymerisation reactions?

On January 31, 2006, a runaway reaction occurred at XXXX, while employees were making a  product. The polymerization reaction included toluene, cyclohexane, n-butyl acrylate, and benzoyl peroxide. According to the employer's records, there were 2,689 pounds of the solvent blend and 1,923 pounds of N-Butyl Acrylate in a Pfaudler reactor (M-1). Two 55-gallon drums and one 330-gallon IBC tote were positioned in front of reactor M-1. The containers held a solvent blend of toluene, cyclohexane, and benzoyl peroxide. At the time of the incident, the contents of one of the drums and a portion of a second drum had been transferred to the M-1 reactor. Employee #1 walked away from the reactor,
intending to turn a valve on the M-5 reactor to begin a nitrogen purge and move the contents of M-5 to M-1. While walking down a stair to perform this task, Employee #1 heard a loud, high-pitched sound. He immediately went back up and observed the Teflon 18 in. envelope gasket from M-1 hanging down from the manway and vapors coming through the opening. Other employees began to hear the sound. After Employee #1 observed the vapors being emitted, he walked outside and met other employees outside the production door, on the Northwest side of the building. Employee #2 was operating a forklift inside the drumming area when he heard the sound. He left the area and met with Employee #3 and Employee #4. They walked up to the Northwest side of the building. Employee #5 instructed Employee #3 to go get the Plant Manager. Employee #5 then donned a full-face respirator and entered the building to turn on the chill water to the reactor.
After a few seconds, Employee #5 returned after failing to obtain a good seal on the respirator and smelling vapors. Employee #1 then donned the respirator and went inside the building. Employee #3 and Employee #6 walked up and joined the other employees outside the production door. When Employee #1 exited the building, an explosion occurred. Twelve employees and two bystanders sustained various injuries. Five of the employees were hospitalized with various injuries, and one died later of burns.

Source: OSHA.gov

Storage of flammable and toxic chemicals - think about this

Continuing my previous post regarding effects of explosions, when you have large storages of flammable /toxic chemicals and are expanding your storage capacity, take into account if some thing can happen in your neighboring plant that can have fragments hitting your tanks. Here is an incident from osha.gov:

On May 27, 1994, Employees #1 through #3 were working at the XXX Chemical Plant in Belpre, OH. A catastrophic failure of a 15,000 gallon polymer reactor vessel was initiated by a runaway chemical reaction involving an abnormally high amount of 1,3-butadiene during the production of a polymer. The reactor failure and ensuing fire resulted in the complete destruction of the polymerization unit. Missile fragments from the failed reactor vessel damaged adjacent units in the plant. One fragment punctured a styrene storage tank approximately 600 ft away. This subsequently resulted in the burning of five styrene storage tanks containing approximately 3.5 million gallons of flammable products. Employees #1 through #3 were killed in the explosion

Explosions can have effects on neighbouring plants

Due you consider the effects of explosions from nearby plants that can affect you? Shrapnel from explosions can be thrown a large distance. In one case an urea plant reactor top flange and attached head from vessel were thrown about 385 feet (117.4 meters)  after it failed due to environmental stress cracking. Read the report in this link

Another incident (courtesy of osha.gov) is given below: 

On May 1, 1991, at the IMC Fertilizer, Inc., (IMCF)/Angus Chemical Company plant located in Sterlington, LA, a fire occurred in the area of a waste gas vent compressor (RJ-291) in the nitroparaffins (NP) plant. A few moments after the fire started, a series of explosions destroyed a large section of the NP plant, sending shrapnel north and east of the plant. Large debris weighing up to 150 pounds was hurled almost a mile away. Employees #1 through #8 of IMCF were killed and 42 were injured. In addition, approximately 70 residents of the town were injured and numerous businesses and residences were severely damaged.

Be careful when you deal with automated systems

With many valves being able to be operated from control room and also automated, this raises a hazard when carrying out maintenance. These automated valves should not open suddenly when maintenance work is going on. Do you have clear procedures to correctly Lock Out Tag Out and Try out such systems?

Read this incident:

At 9:00 a.m. on May 23, 2023, Employee #1 and Employee #2, both maintenance workers for a petroleum refinery were troubleshooting an automated valve in the "Prime G Unit". Flammable gasoline/hydrocarbons in the piping and flange portion of the automated valve were released causing an explosion and fire. Employee #1 sustained 3rd degree burns to over 83% of his body and was hospitalized. Employee #2 sustained 3rd degree burns to over 93% of his body and died on May 26, 2023. 

Source OSHA.gov

Catastrophic Explosion in CO2 Removal Unit of an Ammonia Plant

Good case study for those operating ammonia plants 

 https://www.researchgate.net/figure/The-view-of-the-incident-position-32-inch-semi-lean-amine-pipe-to-absorption-tower_fig3_315832742

Two employees are killed in explosion

 At 6:45 p.m. on September 20, 2022, the south area units of the refinery were experiencing process upset conditions, including lifting pressure safety valves and loss of pump arounds on the crude tower. Due to an incident earlier in the day, the NT/Sat gas unit and Coker gas plant were not in normal operating conditions. During work to troubleshoot and provide stability to the process units, the opening of a flow control valve to the absorber stripper tower in the Coker gas plant resulted in naphtha to flow downstream, eventually filling the TIU fuel gas mix drum with naphtha. This led to liquid in the refinery fuel gas system, which initiated the shutting down of some operating units. During outside employee response to the high liquid level in the TIU fuel gas mix drum, naphtha was released into the atmosphere, forming a flammable vapor cloud at ground level and in the oily water sewer at the refinery. At approximately 6:47 pm, the vapor cloud ignited at/near the TIU fuel gas mix drum, possibly due to nearby fired heaters, in the crude unit. Both of the outside employees who responded to the high liquid levels were severely burned in the explosion. Both of the employees died due to their burn injuries in the early morning of September 21, 2022. 

Source:OSHA.gov

Employee suffers burns and fracture in explosion at refinery

 An employee was working for a contractor that supported gas and oil operations. On or before December 21, 2021, a leak was found on a flange for a bypass line on the Hydro Desulfurization Unit (HDU-1) at refinery operated by an international oil company. The leak was detected because the leak had auto ignited. The refinery owner's fire team had been called out to put the fire out. After the fire was out, steam lances were continuously directed on the flange due to the potential of another flash fire from the leaking heated naphtha. The refinery's owner hired two contract companies to repair the leaking flange using a method called hot bolting. In this method, one bolt at a time was removed and replaced so that workers could install a wire wrap and seal the leak. The replacement bolts were longer and had injection collars. Workers would do the wire wrap and inject the bolts with a sealant to stop the leak. At 1:00 a.m. on December 23, 2021, an employee was working for the contracting firm that would remove and replace the bolts, while the other contractor assisted. As the employee was waiting for the other contractor, an explosion occurred during the repair. The employee suffered second-degree burns. In addition, he suffered a fractured femur when he was struck by a flying object from the explosion. He was hospitalized. Another worker there was not hospitalized. The employee's supervisors knew that the flange had auto ignited the day before they were called to come and fix the leak. The supervisors did not, though, ensure that employees had upgraded their personal protective equipment (PPE) to reduce the risk of serious injuries should a flash fire reoccur. They did not evaluate the hazards and select and require the use of appropriate PPE using their knowledge of the operating conditions, nor did they use refinery owner's safe work practice requirement of using upgraded PPE when work activity is going to be done in areas with potential flash fire. 

Source:OSHA.gov