Process Safety in the Workplace: How One Site Failed
11.3.18
From reading the two articles linked in the bottom of this blog post I've gathered the following information concerning an explosion and subsequent fire at the Williams Olefins company Plant in Louisiana. This accident included the deaths of two employees. Twelve years of safety management oversights lead to the reboiler (a type of heat exchanger) to have no measure to prevent or protect from overpressure. This then lead to the explosion. The U.S. Chemical Safety Board wrote a 74 page report on how officials on sight treated safety procedures as something to worry about if something went wrong, and not as something to use to prevent these types of accidents.
This plant produced ethylene and propylene, two high volume commodity chemicals, though the accident closed operations for 18 months while repairs were made. Besides the human lives, the cost of cleanup & repair, the accident cost the company $13.6 million in compension to four of the other victims who were injured. In a quote from the latter article below, "several plant officials and its parent company were negligent and knew with substantia certainty that the deadly fire could occur," and in an effort to save money/effort they lost so much more. The bottom line in many of these companies similar is quite literally, money. Nothing is more priceless than employee and the community's safety.
In the case of the reboiler the plant actually had two reboilers side by side, which used to operate in tandem. They function by using heated water to vaporize propane which can then be broken down into other hydrocarbon substituents. These boilers now operated one at a time, so on was on and running while the other was being cleaned and then idled ready to use. While one was idling, liquid propane entered, possibly by a valve being opened accidentally, and then heated up inside the reboiler. The propane then expanded and escaped the boiler, causing sparks upon exit and then exploding into a fireball. Many officials in charge of upkeep of safety guidlines knowingly checked boxes that were not supposed to be automatically checked without physical tests to verify. The operations code was also noted to be "confusing" for workers to follow.
This just emphasizes the importance of process safety to me, and how each day one has to go in and review safety features as if it's the first time. Getting complicit in the workplace can lead to injuries and death down the road, for you and for others.