15 Aug 2018

How plants can avoid critical failures and be prepared

Emergency power supply during a refinery turnaround
 

No one could have predicted the devastation Hurricane Harvey would cause when the tropical storm hit America last year. Unprecedented amounts of rain and howling winds destroyed houses, businesses, and towns across the southern states but, at a plant in Crosby, Texas, the storm left something more dangerous in its wake.

This particular plant produces specialty chemicals. During the hurricane, faults to its electrical system and torrential flooding meant some of its stock caught fire and led to a series of explosions that affected the surrounding county for miles in every direction. 

Six feet of water took over the plant, causing a runaway reaction of the organic peroxides that were made on-site. As a result, people within a 1.5 mile radius were asked to evacuate immediately afterwards. 

The flooding disrupted the power at the plant, causing the refrigerator to go down and disaster to strike. The chemicals produced at the plant needed to be kept at a cool temperature, so continued refrigeration was absolutely vital. But, when the power went down and the backup generators failed, it was impossible to keep the chemicals in a safe state. 

On top of the explosions, two wastewater tanks overflowed which released over 23,000 pounds of contaminants. Despite its rural location, the toxins were carried by the floods into nearby homes, spreading heavy metals, dioxins, and semi-volatile organic compounds throughout the local area. 

Before the storm hit, a 12-person ride out crew were stationed at the plant to manage any damage that might occur. At that time, employees were predicting just minor floods rather than the huge swathes of water that engulfed the plant. 

But it wasn’t just this plant that drastically underestimated the power of Hurricane Harvey. During the storm, six other oil refineries in the area were forced to operate at reduced rates, while the excess flooding knocked over two storage tanks spilling more than 30,000 gallons of crude oil. Elsewhere, Exxon and Shell refineries were forced to close as they released pollutants amongst the torrential rains, and the Colonial Pipeline had to shut down all operations. 

The question on most people’s lips after the disaster was: could this have been prevented? 

Nearby residents and county officials of Crosby were quick to criticize the plant for not preparing well enough - after all, the site does sit in a floodplain. In response, the county filed a lawsuit against the plant after groundwater and the surrounding land was severely contaminated. 

“The facility was not prepared for such heavy rainfall and flooding,” said the Chemical Safety Board, going on to state that coming up with key ways to combat the effects of a disaster like Harvey was a top priority for the plant. 

If the plant had been better prepared, the loss of refrigeration could have been avoided and, therefore, eliminated the chance of any explosions taking place.

 

How the Plant Could Have Been Better Prepared

Perhaps the biggest fault of plant staff was the assumption that flooding would be minor. They based their predictions on the last fifty years of experience without taking into account the fact that nature can be incredibly unpredictable.

With better planning, they could have quickly moved chemicals off site to a safer location and put a backup refrigeration system in place. 

One of our customers, a synthetic crude plant, was set to carry out an overhaul of their coker unit when the main air blower unexpectedly went down. This disrupted the schedule which would have led to serious losses for the plant. 

We quickly provided a series of air compressors alongside 56 pieces of electrical distribution equipment to get the overhaul plans back on track. We also provided a senior engineer and project manager to oversee activities 24 hours a day throughout the process. 

As a result, our temporary system bought the plant 18 more days of smooth operation until the main air blower could be reinstated. This saved the customer almost C$70 million and meant they could continue to keep their output at a consistent level. 

No plant is immune to critical failures, but having a backup plan in place for when disaster strikes can help avoid dangerous situations like the one at this particular plant. If the plant had planned ahead and considered a temporary solution for the failed refrigerator, they might not have faced a hefty lawsuit and a huge loss in profits.