Hydrogen was found to be leaking from a vent line during cryogenic loading operations. The leak was attributed to a cracked weld on a hydrogen vent line that consisted of (1) double wall aluminum piping and (2) slotted spacers between the inner and outer line to provide a hydrogen gas blanket for insulation. The weld that failed was repaired using a "clamshell" over the area of the failed weld in order to support continued operations. A portion of the failed weld was removed for analysis prior to the repair. After operations, the clamshell repair was excised from the non-vacuum-jacketed double wall piping to allow further analysis of the failed weld. It was later replaced with a new half shell piping section.
In early afternoon, a northbound tractor-semitrailer with horizontally mounted tubes filled with compressed hydrogen at approximately 2400 psi (166 bar) was struck by a northbound pickup truck that veered into the semitrailer's right rear axle. According to witnesses, the tractor-semitrailer then went out of control and left the roadway, coming to rest approximately 300 feet (91 meters) from the point of impact. As a result of rotational torque and impact, the end of one tube was sheared off at the bulkhead and left the tube bundle. During the process, some of the tubes, valves, piping, and fittings at the rear of the semitrailer were damaged and released hydrogen. The hydrogen ignited and burned the rear of the semitrailer. In the meantime, the pickup truck had also run off the view more
A hydrogen leak at the flange of a 6-inch synthesis turbocharger valve in an ammonia production plant ignited and exploded. Hydrogen detectors and the fire alarm alerted the control room, which immediately shut down the plant, and the fire was then extinguished rapidly. There were no injuries caused by the accident, since the operator heard a wheezing sound and was able to run away just before the explosion occurred. The leaking gas was composed of 70% hydrogen at a flow rate of 15,000 cubic meters per hour. Property damages in the turbocharger included electrical cabling, melted siding, and heavily damaged pipes. The ammonia plant was shut down for more than a month.Five days before the incident, a problem with the CO2 absorber column led operators to open the vent downstream of the view more