- Process Equipment
- Process Vessels
The company investigation revealed that the incident arose because insufficient water was added to the batch. This resulted in a rapid increase in temperature and evolution of hydrogen gas following the addition of aluminum powder in the last seconds of the mix. Despite the presence of a functioning level-control valve on the mixer, the hydrogen gas was ignited when the operator opened the hatch. The most likely source of ignition was the faulty lamp. The operator was acting in accordance with his training and following the company's written safety procedures.
The company took a number of measures to prevent a reoccurrence of this incident, including:
provision of intrinsically safe lamps
introduction of daily checks of the vent valve
minor modification to LEV and increased venting throughout the mixing process
lab testing by the aluminum supplier to evaluate system safety with regard to hydrogen generation for all reaction conditions and quantities of aluminum added
reprogramming/development of the software to improve both the safety of the operation and operator understanding of warning alarms.