(189c) Biomass Industry Explosion Case Study

This case study will review an explosion that occurred in a biomass processing facility. There were several pieces of equipment involved including a conditioner (which served as a dryer), a screw conveyor and a cyclone. Thankfully, there were no injuries or fatalities due to this incident. This event occurred at a global biomass company, resulting in damaged equipment with one piece needing to be completely replaced. Other equipment was able to be repaired and returned to service.

Material handled in the process had been observed to smolder on prior occasions, but the cause of these near miss incidents was not investigated or identified. The material was a potential combustible dust and there was also the possibility for flammable gas to be generated due to decomposition. Through material characterization, several hazards were identified. Combustible dust and calorimetry testing were employed to evaluate the thermal stability, reactivity and combustibility of the material. In addition, off-gases were evaluated to determine if flammable gas was generated. This case study will outline the test design strategy to obtain key process safety information, identify the multiple hazards based on the test results, review existing explosion safeguards and determine a postulated series of events that could have led to the incident. Lessons learned from the incident will be reviewed including recommended risk reduction strategies that could be used to prevent future events. One example is the importance of obtaining appropriate process safety information to facilitate data driven decisions to be made regarding safe operating conditions.