Heat from Oil Fire Melted Metal on Thermal Oil Heater

Location: Peace River

Regulated industry sector: Boilers, PV & refrigeration – Boiler and pressure vessel system

Incident overview

The S-tube heat exchanger of a wood waste thermal heater leaked several hundred litres of thermal oil at a lumber mill. The oil caught fire and damaged the S-tube heat exchanger, convection ducting, and the flue gas dust separator. Upon investigation, it was found that soot had accumulated in the S-tube heat exchanger and around it, forming blockages and resulting in incremental heat damage over time. Finally, an induced draft broke through the soot and ignited a secondary fire during the time of the incident.