Solution Provided | Hazardous Area Review of Alumina Refinery Digestion Area
Discipline | Process, Mechanical and Safety Engineering
Carnac - Project Delivery Services Pty Ltd (Carnac) was engaged to undertake an independent review of an incident that occurred in an Alumina Refinery where non-condensable gas leaking from a valve on condensate line was ignited due to hot-works being performed in the area.
The intent of this review was to determine the causes of the incident, identify it there were any underlying issues, and conduct a Hazardous Area Review to quantify the hazards associated with the contained Non-Condensable Gases (NCG) in the system. It was found that the main component of the NCG was Hydrogen, which has an extremely large flammability band.
Carnac identified multiple issues with regards to NCG safety in the area such as:
- The presence of ignition sources;
- Inadequate valve and pipe specifications;
- Dangerous isolation and purging procedures;
- Ventilation issues; and
- The lack of operational procedure for NCG system valve settings which can result in NCG accumulation in various vessels.
Recommendations were made based on priority, including a list of immediate recommendations to deal with the problems that posed the highest safety risks.
