Question 1

What is the purpose of a fuel oil purifier (centrifuge) in the fuel system, and what happens if fuel is supplied to the engine without adequate purification?

Accepted Answer

The purifier removes water and solid contaminants (e.g. catalyst fines, sediment, rust) from the fuel before it reaches the engine; if fuel bypasses adequate purification, water can cause combustion problems and corrosion, while abrasive solid particles (particularly catalyst fines from certain fuel grades) can cause rapid wear to fuel injection equipment, piston rings, and liners Catalyst fines (residue from the refining process, present in some residual fuel grades) are extremely hard, abrasive particles that, if not removed, cause accelerated wear of fuel pumps, injectors, and engine components — purifier performance (correct throughput rate, temperature, and bowl condition) is therefore directly linked to engine reliability and maintenance costs, not just a routine housekeeping task. Water in fuel can also cause incomplete combustion and, in severe cases, damage to injection equipment from the resulting pressure spikes.

Question 2

You're draining a thermal oil system that was running normally a short time ago. Before opening the drain point, what should you confirm?

Accepted Answer

That the system has cooled and depressurised, and you are positioned clear of the drain point's discharge path On the dredger MV Amazone, two crew members draining a thermal oil system after months of contamination were sprayed with hot oil, suffering severe burns. The investigation found company procedures lacked clear instructions for safe drainage — confirming the system has cooled and depressurised, and standing clear of the discharge path, are essential before opening any drain point on a hot oil system.

Question 3

A thermal oil system has been contaminated and needs draining for cleaning. The written procedure tells you to open the drain valve but doesn't specify a cooling-down period or PPE. What should you do?

Accepted Answer

Treat the gap as a hazard in its own right: apply a suitable cooling/depressurising period and full PPE before proceeding, and raise the procedure gap with the Chief Engineer The FEBIMA investigation into the MV Amazone incident found that although the crew followed company procedures, those procedures lacked clear instructions for safely draining a thermal oil system. A procedure that's silent on cooling time and PPE for a hazardous task is a gap to be closed before the job starts — not a green light to skip those precautions.