Re-assessment

During routine boiler water testing, the pH is recorded at 9.0. What is the likely risk in this situation?

• Scale formation increases significantly

• Risk of acidic corrosion and pitting

• Embrittlement of boiler steel

• Excessive foaming

You find dissolved oxygen levels above recommended limits in boiler water. The immediate treatment required is (a)   .

• Add sodium phosphate
• Add sodium sulfite
• Increase blowdown rate
• Add calcium hydroxide

A junior engineer records boiler water hardness at 70 PPM. What is the operational implication?

• High corrosion risk due to acidity

• Scale and sludge formation

• Increase in foaming tendency

• Reduced conductivity readings

Why is oil contamination in boiler water considered critical during operation?

• It causes pH to become highly alkaline

• It promotes foaming and overheating

• It increases dissolved oxygen concentration

• It increases hardness level

Match the following property parameters with their corresponding checks for a high-pressure boiler experiencing constant scaling despite treatment.

• Measure the ability of water to conduct electricity

• Conductivity

• Check for impurities in the fuel

• Alkalinity

• Determine the concentration of hydroxide ions

• pH level

• Assess the acidity or basicity of the water

• Oil content

If the total solids/conductivity reading exceeds the recommended limit, (a)   occurs.

• Oxygen corrosion increases
• Boiler plates become brittle
• Scaling and carryover occurs
• Dissolved oxygen removal efficiency

If phosphate concentration falls below 30 PPM in boiler water, what problem might arise?

• Corrosion from chloride ions

• Hardness salts remain unreacted causing scale

• Excess foaming due to oil contamination

• Alkalinity increases beyond safe limits

While bunkering fuel, the chief engineer decides to mix two different fuel oils in the same tank. What is the primary risk?

• Increased catalytic fines concentration

• Sulphur content infringement or compatibility issues

• Flash point increases above safe limit

• Pour point drops below usability temperature

The environmental impact of using heavy fuel oil with high sulphur content is that it (a)   .

• Increases flashpoint hazards
• Releases sulphur oxides causing aci
• Causes catalytic fines to damage in
• Reduces kinematic viscosity leading

If flashpoint of fuel oil supplied is recorded at 55°C, what is the action required onboard before usage?

• Heat the fuel to raise its flashpoint

• Reject the fuel as it does not meet SOLAS minimum flashpoint

• Mix with higher flashpoint fuel

• Increase purifiers’ throughput