WorksheetsFuel Oil ICHEM-02-TAP
Total questions: 20
Worksheet time: 10mins
At what standard temperature is fuel oil density typically measured?
0°C
15°C
50°C
100°C
Which property is defined as the resistance of fuel to flow?
Density
Pour Point
Viscosity
Flash Point
According to SOLAS, what is the minimum flash point required for marine fuels?
40°C
50°C
60°C
70°C
What is the term for the lowest temperature at which fuel remains fluid?
Cloud Point
Fire Point
Pour Point
Flash Point
What is the maximum global sulfur content limit for fuel oil established by IMO 2020?
0.10%
0.50%
1.00%
3.50%
Which property is a measure of the ignition quality of distillate fuels?
Carbon Residue
Acid Number
Cetane Index
Ash Content
In what unit is fuel oil viscosity commonly expressed?
kg/m³
ppm
mg KOH/g
centistokes (cSt)
Which physical property helps distinguish between fuel grades like HFO, MDO, and MGO?
Water Content
Density
Ash Content
Acid Number
Why is fuel density critical for the operation of onboard purifiers?
It dictates the necessary heating temperature
It determines the fuel separation efficiency
It indicates the presence of sulfur
It prevents corrosion in exhaust valves
At what temperature is the kinematic viscosity of residual fuels (HFO) usually measured?
40°C
50°C
100°C
15°C
What is the acceptable limit for water content in fuel oil by volume?
<0.1%
<0.5%
<1.0%
<5.0%
What is a consequence of high Conradson Carbon Residue (CCR) in fuel?
Reduced fuel density
Improved ignition quality
Excessive soot and deposit formation
Lower sulfur emissions
What is the maximum sulfur content permitted for fuels used within Emission Control Areas (ECAs)?
0.50%
0.25%
0.10%
0.05%
What does a high Total Acid Number (TAN) indicate?
Low sulfur content
High energy content
Potential fuel degradation and corrosion risk
Better fuel separation in purifiers
What is the typical Hydrogen to Carbon (H/C) ratio for residual fuels?
~1.0
~1.8
~2.0
~3.5
How does a higher Hydrogen to Carbon (H/C) ratio affect the combustion process?
It increases the viscosity
It increases the pour point
It allows the fuel to burn cleaner with less soot
It makes the fuel harder to ignite
Which metal contaminant reacts with sulfur to cause high-temperature corrosion in exhaust valves?
Vanadium
Sodium
Silicon
Aluminum
What is the typical value range for the Cetane Index in marine diesel engines?
15–25
30–40
40–55
60–75
What is the primary operational risk of high ash content in fuel oil?
It increases the fuel's flash point
It causes fouling in exhaust systems and turbochargers
It makes the fuel too thick to pump
It decreases the sulfur oxides produced
Which property determines the temperature at which wax crystals begin to form in the fuel?
Flash Point
Pour Point
Cloud Point
Fire Point
