Ship Operations - Wet Cargo (CHAPTER 1) Flashcards
(26 cards)
What is the simplest hydrocarbon?
Methane
What is it called when hydrocarbon molecules join together?
Chains
How many carbon molecules in a gas?
Less than 5
How many carbon molecules in a liquid?
Between 6 and 20
How many carbon molecules in a solid?
More than 20
What happens when evaporation equals condensation?
Saturation conditions exist
What is Saturated Vapour Pressure (SVP)?
The pressure exerted when saturation occurs
What happens when SVP equals atmospheric pressure?
The liquid will boil
What is the difference between volatile substances and non-volatile substances?
Volatile substances evaporate rapidly, non-volatile substances evaporate slowly
What affects evaporation?
Temperature
Surface Area
Liquid to vapour ratio
Turbulence
What is True Vapour Pressure (TVP)?
Highest pressure possible
What is Reid Vapour Pressure (RVP)?
A useful test for comparing the volatility of different products
What is Flashpoint?
Lowest temperature at which a substance gives off enough vapour to briefly ignite when an external source of ignition is applied
What flashpoint is volatile?
Below 60 degrees C
What flashpoint is non-volatile?
Above 60 degrees C
What is Auto Ignition Temperature (AIT)?
Temperature at which a substance will ignite without the application of an external ignition source
What is required for a fire to occur? And in what proportion?
Fuel (1-10%)
Oxygen (11-21%)
Heat (Sufficient amount to ignite a flammable mixture)
What is Lower Flammable Limit (LFL)?
Lowest concentration of hydrocarbon gas in air to support combustion
What is Upper Flammable Limit (UFL)?
Highest concentration of hydrocarbon gas in air to support combustion
What is the Flammable Range?
The range between LFL and UFL
What is the Flammable Zone?
The region within which combustion can take place
What is the region above the UFL called?
Too Rich
What is the region below the LFL called?
Too Lean
What is the region below 11% Oxygen by volume called?
Inert
