Oil Properties Flashcards
LEL, UEL (aka HEL) - and what is the range between LEL and UEL
Lower Explosive Limit, Upper Explosive limit, between this it is flammable, below LEL it is too lean, above UEL it is too rich.
Boiling point of Methane
-162 C
Reid Vapour Test what is it
Lab test in which liquid is heated to 37.8 C and the vapour pressure is measured
Reid Vapour Test what is its purpose
Allows comparison of vapour pressures of different liquids
A closed cup test it used to determine?
The flash point of a liquid
The division between volatile and non-volatile liquids is a flashpoint value of which temperature?
60 C
What is the Saturated Vapour Pressure
The Pressure of the tank when the rate of condensation matches the rate of evaporation and thus the pressure is at a constant
In a Reid vapour test the vapour to liquid ratio is
4:1
At atmospheric pressure the boiling point of normal Butane is
-0.5 C
Gas Evolution
Process where a gas is produced, i.e. evaporation
Hydrocarbons with 6 – 20 carbon atoms exist at normal atmospheric temperature and pressure as:
Liquid
Impurities and particulate content of crude oil allow what to happen?
Faster static Charge Dissipation
In a Reid vapour test the temperature of the liquid is
37.8°C
Threshold Limit Value (TLV) is a time weighted average concentration you may be exposed to based on a
8 hour day and 40 hour week
Evaporation occurs when
Molecules leave the vapour and go into the liquid
Petroleum vapour concentration of 100% LEL will rapidly cause symptoms of drunkenness, unconsciousness and death. 100% LEL is equivalent to
1.0% vol
Boiling vs Evaporation
Evaporation is slower and only occurs at the surface
Closed cup test what is it
Test done in lab to work out the flash point
Knowing the saturated vapour pressure of a liquid allows you to predict
The boiling temperature of the liquid
flammable range diagram the minimum Oxygen content to support combustion is
11% oxygen
The flammable range of petroleum vapours in air is
1 – 10% Vol
Saturated vapour pressure occurs when?
The rate of condensation is equal to the rate of evaporation
The main hazard of petroleum cargoes is considered to be
Flammability
