SX PLANTS

EW PLANTS

LEACHING

HYDROMET

COALESCERS

CLASS OF COMBUSTIBLE AND FLAMMABLE LIQUIDS

Combustible Liquid: A liquid having a flash point at or above 100 °F (38 °C).

Class II:     Flash point > 100 °F (38 °C) and flash point < 140 °F (60 °C).

Class IIIA: Flash point > 140 °F (60 °C) and flash point < 200 °F (93 °C).

Class IRB: Flash point > 200 °F (93 °C).

Note: When a combustible liquid is heated for use in a solvent extraction circuit to within 30 °F (17 °C) of its flash point, it should be handled in accordance with the requirements for the next lower class of liquids.

Flammable Liquid: A liquid having a flash point below 100 °F (38 °C) and having a vapour pressure of 40 psia at 100 °F (38 °C).

Class 1A: Flash point < 73 °F (23 °C) and boiling point < 100 °F (38 °C).

Class 1B: Flash point < 73 °F (23 °C) and boiling point > 100 °F (38 °C).

Class 1C: Flash point < 100 °F (38 °C) and flash point > 73 °F (23 °C).

Flash Point: The lowest temperature a which a combustible or flammable liquid will give off enough vapours to form an ignitable mixture with air.

Lower Flammable Limit: The percentage of vapour in the air above which a fire can not occur because there is not enough fuel (the mixture is too lean).

Upper Flammable Limit: The percentage of vapour in the air where there is not enough air for a fire to occur (the mixture is too rich).

Vapour Density: The weight of a combustible or flammable vapour compared to air (air = 1). Vapours with higher densities than air tend to be more hazardous because they can flow along the floor and collect in low spots.

Requirements for Combustible Liquids: Electrical wiring and components in solvent extraction plants with combustible liquids (class II or class IIIA) should be suitable for general purpose locations.

Requirements for Flammable Liquids: Electrical wiring and components in solvent extraction plants with flammable liquids (1A, 1B, or 1C)  should be suitable for class I, division 2 hazardous locations.

For more details regarding: Electrical Requirements for SX Plants. 

Note: The organic phase in most solvent extraction plants that use kerosene as a diluent have a flash point above 140 °F (60 °C) and are handled in accordance with the requirements for class II or class IIIA combustible liquids.

Diluents used in Solvent Extraction Plants: (Combustible Liquids)

Extractants used in Solvent Extraction Plants: (Combustible Liquids)

Extractants used in Solvent Extraction Plants: (Flammable Liquids)