Glossary of Terms

Submicron particles suspended in air, gas or vapor. A fog, fume, or smoke.

Ratio of total mass or weight of the material divided by the volume of the material (includes void volume in the case of solids).

To unite small droplets of one liquid preparatory to its being separated from another liquid. Filter/coalescer cartridges coalesce small water droplets present in water contaminated fuel and certain oils into larger drops which are then separated by gravity.

Continuous Phase

The basic product flowing through a filter or filter/separator which continues on through a system after being subjected to solids and/or water removal.

See “Pressure Drop” below.

Discontinuous Phase

The phase dispersed in the continuous phase; water is a discontinuous phase to be separated from a hydrocarbon liquid or from air or gas.

The quantity of liquid which makes up one spherical mass; a liquid globule.

A small drop which may coalesce to form larger drops.

Stream of fluid at the outlet of a filter or filter/separator. Opposite of influent.

A dispersion of fine droplets in the continuous phase.

Carry-over of fibers from filter or separator media material into the effluent. Fiber migration is a qualitative part of total media migration.

The fluid which has passed through filtering media. Also referred to as effluent from filters.

Gravity Separation

Separation of immiscible phases resulting from a difference in specific gravity.

Water accepting or water wettable. Opposite of hydrophobic.

Water repelling. Lacking affinity for water. Opposite of hydrophilic.

Liquids which are mutually insoluble; opposite of miscible.

Stream of fluid at the inlet of a filter or filter/separator. Opposite of effluent.

Carry-over of fibers and particles from filter or separator media material into the effluent. Includes fiber migration, expressed as milligrams per liter.

Liquids which are mutually soluble. Opposite of immiscible.

The difference in pressure between two points, generally at the inlet and outlet of a filter or a filter/separator. Measured in pounds per square inch, inches of mercury, kilograms per square centimeter, kilopascals (kPa) or bars (1 bar = 14.5 psi). (Also commonly referred to as Delta P or differential pressure.)

Specific Gravity

The ratio of weight of a fluid to the weight of an equal volume of standard substance; i.e. water for solids and liquids, and air or hydrogen for gases.

Static Generation

Unbalanced or net electrical charge produced in a flowing hydrocarbon liquid.

Surface-active agents, which are also called detergents, emulsifiers, or wetting agents. Polar compounds. (Most surfactants in jet fuel can be removed by clay treatment.)

A filter/separator vessel containing coalescers, separators and 3rd stage monitor cartridges (e.g. CDF® cartridges)

A filter/separator containing two kinds or types of cartridges (coalescers and separators).

The time rate of motion or speed in a given direction.

A molecular property of fluids: the friction of molecular motion. A more viscous fluid has a higher pressure drop at a given rate of flow, as compared to a less viscous fluid.