Definitions in waterfiltration

Brownse beweging
Random movement of small particles in a fluid

Bubblepoint
Pore size measured at the pressure which is required for a air bubble to get through.

Effective output
The ability of a filter to remove particles, expressed in a percentage. There is no uniform rule for effective output, no rule for which effective output value is right or wrong. Effective output can be calculated with the following formula: Effective output = (Cin – Cout)/Cin

Filtermedia
The porous material, usually replaceable , which filters a fluid.

Filtrate
The fluid after a filtration.

Filtration
Mechanical separation of a solid fase or semi-solid fase from a fluid.

Micro Filtratie
Separation of particles with a size of 0.1 till 2 mm.

Micron (mm)
1*10-6 meter (0,00039 inch).

Nonwoven
Any material made without weaving or knitting.

Pore size
The biggest of average size of holes in a porous material expressed in mm.

Separation
The separation of a phase from another in an admixture.

Ultra Filtration
Separation from particles with a size of 0,001 till 0,1mm.

Vanderwaalsforces
The weak molecule-to-molecule forces which cause a small particle to adhere to a surface.

Pollution
Everything what is in a wrong place.

Active carbon
Porous active carbon is used for the removing of taste, smell, chlorine and some organic compounds out of water.

Bacteriostat
Substance which submerges bacterial growth and metabolism but does not kill the cel.

Cake
The accumulation of solid particles in the medium, the surface of the filter.

Cartridge filter
A filter, which filters with an range of 0.1 micron till 100 micron and usually with a diameter of 51 tillt 102 mm and a length of 152 tot 1524 mm.

Cloth
A type of woven filtermedium, made from natural or synthetical sources, like yarn.

Coagulant
Chemicaal toegevoegd aan water en afvalwater in de waterzuivering om tot de formatie van vlokken te komen die worden geadsorbeerd, ingesloten of op andere wijze samen gebracht en gedefineerd als colloïden.

Colloid
A substance of realy small particles with a diamter between the 0,001 and the 0,1 micron solved in a fluid or in a compressed gass. Colloid only can be removed by reversed osmosis, distillatie and ultrafiltration.

Conductibility
The ability of a substance to conduct electric power.

Resistance
The ability of a substance to stop an electric power.

Filtermedium
The permeable material which separates particles from a fluid.

Filtrate
A fluid which passes the filtermedium.

Flux
In crossflow filtration, the unit membrane througput, expressed in volume per time-unit per surface.

Fouling
At crossflow filtration the reduction of flux is caused by an accumulation of particles on the surface of the membrane.

Hardness
The concentration of calcium- en magnesiumsalts in water.

Micron
A metric unit, 10^ -6 meter, 10^ 4 centimeter. The symbol that is used for is mm.

Nanofiltration
A crossfiltrationmembrane which separates particles with a weight range of 250 till 1000 micron, selected salts and most of the organic compounds.

Permeable
Able to let particles through.

Pore
An opening in a membrane or filtermatrix.

Porous
The ability of some solid substances to let fluids through regarding an open structure.

Resin
Special manufactured polymer; application in ionexchangers to remove salts.

Septum
A membrane.

Backwash
Reversed flow through a filtersystem which is commenly used for the cleaning of mechanisms in sandfiltration.

Overview filtration-subjects.