Problem
|
Process
|
How it Works
|
Equipment Used
|
|
Turbidity - cloudy water that will clear if left to set for a few minutes.
|
Filtration
|
Mechanically traps particles between pores of media.
|
Filter tank and media with automatic backwashing head. Media will
vary depending on application.
|
| Turbidity - cloudy water that will
not clear if left to set for a few minutes. |
Ultra-filtration
(UF) or Flocculation |
Flocculation - Chemicals are added that will grow large particles that will settle out and then can
be mechanically removed by filtration
UF - A pump forces water through a membrane leaving the turbitity behind to be washed down
the drain. |
Flocullation - solution
feed pumps, static mixers, and filters
UF - Membrane, strorage and repressurization
pump. |
|
Low pH - Blue-green staining-pin hole leaks in pipes caused by corrosive
water.
|
Acid Neutralization
|
There are two ways to do this:
1. Dissolves sacrificial media (limestone) to raise pH and at the same
time increases the hardness.
2. A pump injects a solution that raises the pH. The solution is usually
made by dissolving soda ash (baking soda) or potash (baking soda with potassium instead of sodium)
|
Filter
with AN (acid neutralizer) for technique #1 and solution
feed pump for technique #2.
|
|
Gas and VOC removal. Not for hydrogen sulfide removal. Radon at less
than 5000pCi/L
|
Adsorption
|
Gases attach themselves to the surface of the activated carbon. The carbon
must eventually be replaced.
|
Filter
with GAC (granular activated carbon)
|
|
Iron, manganese and hydrogen sulfide- Staining and Odor problems. hydrogen
sulfide has an odor that is usually egg like. The staining can be any color from orange to brown to black.
|
Oxidation Filtration
|
The material being removed is first oxidized . The oxidation causes
a precipitate to be formed. The precipitated material is filtered. For instance, to remove
iron the oxidation causes the dissolved iron to turn to rust and make the water cloudy red. Once the iron has rusted,
it is a particle that can be mechanically filtered.
|
Air injection systems use air for the oxidation process and chlorine
systems use chlorine for the oxidation process. Air is introduced by a venturi and chlorine maybe introduce by
either a solution feed pump or a dry pellet down the well chlorinator. The filter maybe any of the mechanical filters
mentioned above.
|
|
Hardness, iron, manganese, tannins - Hardness causes scaling. Iron and
manganese stains will have colors ranging from orange to black. Tannins will make the water tea colored.
|
Ion Exchange
|
The system simply replaces the material that is to be removed with one
that is more desirable. The total amount of material in the water does not change, only the kind of material. The
materials that are usually introduced into the water are either sodium or potassium. Chloride ions will be added
only when an anion resin is used.
|
Water Conditioner (softener) with either cation or anion resin. The anion
will only be used when there is a tannin problem. See our Kinetico water softener.
|
|
TDS, salt, nitrates, gross alpha
|
Reverse Osmosis (RO)
|
RO uses pressure to force water through a plastic membrane leaving the
minerals behind where they are flushed down the drain. Although this is not filtration, many people visualize this
as filtration on the atomic level because molecules are being separated from one another. RO is usually done at
the point of use (POU) and only for the water that will be used to drink or cook with.
|
Reverse osmosis system at either the point of use (POU) or point of entry (POE).
|
|
Radon
|
Aeration
|
Aeration drives the radon gas off by bubbling air through the water.
The agitation caused by the air removes the gas in a similar fashion to shaking a soda to make it fizz.
|
Shallow tray aeration from NEEP .
|
