Biocide
The presence of pathogens or microorganism in water is removed by
biocides like chlorine.
Deaeration
Dearation is used in water pretreatment to reduce corrosion. It is
basically used in desalination plants.
Electrodialysis
Electrodialysis is a process that is used for water treatment
especially desalination. Electric current is passed in the solution that
separates salt and impurities in the intake water. The application of
high voltage results in the transferring of impurities migrate towards
the positive and negative electrodes, thereby making water free from all
contaminants.
Ion exchange
Ion exchange treatment is usually used in desalination plant. In this
process, charged particles are removed from the solution by using an
electrical charge.
Multi-effect Distillation (MED)
Multi- effect distillation is a process in which evaporators are
aligned in different series and vapor from one series is used to
evaporate water in the next one.
Multi-stage Flash (MSF)
In Multi- stage flash distillation the feed water is pressurized and
heated. This water is then transferred to a chamber where the saturation
vapor pressure of the water is kept low. The fraction of the water is
converted into steam. The condensation of steam on the exterior surface
of heat transfer tubing results in the product warter.
Reverse Osmosis (RO)
Reverse osmosis is a process in which water is forced through the
semipermeable membrane by applying pressure thereby obtaining
concentrates and the permeates.
Scaling
It is a situation whereby salts get deposited on the interior surfaces
of a desalination plant.
Vacuum Freezing (VF)
Vacuum freezing is one of the important method of desalination. In this
process pressure and temperature of the seawater is lowered to form pure
ice crystal. The melting and washing of ice results in the production of
pure water.
Vapor Compression (VC)
Vapor compression is a form of distillation in which water is first
evaporated and then send to a compressor. The vapor is compressed by
using mechanical or thermal energy. The condensation of vapor results in
the recovery of pure product water.
Anion exchange
It is a process that is used for ion exchange. Here anion exchanger is
used which uses its anion to replace the anions of the solution.
Brine
Brine is a strong solution of salt or salts that is used for the
regeneration of ion exchange water softeners.
Cation exchange
Cation exchange is process of ion exchange in which cations in solution
are exchanged for other cations form and ion exchanger.
Coagulant
Coagulant is a material which forms a gelatinous precipitate in water.
Alum is an example of coagulant that results in the agglomeration of
finely divided particles into larger particles that is removed by
settling or filtration.
Deionization
When all ionized minerals and salts are removed from a solution by a
two-phase ion exchange procedure it is called deionization.
Disinfection
Disinfection is process that is used for killing the pathogens like
bacteria and viruses etc. Poular disinfectants that are used for the
purpose are chlorine, ozone etc.
Distillation
Distillation is a process to obtain pure water. In the process water is
first converted into vapor and then cooled and condensed to obtain fresh
and pure water.
Flocculation
When finely divided suspended solids join together to form larger
gelatinous, particles it is called flocculation.
Fouling
Fouling takes place because contaminants get accumulated in a bed of
filter media or ion exchanger, which results in the clogging of the
pores and coating surfaces thereby preventing the proper operation of
the bed.
Ultra filtration
The suspended materials and macromolecules from a solution are
separated from waste water by using Ultrafiltration process. Just like
RO process it too uses membrane and pressure differential but unlike it
does not rely on overcoming osmotic effects.
Microfiltration
Microfiltration process like Nanofiltration and Ultrafiltration removes
suspended solids from a solution using microporous membrane. The pore
size is small which range from 0.1 to 10 µm.
Nanofiltration
Nanofiltration process is used for separating various fluids or ions.
The separation layer is formed by Organic semipermeable membrane. The
important feature of this separation process is that monovalent ions
pass the membrane whereas divalent and multivalent ions are rejected.
Demineralizer
Demineralizer is used to remove various minerals like calcium,
magnesium chlorides etc from water. The consumption of these harmful
minerals can be avoided by using demineralizer.
Ion Exchange Resin
Ion exchange resins are used in ion exchange process for treating
wastewater or removing contaminants from the water. These resins come in
the form of beads, sheets, granules and are light weight porous in
nature that swells when they are immersed in liquid.
Carbon Adsorption
Carbon adsorption removes removes a soluble substance from the water.
Activated carbon is used in this process that comes in two varieties-
Powder Activated Carbon (PAC) and Granular Activated Carbon (GAC).
Water Softening Process
Hardness salts like calcium and magnesium ions in water supplied in
boilers or the cooling systems can have serious effect on their
performance. This may result in the heat loss in the boilers and the
poor cooling in re-circulating cooling systems that will enhance the
consumption of water and the heat. This may cause galvanic corrosion, in
an electrolyte. Normally the water softener uses Ion Exchange in order
to convert the hard water ions of calcium and magnesium to sodium ions.
