Industrial wastewater containing suspended organic solids pose a
threat to the aquatic biota when discharged untreated in surrounding water
bodies. The issue has become one of dire concern with increasing variation in
nature and type of solids associated with the effluent. One promising method to
treat such wastewater conveniently is using flocculants to remove the suspended
solids before discharging the water. An ideal choice for this is using polymer
based flocculants that are cost friendly and easy to use over a wide range of
suspended solids.
Flocculation
is the process by which individual particles of a suspension aggregate. They
consist of anionic, cationic and nonionic polymers of varying molecular weight.
They are used to increase the efficiency of settling, clarification, filtration
and centrifugation operations. They adsorb on particles and cause
destabilization by bridging or charge neutralization. Most common polymer used in water
treatment is made from Polyacrylamide. Polymers are
given anionic character by copolymerizing acrylamide with acrylic acid.
Anionic PAM
series products are polymer used in water treatment
that are water soluble linear chained
synthesized polymers that are insoluble in other common organic solvents. They
have valuable properties like flocculation, thickening, shear properties,
drag-reduction and dispersibility. Thus they are widely used in environmental
protection practices for the treatment of industrial wastewater containing
suspended matter; mostly coarse with high concentration of positively charged
particles under neutral or alkaline pH conditions.
Synthetic polymeric flocculants like
APAM have become very popular in industrial effluent treatment owing to their natural inertness to pH
changes, high efficiency even with low dosage, and easy handling. They are the
widespread choice as waste water treatment chemicals
for industries such as Iron & Steel, Electroplate factory, Metallurgical
workshops, coal washing etc.
Features:
Criteria
|
Benefit/Activity
|
Application
|
Organic-based wastewater
|
Treatment ability
|
Suspended and colloid particles
|
Treatment Process
|
Simpler, no pH adjustment needed
|
Sludge generation
|
Less sludge produced, may contain monomer residue
|
Treatment cost
|
Less expensive
|
Mechanism
|
Charge neutralization and concurrent bridging
|
Removal efficiency
|
TSS: 100% removal
COD: 55% removal
BOD5: 23% removal
|
APAM is most commonly available as Polyacrylamide
powder and has been tested to show no toxicity to even sensitive aquatic
species even at much higher concentrations than used in industry thus ensuring
zero environmental setbacks from tail-end runoffs into natural water bodies. ChemEqual,
the largest chemical marketplace gives the opportunity to buyer to compare and
buy chemicals and equivalents.
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