Effluent treatment is the recycling of industrial wastewater to make it reusable, aimed at preventing environmental harm and recovering valuable materials. The document details various effluent treatment methods, tests for contaminants, and procedures for assessing the quality of wastewater, including measures of toxic metals, pH, and oxygen demand. Effective treatment minimizes the adverse effects on natural water bodies and ensures compliance with environmental standards.

1. EFFLUENT TREATMENT
EFFLUENT TREATMENT
PRESENTED
PRESENTED
BY
BY
GEETHA. M.S.
GEETHA. M.S.

2. DEFINITION
DEFINITION
OBJECTIVES
OBJECTIVES
DISPOSAL OF EFFLUENTS
DISPOSAL OF EFFLUENTS
IMPORTANCE OF EFFLUENT TESTING
IMPORTANCE OF EFFLUENT TESTING
EFFLUENT TREATMENT METHODS
EFFLUENT TREATMENT METHODS

3. DEFINITION:
DEFINITION:
Effluent treatment is a process where
Effluent treatment is a process where
industrial discharged waste water is
industrial discharged waste water is
recycled and make it usable one.
recycled and make it usable one.

4. OBJECTIVES:
OBJECTIVES:
 To prevent the adverse effects of industrial wastes.
To prevent the adverse effects of industrial wastes.
 The valuable material to be recovered from effluent as
The valuable material to be recovered from effluent as
animal food and fertilizer.
animal food and fertilizer.
 Prediction of size and factory effluent testing plant.
Prediction of size and factory effluent testing plant.
 To know the amount of water used sewage waste and
To know the amount of water used sewage waste and
charge.
charge.
 To prevent the waste to mix up with natural water.
To prevent the waste to mix up with natural water.
 Toxic effluents need special treatment to prevent toxic
Toxic effluents need special treatment to prevent toxic
effect on human.
effect on human.
 Acids or alkalies leading to neutralization.
Acids or alkalies leading to neutralization.

5. Disposal of effluents
Disposal of effluents:
:
 The effluent is discharged to river and seain an
The effluent is discharged to river and seain an
untreated state.
untreated state.
 Discharged to the ground, a lagoon, a unwed
Discharged to the ground, a lagoon, a unwed
well.
well.
 Discharged as in 1or 2, the remainder is treated
Discharged as in 1or 2, the remainder is treated
at the sewage work.
at the sewage work.
 All the effluent is sent to the sewage works for
All the effluent is sent to the sewage works for
treatment and discharge.
treatment and discharge.
 Effluent is treated at the factory before
Effluent is treated at the factory before
discharge.
discharge.

6. IMPORTANCE OF EFFLUENT TESTING
IMPORTANCE OF EFFLUENT TESTING
Effluent testing is done to find out the following;
Effluent testing is done to find out the following;
o Colour- pigments, metals ions, nonmetals.
Colour- pigments, metals ions, nonmetals.
o pH- acidity/alkalinity
pH- acidity/alkalinity
o Turbidity- suspended solids, dissolved solids,
Turbidity- suspended solids, dissolved solids,
settleable solids.
settleable solids.
o Odour- volatile materials, dissolved gases, phenolic
Odour- volatile materials, dissolved gases, phenolic
compounds.
compounds.
o Oily substances and greases.
Oily substances and greases.
o Dissolved Oxygen (DO)
Dissolved Oxygen (DO)
o Biological Oxygen Demand (BOD)
Biological Oxygen Demand (BOD)
o Chemical Oxygen Demand (COD)
Chemical Oxygen Demand (COD)

7.  METALS:
METALS:
1.
1. HEXAVALENT CHROMIUM:
HEXAVALENT CHROMIUM:
DETERMINATION:
DETERMINATION:
 Hexavalent chromium is treated with
Hexavalent chromium is treated with
ammonium pyrrolidine dithiocarbamate in
ammonium pyrrolidine dithiocarbamate in
buffer solution (potassium hydrogen phthalate
buffer solution (potassium hydrogen phthalate
and sodium hydroxide solution).
and sodium hydroxide solution).
 Chromium is determined by atomic absorption
Chromium is determined by atomic absorption
spectrophotometry.
spectrophotometry.

8. 2.
2. ARSENIC:
ARSENIC:
DETERMINATION:
DETERMINATION:
 Arsenic ions are converted to gaseous
Arsenic ions are converted to gaseous
arsenic hydride, arsine by nascent hydrogen
arsenic hydride, arsine by nascent hydrogen
in acidic solution.
in acidic solution.
 Arsenic hydride reacts with silver diethyl
Arsenic hydride reacts with silver diethyl
dithiocarbamate solution in pyridine forming
dithiocarbamate solution in pyridine forming
red compound.
red compound.
 Colour is measured at 560nm.
Colour is measured at 560nm.

9. 3.
3. MERCURY:
MERCURY:
DETERMINATION:
DETERMINATION:
 Using atomic absorption photometry.
Using atomic absorption photometry.
 Waste water is treated with nitric acid and
Waste water is treated with nitric acid and
potassium dichromate solution.
potassium dichromate solution.
 Air is expelled using nitrogen/organ gas.
Air is expelled using nitrogen/organ gas.
 Sample is treated with tin (ll) chloride.
Sample is treated with tin (ll) chloride.
 Resulting mercury vapour is carried through
Resulting mercury vapour is carried through
carrier gas and determined for metal content.
carrier gas and determined for metal content.

10. 4.
4. LEAD:
LEAD:
DETERMINATION:
DETERMINATION:
 In neutral to alkaline solution, lead (ll)ions
In neutral to alkaline solution, lead (ll)ions
react with dithizone to form di-dithizonate.
react with dithizone to form di-dithizonate.
 Dithizone was treated with hydrochloric acid
Dithizone was treated with hydrochloric acid
immediately for removing excess dithizone.
immediately for removing excess dithizone.
 Dithizonate is soluble in organic solvents
Dithizonate is soluble in organic solvents
(chloroform, carbon tetrachloride)
(chloroform, carbon tetrachloride)
 Carmine red coloured organic phase is
Carmine red coloured organic phase is
measured at 620nm.
measured at 620nm.

11.  NON METALS:
NON METALS:
1.
1. CYANIDE:
CYANIDE:
DETERMINATION
DETERMINATION:
:
 Cyanides are chlorinated and subseqently
Cyanides are chlorinated and subseqently
complexed with pyridine pyroxolene to form
complexed with pyridine pyroxolene to form
coloured stable solution.
coloured stable solution.
 Colour is estimated by colorimetrically.
Colour is estimated by colorimetrically.

12. 2.
2. SULPHIDES:
SULPHIDES:
DETERMINATION:
DETERMINATION:
 Determined by iodometric titration.
Determined by iodometric titration.
 Sulphides are precipitated as cadmium
Sulphides are precipitated as cadmium
sulphide.
sulphide.
 It is treated with an acid.
It is treated with an acid.
 Hydrogen sulphide is evolved and allowed to
Hydrogen sulphide is evolved and allowed to
absorb into a measured volume of standard
absorb into a measured volume of standard
iodine solution.
iodine solution.

13. 3.
3. PHOSPHATES:
PHOSPHATES:
Determination:
Determination:
 Organic phosphorus compounds are converted to
Organic phosphorus compounds are converted to
hydrogen phosphate by sulphuric acid and
hydrogen phosphate by sulphuric acid and
hydrogen peroxide at 160
hydrogen peroxide at 1600
0
C-180
C-1800
0
C.
C.
 The phosphate is converted into ammonium
The phosphate is converted into ammonium
molybdophosphate by using ammonium molybdate.
molybdophosphate by using ammonium molybdate.
 The ammonium molybdophosphate is extracted
The ammonium molybdophosphate is extracted
with a benzene/isobutyl alcohol mixture.
with a benzene/isobutyl alcohol mixture.
 The organic phase is treated with acid tin chloride
The organic phase is treated with acid tin chloride
solution for reduction reaction.
solution for reduction reaction.
 The intense blue coloured phosphorous
The intense blue coloured phosphorous
molybdenum is measured at 625nm.
molybdenum is measured at 625nm.

14.  pH:
pH:
 Waste water sample is tested for acidity/alkalinity
Waste water sample is tested for acidity/alkalinity
using a litmus paper.
using a litmus paper.
 pH can be measured electrochemically using Ph
pH can be measured electrochemically using Ph
meter.
meter.
 ACIDITY:
ACIDITY:
 Acidity is calculated by titrating the samples with
Acidity is calculated by titrating the samples with
strong base.
strong base.
 Acidity can be neutralized by adding alkalies such as
Acidity can be neutralized by adding alkalies such as
lime and hydroxides.
lime and hydroxides.

15.  ALKALINITY:
ALKALINITY:
 It is due to presence of alkaline
It is due to presence of alkaline
substances (carbonates, hydroxides)
substances (carbonates, hydroxides)
 Reduced by adding acids.
Reduced by adding acids.
 Sulphuric acid (35%) is used.
Sulphuric acid (35%) is used.
 TURBIDITY:
TURBIDITY:
 Caused by suspended colloidal and coarse
Caused by suspended colloidal and coarse
particles.
particles.
 Measured by using nepheloturbidimeter.
Measured by using nepheloturbidimeter.

16.  SUSPENDED SOLIDS
SUSPENDED SOLIDS:
:
 Determined by filtering the waste water sample through a
Determined by filtering the waste water sample through a
previously tared sintered crucible or Gooch crucible.
previously tared sintered crucible or Gooch crucible.
 Sample is dried at 103
Sample is dried at 1030
0
C to 105
C to 1050
0
C to constant weight.
C to constant weight.
 Difference in weight of tared and final weight gives the
Difference in weight of tared and final weight gives the
suspended solids.
suspended solids.
 SETTELEABLE SOLIDS:
SETTELEABLE SOLIDS:
 Determined by allowing 1 liter of the sample to settle for about
Determined by allowing 1 liter of the sample to settle for about
1 hour at 20
1 hour at 200
0
C in Imhoff cone, which is a tapered conical tube.
C in Imhoff cone, which is a tapered conical tube.
 The volume of the settleable matter in the cone, which is
The volume of the settleable matter in the cone, which is
recorded as ml/l.
recorded as ml/l.

17. TOTAL DISSOLVED SOLIDS:
TOTAL DISSOLVED SOLIDS:
 The total solids content of a sample is
The total solids content of a sample is
determined by evaporating a known
determined by evaporating a known
volume of the waste water sample.
volume of the waste water sample.
 Dry the residue for 24 hours at 103
Dry the residue for 24 hours at 1030
0
C to
C to
105
1050
0
C followed by weighing.
C followed by weighing.
 This gives the total solid content of the
This gives the total solid content of the
sample which includes dissolved as well as
sample which includes dissolved as well as
suspended solids.
suspended solids.

18.  PHENOLIC COMPOUNDS:
PHENOLIC COMPOUNDS:
DETERMINATION:
DETERMINATION:
 Phenolic compounds are isolated by steam
Phenolic compounds are isolated by steam
distillation.
distillation.
 The distillate is acidified to a pH of less
The distillate is acidified to a pH of less
than 4.0
than 4.0
 Then copper sulphate solution is added.
Then copper sulphate solution is added.
 To this amino antipyrine solution is added.
To this amino antipyrine solution is added.
 The reaction mixture is extracted with
The reaction mixture is extracted with
chloroform.
chloroform.
 The colour of the chloroform layer is
The colour of the chloroform layer is
measured at 460nm.
measured at 460nm.

19.  DISSOLVED OXYGEN (DO):
DISSOLVED OXYGEN (DO):
PRINCIPLE:
PRINCIPLE:
 Determined iodometrically by the modified Winkler’s
Determined iodometrically by the modified Winkler’s
method.
method.
 When manganous sulphate is added to the water
When manganous sulphate is added to the water
sample containing alkaline potassium iodide thereby
sample containing alkaline potassium iodide thereby
manganese hydroxide is formed.
manganese hydroxide is formed.
 This is oxidised to basic manganic oxide by the
This is oxidised to basic manganic oxide by the
dissolved oxygen present in the water sample.
dissolved oxygen present in the water sample.
 When sulphuric acid is added, the basic manganic
When sulphuric acid is added, the basic manganic
oxide liberates iodine which is equivalent to the
oxide liberates iodine which is equivalent to the
dissolved oxygen originally present in the water
dissolved oxygen originally present in the water
sample.
sample.
 Liberated iodine is titrated with standard hypo solution
Liberated iodine is titrated with standard hypo solution
(thiosulphate solution) using starch as indicator.
(thiosulphate solution) using starch as indicator.

20.  BIOLOGICAL OXYGEN DEMAND:
BIOLOGICAL OXYGEN DEMAND:
Biological oxygen demand represents the quantity of
Biological oxygen demand represents the quantity of
oxygen required by bacteria and other microorganisms
oxygen required by bacteria and other microorganisms
during the biochemical degradation and transformation
during the biochemical degradation and transformation
of organic matter present in the waste water under
of organic matter present in the waste water under
aerobic conditions.
aerobic conditions.
PRINCIPLE:
PRINCIPLE:
 BOD test essentially consists of measurement of
BOD test essentially consists of measurement of
dissolved oxygen content of the sample before and
dissolved oxygen content of the sample before and
after incubation at 20
after incubation at 200
0
c for 5 days.
c for 5 days.
 The BOD is usually expressed as mg/l (5 days at
The BOD is usually expressed as mg/l (5 days at
20
200
0
c)
c)
 Normal water contains BOD less than or equal
Normal water contains BOD less than or equal
10mg/l of dissolved oxygen.
10mg/l of dissolved oxygen.
 Excess BOD makes water toxic.
Excess BOD makes water toxic.

21.  CHEMICAL OXYGEN DEMAND (COD):
CHEMICAL OXYGEN DEMAND (COD):
The chemical oxygen demand (COD) is a measure
The chemical oxygen demand (COD) is a measure
of the oxygen equivalent to that portion of organic
of the oxygen equivalent to that portion of organic
matter present in the waste water sample that is
matter present in the waste water sample that is
susceptible to oxidation by potassium dichromate.
susceptible to oxidation by potassium dichromate.
PRINCIPLE:
PRINCIPLE:
 When the waste water sample is refluxed with a
When the waste water sample is refluxed with a
known excess of potassium dichromate in a 50%
known excess of potassium dichromate in a 50%
sulphuric acid solution in presence of Agso
sulphuric acid solution in presence of Agso4
4 (catalyst)
(catalyst)
to eliminate the interference due to chloride.
to eliminate the interference due to chloride.
 The organic matter of the sample is oxidised to H
The organic matter of the sample is oxidised to H2
2O,
O,
CO
CO2
2, NH
, NH3
3.
.
 The organic matter remaining unreacted in the
The organic matter remaining unreacted in the
solution is titrated with a standard solution of ferrous
solution is titrated with a standard solution of ferrous
ammonium sulphate.
ammonium sulphate.

22. COD of the sample is calculated using
COD of the sample is calculated using
following formula.
following formula.
COD (mg/l)=
COD (mg/l)= (V1-V2)XNX8X1000
(V1-V2)XNX8X1000
X
X
Where,
Where,
V1=Volume of ferrous ammonium sulphate
V1=Volume of ferrous ammonium sulphate
solution consumed in blank.
solution consumed in blank.
V2=Volume of ferrous ammonium sulphate
V2=Volume of ferrous ammonium sulphate
solution consumed in test solution.
solution consumed in test solution.
X=Volume of sample taken.
X=Volume of sample taken.
N=Normality of ferrous ammonium sulphate
N=Normality of ferrous ammonium sulphate
solutuion.
solutuion.

23. EFFLUENT TREATMENT METHODS:
EFFLUENT TREATMENT METHODS:
Pretreatment
Equalization
Neutralization
Grease and oil removal
Removal of toxic substances
Screens
Grit chamber
Gravity sedimentation tank
Chemical reactions
Primary treatment
Activated sludge process
Trickling filtration process
Aerated lagoons
Oxidation ditch or ponds
Coagulation, flocculation
Coprecipitation
Filtration
Adsorption
Ion-exchange
Secondary treatment
Tertiary treatment

24.  PRETREATMENT:
PRETREATMENT:
Pretreatment process is attempted to render
Pretreatment process is attempted to render
the effluent for further treatment.
the effluent for further treatment.
1)
1) EQUALIZATION:
EQUALIZATION:
In this process, concentrated waste is diluted,
In this process, concentrated waste is diluted,
if necessary.
if necessary.
It can be done by following methods:
It can be done by following methods:
 Mechanical mixing is required, if waste
Mechanical mixing is required, if waste
water is purely chemical in its reactivity.
water is purely chemical in its reactivity.
 Aeration mixing is required, if waste water
Aeration mixing is required, if waste water
is biodegradable.
is biodegradable.
Basins of appropriate size are used for eqalization.
Basins of appropriate size are used for eqalization.

25. 2)
2) NEUTRALIZATION:
NEUTRALIZATION:
 Prior to the treatment, acidic or basic waste
Prior to the treatment, acidic or basic waste
water must be neutralized.
water must be neutralized.
 If the industry produces acidic as well as
If the industry produces acidic as well as
basic wastes, these waste water can be
basic wastes, these waste water can be
mixed together into a proper ratio to obtain
mixed together into a proper ratio to obtain
neutral pH levels.
neutral pH levels.
 Equalization basins can be used for
Equalization basins can be used for
neutralization.
neutralization.
3)
3) REMOVAL OF GREASES AND OILS:
REMOVAL OF GREASES AND OILS:
 These tend to form an insoluble layer on the
These tend to form an insoluble layer on the
water surface.
water surface.
 These can be removed using grease traps,
These can be removed using grease traps,
gravity methods, skimming methods.
gravity methods, skimming methods.

26. 4)
4) REMOVAL OF TOXIC SUBSTANCES:
REMOVAL OF TOXIC SUBSTANCES:
 Pretreatment is essential to reduce the
Pretreatment is essential to reduce the
concentration of heavy metals to below its
concentration of heavy metals to below its
toxic levels.
toxic levels.
 If heavy metals cannot be reused, they
If heavy metals cannot be reused, they
must be concentrated and removed as
must be concentrated and removed as
insoluble materials.
insoluble materials.
 Organic molecules can be destroyed by
Organic molecules can be destroyed by
oxidation systems or incineration (burning
oxidation systems or incineration (burning
in air)
in air)

27.  PRIMARY TREATMENT:
PRIMARY TREATMENT:
It involves the removal of large floating
It involves the removal of large floating
or suspended particles (fibres, glass pieces,
or suspended particles (fibres, glass pieces,
wooden pieces, hard materials) first by
wooden pieces, hard materials) first by
physical and then by chemical treatments.
physical and then by chemical treatments.
1)
1) SCREENS:
SCREENS:
 Large particles are removed mechanically by
Large particles are removed mechanically by
passing waste water through fixed or movable
passing waste water through fixed or movable
screens.
screens.
 Different types of screens are used, such as,
Different types of screens are used, such as,
Bar screen, Hand raked or mechanically racked
Bar screen, Hand raked or mechanically racked
screen.
screen.

28. 2)
2) GRIT CHAMBERS:
GRIT CHAMBERS:
Grit (small particles, stones) chambers are
Grit (small particles, stones) chambers are
used for the removal of heavy and inert
used for the removal of heavy and inert
particles by centrifugal action and friction
particles by centrifugal action and friction
against tank walls.
against tank walls.
 Grit should be removed so as to protect
Grit should be removed so as to protect
against any damage of pumps and other
against any damage of pumps and other
equipments by abrasion and also to avoid
equipments by abrasion and also to avoid
settling in pipe bends and channels.
settling in pipe bends and channels.
 Floatable solids are removed in the aerated grit
Floatable solids are removed in the aerated grit
chamber.
chamber.

29. 3)
3) GRAVITY SEDIMENTATION TANK:
GRAVITY SEDIMENTATION TANK:
 The suspended particles can be removed
The suspended particles can be removed
effectively and economically by sedimentation.
effectively and economically by sedimentation.
 Useful for the treatment of waste containing
Useful for the treatment of waste containing
high percentage of settleable solids.
high percentage of settleable solids.

30. Aerted grit
chamber
grit
air Floatable solute
H
E
A
V
Y
S
O
L
I
D
S
Circular sedimentation tank
Influent
Sludge
Sludge collector
Scum collector
circular inlet
baffle
effluent
Screw grit conveyor
Grit
Diffusion current

31. 4)
4) CHEMICAL REACTIONS:
CHEMICAL REACTIONS:
Coagulation, flocculation, precipitation:
Coagulation, flocculation, precipitation:
 These processes involve agglomeration of tiny
These processes involve agglomeration of tiny
particles into large particles, so that
particles into large particles, so that
sedimentation will be rapid.
sedimentation will be rapid.
 Light weight and colloidal solids are removed by
Light weight and colloidal solids are removed by
chemical means followed by gravity sedimentation.
chemical means followed by gravity sedimentation.
 Flocculating agents (coagulating) are, ferric
Flocculating agents (coagulating) are, ferric
chloride, aluminium sulphate, ferrous sulphite, lime.
chloride, aluminium sulphate, ferrous sulphite, lime.
 Coagulation aids, such as activated silica, a
Coagulation aids, such as activated silica, a
acrylic and methacrylic polymers are added to
acrylic and methacrylic polymers are added to
promote the formation of large and quick settling
promote the formation of large and quick settling
floc.
floc.

32.  SECONDARY TREATMENT:
SECONDARY TREATMENT:
It is a biological process in which bacteria
It is a biological process in which bacteria
and other microorganisms utilize the components
and other microorganisms utilize the components
present in the waste water as nutrients for their
present in the waste water as nutrients for their
growth.
growth.
1)
1) ACTIVATED SLUDGE PROCESS:
ACTIVATED SLUDGE PROCESS:
 In this process the microbial floc is suspended in
In this process the microbial floc is suspended in
an open tank and aerated about 6 to 24 hours.
an open tank and aerated about 6 to 24 hours.
 Molecular oxygen (air) is continuously supplied by
Molecular oxygen (air) is continuously supplied by
mechanical means into the tank.
mechanical means into the tank.
 When industrial waste is aerated, biological
When industrial waste is aerated, biological
degradation of waste into CO
degradation of waste into CO2
2 and H2
and H2O
O
takesplace.
takesplace.
 Bacterial flora grows and remains suspended in
Bacterial flora grows and remains suspended in
the form of a floc, which is called as ‘
the form of a floc, which is called as ‘activated
activated
sludge
sludge’.
’.

34. 2)
2) TRICKLING FILTRATION
TRICKLING FILTRATION:
:
 In this process microorganisms are attached to a
In this process microorganisms are attached to a
fixed bed rather than floating and remain
fixed bed rather than floating and remain
suspended.
suspended.
 The bacterial mass forms a gelatinous film.
The bacterial mass forms a gelatinous film.
 Using rotary sprinklers, effluent is sprayed and
Using rotary sprinklers, effluent is sprayed and
distributed evenly over the surface (i.e.trickling).
distributed evenly over the surface (i.e.trickling).
 Trickling filter is provided with slots at bottom for
Trickling filter is provided with slots at bottom for
the air inlet.
the air inlet.
 On the surface aerobic metabolism occurs.
On the surface aerobic metabolism occurs.
 At the bottom of the layer anaerobic metabolism
At the bottom of the layer anaerobic metabolism
occurs due to lack of oxygen.
occurs due to lack of oxygen.
 Secondary settling basin is installed.
Secondary settling basin is installed.

36. 3)
3) AERATED LAGOONS
AERATED LAGOONS:
:
 These permit the conversion of organic
These permit the conversion of organic
components in the waste water by microbes
components in the waste water by microbes
without stabilization.
without stabilization.
 Mixing is achieved as a result of gas production
Mixing is achieved as a result of gas production
from bacterial metabolism and wind action.
from bacterial metabolism and wind action.
 Discharge is allowed into solid separation
Discharge is allowed into solid separation
ponds.
ponds.
 After about 3 to 6 days, flocculated sludge is
After about 3 to 6 days, flocculated sludge is
formed and oxidation of organic matter starts.
formed and oxidation of organic matter starts.
 It removes about 80% of BOD.
It removes about 80% of BOD.

37. 4)
4) OXIDATION DITCH OR POND
OXIDATION DITCH OR POND:
:
 These are relatively less shallow than
These are relatively less shallow than
aerated lagoons.
aerated lagoons.
 Solids in waste settle at the bottom and
Solids in waste settle at the bottom and
form thin layer, which acts as anaerobic
form thin layer, which acts as anaerobic
layer.
layer.
 Anaerobic bacteria convert organic matter
Anaerobic bacteria convert organic matter
to methane, carbon dioxide, ammonia.
to methane, carbon dioxide, ammonia.
 Final discharge should be separately
Final discharge should be separately
 Disinfected to avoid pollution due to
Disinfected to avoid pollution due to
microorganisms.
microorganisms.

38.  TERTIARY TREAMENT
TERTIARY TREAMENT:
:
1.
1. COAGULATION
COAGULATION
2.
2. COPRECIPITATION
COPRECIPITATION
3.
3. ADSORPTION
ADSORPTION
4.
4. ION EXCHANGE
ION EXCHANGE
5.
5. FILTRATION
FILTRATION

39. 1.
1. Coagulation
Coagulation:
: The reaction that takes place
The reaction that takes place
upon the addition of coagulant is called
upon the addition of coagulant is called
coagulation.
coagulation.
Ex: Metal salts organic polymers.
Ex: Metal salts organic polymers.
2.
2. Co precipitation
Co precipitation: It is a process in which ions
: It is a process in which ions
in solution phase are allowed to precipitate
in solution phase are allowed to precipitate
with the carrier molecule either by adsorption
with the carrier molecule either by adsorption
method or inclusion method.
method or inclusion method.
3.
3. Adsorption
Adsorption: Treatment of effluent with
: Treatment of effluent with
activated carbon is called adsorption.
activated carbon is called adsorption.
This is particularly useful for removal of
This is particularly useful for removal of
pesticides and carbamates.
pesticides and carbamates.