Ch4 Water Treatment II Coag

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Water treatment:Water treatment:Water treatment:Water treatment:Water treatment:Water treatment:Water treatment:Water treatment:

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Sudha Goel, Ph.D.Sudha Goel, Ph.D.Sudha Goel, Ph.D.Sudha Goel, Ph.D.Sudha Goel, Ph.D.Sudha Goel, Ph.D.Sudha Goel, Ph.D.Sudha Goel, Ph.D.

Dept. of Civil Eng., IITKgp Dept. of Civil Eng., IITKgp Dept. of Civil Eng., IITKgp Dept. of Civil Eng., IITKgp Dept. of Civil Eng., IITKgp Dept. of Civil Eng., IITKgp Dept. of Civil Eng., IITKgp Dept. of Civil Eng., IITKgp Kharagpur 721 302 Kharagpur 721 302 Kharagpur 721 302 Kharagpur 721 302 Kharagpur 721 302 Kharagpur 721 302 Kharagpur 721 302 Kharagpur 721 302



Particle sizesParticle sizesParticle sizesParticle sizesParticle sizesParticle sizesParticle sizesParticle sizes

Stable particles that mustStable particles that mustStable particles that mustStable particles that must

be chemically andbe chemically andbe chemically andbe chemically and

2QMZ, 2000

Discrete particles canDiscrete particles canDiscrete particles canDiscrete particles can

be removed bybe removed bybe removed bybe removed by

settlingsettlingsettlingsettling

removalremovalremovalremoval



Colloids and stable suspensionsColloids and stable suspensionsColloids and stable suspensionsColloids and stable suspensionsColloids and stable suspensionsColloids and stable suspensionsColloids and stable suspensionsColloids and stable suspensions ColloidsColloidsColloidsColloids: particles that do not settle under the influence of

gravity but remain stable in suspension in a fluid medium

Size range: 1 nm to 1 micron (or even 10 microns) Inorganic particles like asbestos fibers, silt, clay particles

Organic particles: NOM (humic and non-humic substances),viruses bacteria lankton microbes

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Particles in natural watersParticles in natural watersParticles in natural watersParticles in natural waters (generally in pH range of 6 to 8) arenegatively charged

Stable particlesStable particlesStable particlesStable particles: Like charges repel each other and remainsuspended in solution indefinitely

No aggregation is possible due to net repulsive energybetween them

Examples: Silt in rivers, turbidity of lake waters, andground waters



Coagulation and flocculationCoagulation and flocculationCoagulation and flocculationCoagulation and flocculationCoagulation and flocculationCoagulation and flocculationCoagulation and flocculationCoagulation and flocculation Process for combining small particles (colloids) into larger,Process for combining small particles (colloids) into larger,Process for combining small particles (colloids) into larger,Process for combining small particles (colloids) into larger,

settleable aggregates (flocs)settleable aggregates (flocs)settleable aggregates (flocs)settleable aggregates (flocs) Addition of coagulants like Al or Fe salts, organic polymers to

‘destabilize’ particles so that they will aggregate, form floc and settle Primary objective in water treatmentPrimary objective in water treatmentPrimary objective in water treatmentPrimary objective in water treatment: Removal of turbidity

(particles) and suspended solids (SS) Light is scattered most easily by colloidal suspensions

4

oagu a on o ows se men a on an screen ng w ere arger eav er particles or floc are removed by discrete settling

Design objective is removal of colloidal particles (1 nm to 1Design objective is removal of colloidal particles (1 nm to 1Design objective is removal of colloidal particles (1 nm to 1Design objective is removal of colloidal particles (1 nm to 1micron)micron)micron)micron)

Can remove bacteria, soil, sand and clay particles

Concomitant removal of associated compounds or smaller particles like NOM, heavy metals, pesticides, etc. Enhanced coagulation: when an elevated coagulant dose (higher

than the optimum required for turbidity removal) is used to remove

TOC (or NOM) to ensure that DBP conc are not exceeded



ConcomitantremovalofvariousotherwatercomponentsoccursConcomitantremovalofvariousotherwatercomponentsoccursConcomitantremovalofvariousotherwatercomponentsoccursConcomitantremovalofvariousotherwatercomponentsoccursduringcoagulationduringcoagulationduringcoagulationduringcoagulation NOM:NOM:NOM:NOM: organicmatterofnaturalorigin- canbealgalmaterialorhumicmaterial

Algalmatter: Algalmatter: Algalmatter: Algalmatter: freshOMthathasnotbeenrecycledthro’theCcycle;largelyaliphaticandlowMW

HumicsubstancesHumicsubstancesHumicsubstancesHumicsubstances:derivedfromoldvegetation,complexorganicmatterthatisrelativelyresistanttobiodegradationduetoseveral

CoagulationCoagulationCoagulationCoagulationCoagulationCoagulationCoagulationCoagulation

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recyc est ro t e cyc e; arge yaromat can g PrecursorsfortheformationofDBPsduringchlorination

Color,odorandtaste-impartingcompounds/chemicals

Sequestersheavymetals,responsibleforbacterialregrowth

MicroorganismsMicroorganismsMicroorganismsMicroorganisms

Soil,sandandclayparticlesSoil,sandandclayparticlesSoil,sandandclayparticlesSoil,sandandclayparticles

Toxicsubstances(canbenaturaloranthropogenic)Toxicsubstances(canbenaturaloranthropogenic)Toxicsubstances(canbenaturaloranthropogenic)Toxicsubstances(canbenaturaloranthropogenic) Heavymetals

SOCslikepesticides,andVOCs



Suspended versus dissolved solidsSuspended versus dissolved solidsSuspended versus dissolved solidsSuspended versus dissolved solidsSuspended versus dissolved solidsSuspended versus dissolved solidsSuspended versus dissolved solidsSuspended versus dissolved solids Distinction between dissolved and suspended solids varies greatly in the

literature.

There are no theoretical cut-offs for these particles

Can only have a cutoff defined based on operational convenience

Choice of filter pore size (anywhere from 1.5 micron to 0.2 micron) isbased on operational requirement or objective.

Colloids fall into either category ‘operationally’ speaking.

6

Standard methods Dissolved solids are measured after filtration through glass fiber

filters (no ash residue on burning)

Recommended filters: Whatman 934AH has nominal pore size of 1.5 micron; Millipore AP40 -?

Bacteriological requirements Separation of bacteria from water (especially drinking water

samples) requires much smaller pore sizes

0.2 microns ensures bacterial removal

0.45 microns is often used by researchers





Coagulation, Flocculation and PrecipitationCoagulation, Flocculation and PrecipitationCoagulation, Flocculation and PrecipitationCoagulation, Flocculation and PrecipitationCoagulation, Flocculation and PrecipitationCoagulation, Flocculation and PrecipitationCoagulation, Flocculation and PrecipitationCoagulation, Flocculation and Precipitation

Coagulation:Coagulation:Coagulation:Coagulation: chemical conditioning of particleschemical conditioning of particleschemical conditioning of particleschemical conditioning of particles

Destabilization and change in physicoDestabilization and change in physicoDestabilization and change in physicoDestabilization and change in physico----chemicalchemicalchemicalchemicalproperties of colloidal particlesproperties of colloidal particlesproperties of colloidal particlesproperties of colloidal particles

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Gentle mixing of destabilized suspensions to accelerateGentle mixing of destabilized suspensions to accelerateGentle mixing of destabilized suspensions to accelerateGentle mixing of destabilized suspensions to accelerateinterparticle contact, promoting aggregation and settlinginterparticle contact, promoting aggregation and settlinginterparticle contact, promoting aggregation and settlinginterparticle contact, promoting aggregation and settling

PrecipitationPrecipitationPrecipitationPrecipitation:::: Dissolved minerals (TDS) like Ca, Mg in water can beDissolved minerals (TDS) like Ca, Mg in water can beDissolved minerals (TDS) like Ca, Mg in water can beDissolved minerals (TDS) like Ca, Mg in water can be

precipitated as SS by addition of chemicals like lime andprecipitated as SS by addition of chemicals like lime andprecipitated as SS by addition of chemicals like lime andprecipitated as SS by addition of chemicals like lime andsoda ashsoda ashsoda ashsoda ash

QMZ, 2000





StericstabilizationStericstabilizationStericstabilizationStericstabilizationStericstabilizationStericstabilizationStericstabilizationStericstabilization

• Adsorptionofpolymersat

solid-waterinterfaces

• hydrophobicand

hydrophilicparts

• quantitativeformulation

difficultunlikeDLmodel• Repulsioncanoccur

duetotwoprocesses

• compression

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• interpenetration• Usedinthemanufactureof

paintsandwaxes

• NOMismainlyhumic

material

• Anionicpolyelectrolytes

• adsorbatinterfaces

• surfaceactive

• contributestoparticle

stabilitybystericeffectsAmirtharajah and O’Melia, 1990



Colloidal particlesColloidal particlesColloidal particlesColloidal particlesColloidal particlesColloidal particlesColloidal particlesColloidal particles

11Colloidal particles are those that do not settle; they remain in ‘stable’ suspension

QMZ, 2000



Electric potentialElectric potentialElectric potentialElectric potential

surroundingsurroundingsurroundingsurrounding

particleparticleparticleparticle

Double layer Double layer Double layer Double layer Double layer Double layer Double layer Double layer modelmodelmodelmodelmodelmodelmodelmodel

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Rigid layer attached to particle surfaceRigid layer attached to particle surfaceRigid layer attached to particle surfaceRigid layer attached to particle surface

fixed or Stern layer fixed or Stern layer fixed or Stern layer fixed or Stern layer

Nernst PotentialNernst PotentialNernst PotentialNernst Potential

Zeta PotentialZeta PotentialZeta PotentialZeta Potential

PlanePlanePlanePlane

of of of of shear shear shear shear

Bulk solutionBulk solutionBulk solutionBulk solutionDiffuse layer Diffuse layer Diffuse layer Diffuse layer



Zeta potential or electrokinetic potentialZeta potential or electrokinetic potentialZeta potential or electrokinetic potentialZeta potential or electrokinetic potentialZeta potential or electrokinetic potentialZeta potential or electrokinetic potentialZeta potential or electrokinetic potentialZeta potential or electrokinetic potential: Potential that

causes charged particles to move towards an oppositely

charged electrode and is associated with the plane of

shear of the fluid around the particles

Double layer modelDouble layer modelDouble layer modelDouble layer modelDouble layer modelDouble layer modelDouble layer modelDouble layer model

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Location of slipping or shear plane is assumed to be theouter border of the Stern layer Stern layer Stern layer Stern layer (Lyklema 1978)

Zeta potentialZeta potentialZeta potentialZeta potentialZeta potentialZeta potentialZeta potentialZeta potential is used to measure particle charge

GouyGouyGouyGouy----Chapman modelChapman modelChapman modelChapman model is a mathematical description of thedouble layer theory

Amirtharajah and O’Melia, 1990



Double layer modelDouble layer modelDouble layer modelDouble layer modelDouble layer modelDouble layer modelDouble layer modelDouble layer model Accumulation of counter ions on and around a charged particle results in Accumulation of counter ions on and around a charged particle results in Accumulation of counter ions on and around a charged particle results in Accumulation of counter ions on and around a charged particle results in

two electrical double layerstwo electrical double layerstwo electrical double layerstwo electrical double layers

A fixed, rigid (Stern) layer is formed and remains attached to the particlesurface

Diffuse layer formed due to

Electrostatic attraction and repulsion, resulting in electrical potential

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– , , ……

Thermal and molecular diffusion against conc gradients produced byelectrostatic forces

Van der Waal’s forces – independent of solution composition, f(kindand # of atoms in soln)

Drawbacks of modelDrawbacks of modelDrawbacks of modelDrawbacks of model Ions are treated as point charges, and have no physical or chemical

characteristics

Does not differentiate between coagulants that have the same charge

but different coagulating properties (see Fig 6.6)



15QMZ, 2000QMZ, 2000QMZ, 2000QMZ, 2000

Double layer Double layer Double layer Double layer Double layer Double layer Double layer Double layer compressioncompressioncompressioncompressioncompressioncompressioncompressioncompression



16Amirtharajah and O’Melia, 1990



Increase in solution I results in higher conc of counterions in the diffuseIncrease in solution I results in higher conc of counterions in the diffuseIncrease in solution I results in higher conc of counterions in the diffuseIncrease in solution I results in higher conc of counterions in the diffuse

layer layer layer layer Volume of diffuse layer required to maintain electroneutrality

reduces

Destabilization of colloidsDestabilization of colloidsDestabilization of colloidsDestabilization of colloidsDestabilization of colloidsDestabilization of colloidsDestabilization of colloidsDestabilization of colloids

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Example: when freshwater (low I) meets seawater (high I) – particlesin freshwater (silt) get destabilized and settle forming deltas

As double layer gets compressed As double layer gets compressed As double layer gets compressed As double layer gets compressed

Particles can come closer to each other (electrostatic repulsion is

reduced)

VDW forces dominate and net interaction energy becomes attractive

rather than repulsive



Destabilization of colloidsDestabilization of colloidsDestabilization of colloidsDestabilization of colloidsDestabilization of colloidsDestabilization of colloidsDestabilization of colloidsDestabilization of colloids

ChemicalcoagulantscausedestabilizationofparticlesChemicalcoagulantscausedestabilizationofparticlesChemicalcoagulantscausedestabilizationofparticlesChemicalcoagulantscausedestabilizationofparticles

MechanismsofdestabilizationMechanismsofdestabilizationMechanismsofdestabilizationMechanismsofdestabilization

Compressionofdoublelayerandelectrostaticattraction

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Enmeshmentinprecipitate– sweepflocformation

Adsorptiontopermitinterparticlebridging









QMZ, 2000

22QMZ, 2000QMZ, 2000QMZ, 2000QMZ, 2000



Adsorption and charge neutralizationAdsorption and charge neutralizationAdsorption and charge neutralizationAdsorption and charge neutralizationAdsorption and charge neutralizationAdsorption and charge neutralizationAdsorption and charge neutralizationAdsorption and charge neutralization Chargeneutralization(QMZ):Chargeneutralization(QMZ):Chargeneutralization(QMZ):Chargeneutralization(QMZ): AdditionofAlorFesaltsandorganicpolymersprovideshighconcentrationsofcounterionsthatneutralizenegativesurfacechargesonparticles

Netattractiveforcesleadtoaggregation,andsettlingofaggregatesorfloc

ChemicalbondsbetweencolloidandcoagulantcanovershadowESChemicalbondsbetweencolloidandcoagulantcanovershadowESChemicalbondsbetweencolloidandcoagulantcanovershadowESChemicalbondsbetweencolloidandcoagulantcanovershadowESforcesforcesforcesforces

23

restabilization)areexamplesofthechemicalinteractionsbetweencolloidsandcoagulants

Destabilizationofparticles(theiraggregation)happensatlowcoagulantconcduetoESforces

Energyinvolvedinelectrostatic(ES)interactionsbetweencolloidandEnergyinvolvedinelectrostatic(ES)interactionsbetweencolloidandEnergyinvolvedinelectrostatic(ES)interactionsbetweencolloidandEnergyinvolvedinelectrostatic(ES)interactionsbetweencolloidand

coagulantioncoagulantioncoagulantioncoagulantion Foramonovalentcounterionandaparticlewithapotentialdifferenceof100mV,theattractiveESenergy=9.6kJ/mol

Comparewithcovalentbondenergiesof200to400kJ/mol

Hbondenergiesof20kJ/mol



Sweep floc formationSweep floc formationSweep floc formationSweep floc formationSweep floc formationSweep floc formationSweep floc formationSweep floc formation

Precipitationofsaltsathighconcentration

theprecipitate‘sweeps’colloidalparticlesalongwithitselfwhilesettling

Enmeshmentofcolloidalparticlesinprecipitatingcoagulants

24

Usedforremovalofturbidity,colorandTOC Forlowturbidityandcolorwaters:solids(coagulantaidslikeactivatedsilica,kaolinite)areaddedalongwithalumtoimprovephysicalflocculationkinetics

Highcoagulantsaltconcwillresultinformationoftherespectivemetalhydroxides

AlorFehydroxides



Adsorption and Adsorption and Adsorption and Adsorption and Adsorption and Adsorption and Adsorption and Adsorption and

interparticleinterparticleinterparticleinterparticleinterparticleinterparticleinterparticleinterparticle

bridgingbridgingbridgingbridgingbridgingbridgingbridgingbridging

Polymers attach

25PRT 1985PRT 1985PRT 1985PRT 1985

particle leading toaggregation and

floc formation



Coagulation processCoagulation processCoagulation processCoagulation processCoagulation processCoagulation processCoagulation processCoagulation process1. Coagulantformation

• Al3+ andSO42- ionsformedonadditionofalumarenottheoperativecoagulants

• Resultingpolymericoxyhydroxidespeciesarethecoagulants

• Pre-formedcoagulantsalsoexistlikeactivatedsilica,SOPs,PACl

26

(polyaluminumchloride)andPICl(polyironchloride)

2. Particledestabilization

3. Interparticlecollisions

Processes1and2occurinrapid-mixtanks,chemicalconditioningofcolloidstoinduceaggregationofparticlesintosmallfloc

Process3occursbyslowmixingintheflocculationtank;physicalconditioningofsmallaggregatestoformlargeflocthatwillsettle

Amirtharajah and O’Melia, 1990




Al, Fe and Si polymeric species and pH reduction on addition of these salts Al, Fe and Si polymeric species and pH reduction on addition of these salts Al, Fe and Si polymeric species and pH reduction on addition of these salts Al, Fe and Si polymeric species and pH reduction on addition of these salts




See fig 4.17 (SMP) for Zn and problems for Al and Fe



29Amirtharajah and O’Melia, 1990 Stumm and Morgan, 1981



Coagulation practiceCoagulation practiceCoagulation practiceCoagulation practiceCoagulation practiceCoagulation practiceCoagulation practiceCoagulation practice Alum doses are generally in the range of 5 to 50 mg/L Effective from pH of 5 to 7.5 (see solubility diagram)

Ferric chloride Effective from pH 4.5 to 9

Surface waters can be grouped into 4 categories Group 1: high turbidity – low alkalinity

Lowering of pH makes coagulation more effective, but neutralization maybecome necessary

30

Group 2: high turbidity – high alkalinity Buffering by alkalinity is adequate for maintaining pH

Adsorption and charge neutralization will be less effective than in lowalkalinity waters

Higher coagulant dose for sweep floc formation

Group 3: low turbidity – high alkalinity Colloid conc is low, therefore adding turbidity causing particles like clay will

improve coagulation (can reduce coagulant dose req.)

Group 4: low turbidity – low alkalinity Additional turbidity or alkalinity has to be added to improve coagulation;

better to add both; direct filtration instead of settling followed by filtration is

another good option (microfloc formation)PRT 1985PRT 1985PRT 1985PRT 1985

PRT 1985PRT 1985PRT 1985PRT 1985



PRT 1985PRT 1985PRT 1985PRT 1985

31



Particle Transport ProcessesParticle Transport ProcessesParticle Transport ProcessesParticle Transport ProcessesParticle Transport ProcessesParticle Transport ProcessesParticle Transport ProcessesParticle Transport Processes Aggregation of destabilized colloids requires flocculation

Flocculation is based on enhancing interparticle collisions

Greater the number of collisions, greater the probability that the particleswill aggregate and floc will be formed

Three physical processes for interparticle collisions to occur 1. Brownian diffusion (perikinetic flocculation)

Random motion of particles due to collision with water molecules

’

32

constant and T= abs temp, deg K2. Fluid shear (orthokinetic flocculation)

Driving force is velocity gradient (G) in either laminar or turbulent fluidfields

Gt = design parameter = measure of the relative velocity of twoGt = design parameter = measure of the relative velocity of twoGt = design parameter = measure of the relative velocity of twoGt = design parameter = measure of the relative velocity of two

particles of fluid and the distance between themparticles of fluid and the distance between themparticles of fluid and the distance between themparticles of fluid and the distance between them Gt values range from 104 to 105 for t ranging from 10 to 30 min

3. Differential settling

Vertical transport of particles results in collisions

Driving force is gravity, controlling parameter is settling velocity of particle



Flocculation or mixingFlocculation or mixingFlocculation or mixingFlocculation or mixing

Rapid mixing: for mixing the coagulant

Detention time is approx. 0.5 min, ideally should be 2 min

Impellers or in line blenders

Conventional drinking water treatmentConventional drinking water treatmentConventional drinking water treatmentConventional drinking water treatmentConventional drinking water treatmentConventional drinking water treatmentConventional drinking water treatmentConventional drinking water treatment

processes: flocculationprocesses: flocculationprocesses: flocculationprocesses: flocculationprocesses: flocculationprocesses: flocculationprocesses: flocculationprocesses: flocculation

33

es va ues: o s- mpe ers an , o , s-

(in line blenders)

Slow mixing: for floc formation

Detention time of approx. 0.5 h

Too fast will break floc; should be slow enough to maximizenumber of particle collisions

Optimum speed has to be determined

QMZ, 2000



Velocity gradientsVelocity gradientsVelocity gradientsVelocity gradientsVelocity gradientsVelocity gradientsVelocity gradientsVelocity gradients Power dissipation per unit volume (eq 4-14)

34



ImpellersImpellersImpellersImpellersImpellersImpellersImpellersImpellers

35PRT 1985PRT 1985PRT 1985PRT 1985



Design considerationsDesign considerationsDesign considerationsDesign considerationsDesign considerationsDesign considerationsDesign considerationsDesign considerations

Coagulation: determine optimum coagulant dose for

turbidity removal or for turbidity and TOC removal

Flocculation: design of rapid mix and flocculation basins

36

clarifiers



Clariflocculator Clariflocculator Clariflocculator Clariflocculator Clariflocculator Clariflocculator Clariflocculator Clariflocculator

37http://www.environengg.com/clariflocculators.html



Circular clariflocculator Circular clariflocculator Circular clariflocculator Circular clariflocculator Circular clariflocculator Circular clariflocculator Circular clariflocculator Circular clariflocculator

38Source: Internet(msu)



Plate and tube settlers (M&E)Plate and tube settlers (M&E)Plate and tube settlers (M&E)Plate and tube settlers (M&E)Plate and tube settlers (M&E)Plate and tube settlers (M&E)Plate and tube settlers (M&E)Plate and tube settlers (M&E)

39



Plate and tube settlers (M&E)Plate and tube settlers (M&E)Plate and tube settlers (M&E)Plate and tube settlers (M&E)Plate and tube settlers (M&E)Plate and tube settlers (M&E)Plate and tube settlers (M&E)Plate and tube settlers (M&E)

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LAYOUT OF TUBE SETTLERS CLARIFIERLAYOUT OF TUBE SETTLERS CLARIFIERLAYOUT OF TUBE SETTLERS CLARIFIERLAYOUT OF TUBE SETTLERS CLARIFIERLAYOUT OF TUBE SETTLERS CLARIFIERLAYOUT OF TUBE SETTLERS CLARIFIERLAYOUT OF TUBE SETTLERS CLARIFIERLAYOUT OF TUBE SETTLERS CLARIFIER

(Gangtok Water Treatment Plant)(Gangtok Water Treatment Plant)(Gangtok Water Treatment Plant)(Gangtok Water Treatment Plant)(Gangtok Water Treatment Plant)(Gangtok Water Treatment Plant)(Gangtok Water Treatment Plant)(Gangtok Water Treatment Plant)

42Source: RN Sharma



TUBE SETTLERSTUBE SETTLERSTUBE SETTLERSTUBE SETTLERSTUBE SETTLERSTUBE SETTLERSTUBE SETTLERSTUBE SETTLERS

43Source: RN Sharma



COLLECTING CHANNEL OF CLARIFIERCOLLECTING CHANNEL OF CLARIFIERCOLLECTING CHANNEL OF CLARIFIERCOLLECTING CHANNEL OF CLARIFIERCOLLECTING CHANNEL OF CLARIFIERCOLLECTING CHANNEL OF CLARIFIERCOLLECTING CHANNEL OF CLARIFIERCOLLECTING CHANNEL OF CLARIFIER

44Source: RN Sharma







Low DO levels, presence of other Low DO levels, presence of other Low DO levels, presence of other Low DO levels, presence of other

gases, precipitation of minerals likegases, precipitation of minerals likegases, precipitation of minerals likegases, precipitation of minerals like

Fe, As, Mn due to oxidationFe, As, Mn due to oxidationFe, As, Mn due to oxidationFe, As, Mn due to oxidation

Hardness removalHardness removalHardness removalHardness removal

Turbidity, TSS, colloid removal, chlorineTurbidity, TSS, colloid removal, chlorineTurbidity, TSS, colloid removal, chlorineTurbidity, TSS, colloid removal, chlorine

to prevent biological growth on filter to prevent biological growth on filter to prevent biological growth on filter to prevent biological growth on filter

mediamediamediamedia

47Sincero and Sincero, 1996Sincero and Sincero, 1996Sincero and Sincero, 1996Sincero and Sincero, 1996

Pathogen removalPathogen removalPathogen removalPathogen removal

HARD GROUNDWATERHARD GROUNDWATERHARD GROUNDWATERHARD GROUNDWATERHARD GROUNDWATERHARD GROUNDWATERHARD GROUNDWATERHARD GROUNDWATER




gggg

Turbidity, colloid removalTurbidity, colloid removalTurbidity, colloid removalTurbidity, colloid removal

Turbidity, TSS, floc removalTurbidity, TSS, floc removalTurbidity, TSS, floc removalTurbidity, TSS, floc removal

Turbidity, TSS removalTurbidity, TSS removalTurbidity, TSS removalTurbidity, TSS removal

48Sincero and Sincero, 1996Sincero and Sincero, 1996Sincero and Sincero, 1996Sincero and Sincero, 1996


TURBID SURFACEWATERTURBID SURFACEWATERTURBID SURFACEWATERTURBID SURFACEWATERTURBID SURFACEWATERTURBID SURFACEWATERTURBID SURFACEWATERTURBID SURFACEWATER

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Ch4 Water Treatment II Coag