Training Module DM Plant

WELCOME

In its pure state :• Colourless

• Odourless

• Tasteless liquid

• Good solvent

Water

.

Barely 0.1% of

the total volume of water on the earth is

available as fresh water.

Water

.

The consumption of water for domestic , industrial & agriculture total 1000 m3 per person per year with a great disparity between the developing countries & the

advanced nations.

Water

Sources of water Ground Water

Surface water(Rivers,Ponds & Reservoirs etc)

Sea Water

• It may be free as when directly fed through seepage from run off.

• The water is characterized by a weak turbidity, a constant temperature, chemical composition & a near absence of oxygen.

• It is often very pure microbiology.

• It contains notable iron, manganese, hydrogen sulphide & fluoride.

• This refers to all water on the surface of the ground both flowing & stored.

• It can be found stored naturally as in lakes or artificially in storage reservoirs.

Characteristics:

• Presence of dissolved gased specially oxygen.

• Heavy concentration of suspected soilds in flowing water.

• Presence of natural organic matter resulting decomposition of vegetable or animal organism.

• Daily & seasonal fluctuation of temerature ,oxygen, iron,manganese.

This is third option of natural water in the sea flowing on the surface of the earth.

Characteristics:

• Strong salinity ranges from 17 g/l to 270 g/l in the dead sea.

Parameter Surface Water

Ground Water

Sea Water

Temperature Variable Constant Variable

Suspended Solids

Low – High Absent Low – High

Turbidity Low – High Very Low Low

Organic Matter

Low – High Very Low Low – High

Dissolved Oxygen

Near Saturation

Nearly Absent Near Saturation

Salinity Low – Medium

Medium - High

Very High

Impurities in Water • Undissolved & suspended soilds

materials.

Impurities in Water • Dissolved salts & minerals.

Impurities in Water Dissolved gases

Impurities in Water Other materials (as oil,Acid) either

in mixed or unmixed forms.

Undissolved & suspended soilds materials

• Turbidity & Sediments• Sodium & Potassium salts• Iron• Chlorides• Maganese• Silica• Microbilogical Growth• Colour

.

Dissolved salts & minerals:

Calcium & Magnesium salts present

in the form of sulphates ,chlorides

Carbonates & biocarbonates.

Impurities in Water

.

Dissolved Gases

• Oxygen

• Carbon Dioxide

Impurities in Water

Impurities in Water

Other Materials:

• Free Mineral Acid e.g sulphuric or

hydrochloric acid.

• Oil / Grease

Colour : Colour may be due to some mineral impurities. Iron & manganese colour the water as they precipitate when water is brought into contact with air.

True colour after filtration is due to presence of dissolved or organic matter. There is no relationship between colour & quantity of organic matter.

TURBIDITY Turbidity is a description of how clear

water is, or in other words, the clarity

of the Water. In simple terms it is a

measurement of the water’s

"muddiness" or “cloudiness”.

TURBIDITY

In more precise terms, it is an expression of the optical properties of water that cause light to be scattered and absorbed in the water. Increased Turbidity changes the direction of the light, rather than letting it be transmitted through the water in a straight line down to the waterbed.

Total Suspended SoildsDifference between Turbidity and Total

Suspended Solids (TSS) :Despite the fact that total suspended solids or TSS affect Turbidity, Turbidity is not the same as TSS. TSS is a measurement of the dry weightmass of non-dissolved solids which are suspended in the water.

Total Suspended SoildsDifference between Turbidity and Total

Suspended Solids (TSS) :They are measured as the solids suspended per unit volume of water and expressed as mg/l. Bothorganic (like algae, zooplankton and detritus) and inorganic (like clay, silt and sand) solids are included in TSS.

TSS & TurbidityDifference between Turbidity and Total

Suspended Solids (TSS): Turbidity refers to the optical properties of water.Turbidity is not a measurement of the concentration of suspended sediments. Turbidity is not only affected by TSS, but also by the shape of particles, size distribution, refractiveindex , color and absorption spectra.

Turbidity Turbidity is measured by a

nephelometer in Nephelometric Turbidity Units or NTUs. The nephelometer measures the clarity of the water and NTUs represent the average volume of particles scattered over a defined angular range. Both particle size and concentration of suspended solids as well as dissolved solids can affect this reading.

TURBIDITY

If Turbidity is low, light will continue in the same direction. If Turbidity is high, light will scatter, illuminating the particles in the water, much like a ray of sunlight illuminates specks of dust in the air. The general rule is: the cloudier the water, the greater the Turbidity.

Equipment Details

Construction of vessel

Equipment Details Ejectors use a high pressure fluid to compress

low pressure fluid to an intermediate pressure.

Equipment Details.Ball Valve & Butterfly

valve

Equipment Details Diaphragm Valve

Raw (River) water Quality

• pH 7-8

• Turbidity NTU 10-70

• Suspended solids mg/l 3-20

• Oil / Grease mg/l 0-0.5

• Total hardness as CaCO3 mg/l 30-80

• Particle Size mm < 0.10 

Raw (River) water Quality

• Iron Fe total mg/l 0-0.5

• Manganses(Mn) mg/l NT

• Chlorides(Cl) mg/l 5-15

• Sulphates (SO4) mg/l 1-4

• Silicate(Sio2) mg/l 8-20

• Total dissolved mg/l 70-150  solids

Coagulant Dosing Tank

Hypo Dosing Tank

Dual Media Filter

Activated carbon Filter

UV System

DM Plant

Soft Water

Raw Water Reservoir

Other Utilities

Drinking water

Sedimentation Tank

Ion Exchanger

Boiler & Other Utilities

COAGULANT DOSING TANKCOAGULANT DOSING TANK

Coagulation is the process where by finely divided particles of turbidity & colour which are capable of remaining in suspension indefinitely are combined by chemical means into the masses sufficientlarge sizes to effect rapid settling. .

HYPO DOSING TANKHYPO DOSING TANK

Remove Micro-biological & bacteria by use of Sodium hypo chloride (NaoCl) chemical.

Cont..

DUAL MEDIA FILTERDUAL MEDIA FILTER

In order to remove the suspended impurities.

ACTIVATED CARBON FILTERACTIVATED CARBON FILTER

For reduction of colour,odour organics matter and other impurities.

Cont..

SEDIMENTATION TANKSEDIMENTATION TANK

Provide the retention time for the floc particles to settle & drain out.

UV SYSTEMUV SYSTEM

For final disinfection by eliminating micro bacteria.

UV Radiation

Exposure to Ultra Violet radiation can therefore be used to remove bacteria & viruses with out

additions of chemicals.

O3 +hv O*+ O2

O*+ H2O 2 OH˙

UV Radiation

• Its great advantage is that not introducing foreign substances to the Water.

• Ultraviolet radiation is produced by high Pressure or low Pressure Mercury vapor lamps.

• The low pressure lamps emit lowered power radiation but are more energy efficient & longer lasting than high pressure lamps.

ION EXCHANGER ION EXCHANGER

To remove ions ,which are positively charged e.g. calcium & magenesium ions.

• The processes of ion Exchange is accomplished by ion exchange Resin.

• The present day resin is an inert , insoluble polymer, which has exchangeable ions.

1) Cation Exchange Resin.2) Anion Exchange Resin.

• Cation Exchange Resin are used in the sodium (Na+) & Hydrogen (H+) forms.• Anion Exchange Resin are used in the Hydroxide (OH˙) or free base forms.

Cation Exchange Resin consist of

• SAC – Strong Acid Cation.

• WAC – Weak Acid Cation.

Anion Exchange Resin consist of

• SBA – Strong Base Anion

• WBA – Weak Base Anion

• Mix base anion resin

• In this process hard water is converted into soft

water. Thus the Calcium & Magnesium ion responsible for the hardness in the incoming water, are replaced

by the less harmful & acceptable sodium ion thereby

making water soft.

Cont..

Reactions:

Ca(HCO3)2 (l) + 2 Na R(S) Ca R2(S) + 2 NaHCo3 (l)

MgCl2 (l) + 2 Na R (S) Mg R2 (S) + 2NaCl (l) Hard Water Regenerated Exhausted Soft Resin Resin Water

Cont..

Regeneration :

Ca R2 (S) + 2Nacl (l) 2NaR(s) + Cacl2(l)Exhausted Regenerant Regenerated Waste EffluentResin Resin

MgR2 (s) + 2Nacl (l) 2Na R (S) + Mgcl 2 (l) Exhausted Regenerant Regenerated Waste Effluent Resin Resin

Cont..

Regeneration steps in sequence :

1)Back wash

2)Injection of sodium chloride solution.

1)Rinse

Regeneration steps in sequence :

1)Back wash: During backwash a reverse flow of water is maintained.

• Water enters the unit from the bottom, fluidises the resin & is then led to drain.

• Lower the pressure drop.

Regeneration steps in sequence :

2) Injection of sodium chloride solution:The

designed quantity of sodium chloride solution

is brought into contact with the resin to

convert the exhausted resin to the operating sodium form.

Regeneration steps in sequence :

2) Injection of sodium chloride solution:

The sodium chloride solution is injected • At a concentration of 10-15% .

• Within a particular range of flow rates .

• For a predetermined time.

Regeneration steps in sequence :

3) Rinse: In this step the excess regenerant is washed off the resin before the resin is taken for the next service cycle.

Activated Carbon Filter

Strong Acid Cation

Weak Base Anion

Degasser

CO2

Strong Base AnionMixed Bed

Filter Water

DM Water

ACTIVATED CARBON FILTERACTIVATED CARBON FILTER

To remove excess free chlorine,colour,organic matter and other impurities.Since chlorine is poisonous to the SAC resin, which will deactivate its physical strength, it is to be removed

STRONG ACID CATION (SAC)STRONG ACID CATION (SAC)

To remove cation (positive ion) such as Ca,Mg,Na Sodium being a monovalent It leaches first. Maximum Na slip 0.2 ppm.

Cont..

Reactions:

MgSO4 + 2RH R2 Mg + H2SO4

Cacl2 + 2RH R2Ca + 2HCL

Nacl + RH RNa + HCL

Cont..

Regeneration : Regeneration done by 30% HCL diluted Through ejector to 5% conc.

RNa + HCl RH + Nacl

R2Mg + 2HCl 2RH + Mgcl2

R2Ca + 2HCL 2RH + Cacl2

Regeneration is re-conversion of resin into operating form. Hardness should be nil.

Cont..

WEAK BASE ANION (WBA)WEAK BASE ANION (WBA)

To remove chloride & organic matter.

HCl + R R-HCl

Regeneration : By NaoH via strong Base Anion exchanger through fare regeneration.

RHCL + NaOH RNacl +H2O

Cont..

DEGASSERDEGASSER

Degasser is polypropylene rings packed column.Countercurrent flow of water with Air,by running Air blower, Carbonic Acid is

split into to CO2 & H2O.

H2CO3 H2O + CO2

Cont..

STRONG BASE ANION (SBA)STRONG BASE ANION (SBA)

To Remove all Acid of Strong nature such as HCL and Sulphuric acids and weak bases such as carbonic acids.

SBA Regeneration: RCl + NaOH ROH + NaCl R2SO4 + 2 NaOH 2ROH + Na2SO4

R2SiO3 + 2NaOH 2ROH + Na2SiO3

Cont..

MIXED BEDMIXED BED

To remove the final traces of cations & anions in order to produce Ultra pure quality.

Quality Check : pH,Conductivity, and Sio2

DM Water Quality• pH 6.8-7.2

• Turbidity NTU <1

• Suspended solids mg/l <1

• Oil / Grease mg/l 0-0.5

• Total hardness as CaCO3 mg/l <0.10

• Conductivity µS/cm <0.15

DM Water Quality• Iron Fe total mg/l N.T

• Manganses(Mn) mg/l N.T

• Chlorides (Cl) mg/l Nil

• Silicate(Sio2) mg/l < 0.02

• Total dissolved mg/l < 1.00   solids