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vBrine saturation process.

vPurification process.

v

Cell House-Electrolytic process.

Caustic Soda Manufacture.

By

NarendraPrasath R,

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Precipitation tank:Precipitation is done by adding 10% NaOH

,

10% MgSO4, 10% Ba2CO 3 in the tank.Flocculant agents like magna floc are added toform flocwhich is removed. This is sent to the

Clarifier.

From saturation tank.To clarifier

precipitation

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Clarifier : The brine isconcentrated by using a centrifugal pump andthe principle of sedimentation.

Over Flow.

Fromppt

Clarifier

Forpurificatio

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Purification is done by anthracite and by ion-exchange method.

Anthracite filters use porous anthracite coalarranged in beds. Cleaning is done bybackflushing.

Ion exchangers have -cellulose tightly packedin tubular sieves. They absorb finner particlesand produce ULTRA PURE BRINE(99.9%) whichis sent to the cell house for electrolysis.

PurificationPurification

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Anthracite Ion

ULTRA PURE BRINE

Purification ProcessPurification Process

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vUltra pure brine is electrolysed.vThe lye produced is collected and sent to triple

effect evaporator, for further concentration.

vThe concentrated lye is filled in drums.

vTo form flakes, the lye is sent to the furnace

which is maintained at 450C by burningnitrates. The water is evaporated and then it iscut by rotating blades.

Electrolytic Process.

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Electrolytic Cell Process

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Used as base in chemical industries, Labs fortitraion purposes.

High demand in soap manufacturing industrieslike Hindustan Lever ltd.

Used in hair straightening process, performedby professionals.

In paper industry, forms the main componentof white liquor, bleaching agent of brown pulp,to maintain the pH > 10.5.

And many more

Uses of Caustic Soda

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The major product is Cautic soda or Lye.Lean brine is sent for recycle, after removing

Cl2.

Hydrogen produced is completely burned withchlorine gas to produce HCl, used in industries.Chlorine is also separately filled in drums and

sold.

The sludge produced is dried, powdered andused as Nfhyk; powder.

Usage of the by products

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The major raw material is only salt, directlyproduced from salt pans.(Very low cost)

Major product is lye, the by-products likehydrogen and chlorine is used for HCl

production and certain amount of Hydrogen isused for burning process instead ofcoal.(Energy utilization)

The ultimate waste is only the sludge and the

flue gases sent out after reused for heatingpurposes.

The by-prods are of high commercial demand,

Highlight of this plant

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Eye glass: The reaction of lye and moisture isexothermic, and can cause blindness if comesin eye contact.

Helmet: To avoid impacts on the skull.Gloves: Handling flakes can cause burns

without rubber gloves over the hand.

Safety and Hazards

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The cost of each membrane used is in lakhs, sothe total cost of membranes reaches crores.

The maintanence of membrane is veryimportant since any chlorine ion reaching the

other electrode causes short circuit.Hence high initial and maintainance cost.Coastal area for easy availability of salt and

water. And need for ports to transport, exportthrough ships and tankers.

Need for large area.

Disadvantages

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THE ENDThanks for your presence!