INTRODUCTION TO CHLOR ALKALI PLANTBy: C.S.Babu AVP (CA)

ContentsOverview of Chlor Alkali Industry in IndiaIntroduction of Chlor Alkali Plant (RIL(DMD))Process DescriptionProcess Control

OVERVIEW OF CHLOR ALKALI INDUSTRY IN INDIA

Overview of Chlor Alkali Industry in India

Total Chlor Alkali Plants in india 34Total Production Capacity 29.11 Lacs MTPA as on 31.03.2008

Ref: AMAI

Major Chlor Alkali Plants in IndiaReliance Industries Ltd, DahejG A C L, (Vadodara, Dahej)GRASIM, NagdaDCM (Kota, Jhagadia)UPL Unit -5, JhagadiaIndian Rayon, VeeravalPunjab Alkalies & Chemicals Limited, NangalChemfab Alkalies, PondicheriTATA Chemicals Ltd, Mithapur

Types of Manufacturing Process

Membrane Cell ProcessMercury Cell ProcessDiaphragm Cell ProcessOtherDirect oxidation of HCl with Oxygen or Air

INTRODUCTION OF CHLOR ALKALI PLANT RIL(DMD)

Chlor Alkali Plant (CA)Date of Commissioning 31st March, 1997 Designed CapacityCaustic 133600 MTAChlorine 118500 MTA

Capacity ExpansionCaustic 165600 MTAChlorine 140000 MTADate of Capacity Expansion 10th Nov 2004

Process Licensor: UHDE, GmbhEngg. Contractor: Uhde India Limited

Caustic Concentration Unit (CCU)Process Licensor: BertramsEngg. Contractor : Kilburn engg.Designed Capacity:Caustic Flakes: 150MT/DayCaustic Prills : 150 MT/DayDate of Commissioning: 31st August,1998

Major Equipments in the PlantElectrolysersChlorine, Hydrogen & Air CompressorRectiformersRefrigeration units ( Ammonia Compression & VAR)Centrifuges, clarifier, filtersCaustic Evaporation Unit (CEU)Caustic Concentration Unit (CCU)Prilling tower

Awards Won

Fourth place in Green Rating of Caustic Chlorine Industry by CSE.

Major Records AchievedDaily:494 MT

Monthly:15170 MT

Yearly:164524 MT

ManpowerTotal :130Supervisory:50Non supervisory:80Process:70Maintenance:60

PROCESS DESCRIPTION

Major Products & ByproductsProductsCaustic ChlorineBy ProductsHydrogen30 %HClSodium HypochloriteSpent Acid

Feed Stock Option & SourcingMajor raw material is industrial grade salt.It is sourced from salt suppliers from the local areas such as GandharDahejJambusarNadaBhavnagar

UTILITIESCooling Water Chilled waterDM WaterFilter WaterMP SteamLP SteamLP Condensate Plant AirInstrument AirNitrogenPower

Chemical ConsumptionBarium CarbonateSodium CarbonateSodium HydroxideSodium By SulphiteAlfa CelluloseFlocculentSugar25 % HCl98 % Sulphuric Acid

Process Overview

Primary & Secondary Brine UnitSalt Handling & StorageBrine Saturation Brine PrecipitationBrine ClarificationBrine FiltrationBrine PolishingSecondary Brine PurificationPure Brine Heat ConditioningChlorate Destruction UnitAnolyte Dechlorination Catholyte Section

Cell HouseElectrolysersSeries of Cell ElementsCathode PanAnode PanMembraneElectrolyser Work Shop

Chlorine SystemChlorine CoolingChlorine DryingChlorine CompressionChlorine LiquefactionChlorine EvaporationChlorine Storage

Hydrogen SystemHydrogen CoolingHydrogen StorageHydrogen Compression

Caustic Evaporation & Concentration UnitMultiple Effect EvaporationCaustic ConcentrationCaustic FlakingCaustic Prilling

Other UnitsHCl Synthesis UnitWaste Air dechlorination UnitVapour Absorption Refrigeration UnitAmmonia Compression Refrigeration System

PROCESS CONTROL

Advance Process Control FeaturesDCS by Tata Honeywell, TDC 3000PC-PLC by Tata HoneywellSiemens PLC for burnerSiemens PLC for chlorine compressorAllen Bradley PLC for Rectiformers

ENERGY CONSERVATION

Energy Conservation FeaturesMembrane cell technologyHeat recovery interchangersVARCaptive use of HydrogenPartial bypassing of chlorine liquefier

ENVIRONMENT MANAGEMENT

Environmental Consideration WAD is designed to take care of 10 minutes of total chlorine production.Extra dump tank 18% Caustic in WAD section HCl vent gases are treated with 18% caustic..O2 analyser in molten salt furnace stack.Operating philosophy is to keep minimum Cl2 inventory. only i.e. Approximately 50 MT.SLF for solid waste.Neutralizations and circulation facilities in effluent pit. Two PH analysers are also present.Chlorine Detectors

Wastes Management

SAFETY

Potential Chemical HazardsIn CA Plant we handle Hazardous Chemicals as listed below.Caustic (32%,48%,98.5% solid)Chlorine98% Sulphuric Acid78% Sulphuric Acid30% HCLAmmoniaSodium HypochloriteHot Brine

Potential Fire HazardsHydrogenAmmoniaMolten SaltDowtherm OilLubrication oils and DieselPlastic PipingElectric Short Circuit

Process Safety ConsiderationTrips / Interlocks by DCS for process plant.HCl furnace interlocks are hardwired.Cl2 compressor interlocks are hardwired.N2 purging in molten salt furnace stack.N2 purging in HCl furnace - after tripping.

Process Safety ConsiderationProcess design for safe startup, operation and S/D.Remote Control operation for chlorine supply to VCM.Specific measures taken to avoid explosion in cell house between hydrogen & chlorine.On line analyser provided for hydrogen in chlorine sniff gas.N2 purging system whenever electrolyser is cutout. implemented for avoiding popping. This was based on M/s UHDE recommendation.

Process Safety ConsiderationFire water network provided in the entire plant.Fire and smoke detection alarm system.Cl2 detectors in plant area (26 nos).H2 detectors in cell house, H2 area.Safety showers provided at various locations.Breathing air line provided in critical Cl2 areas.Cl2 safety valve vents connected to WAD

Mechanical Safety ConsiderationSuitable MOC used for corrosive services:Cell house : Pans - Titanium /Nickel Suitable plastic metallurgy for wet chlorine / caustic services.For dry chlorine service - LTCS/ Carbon steel.PVC - FRP piping for H2SO4 service.PVDF for chlorate destruction.Ti/Ni / Haste alloy-C for exchanger.Safety valves with rupture disc with failure indication in DCS in chlorine service after compressor.Pumps are double mechanical seal in caustic ,Hypo and H2SO4 service.

Safety Consideration for Chlorine Handling & Storage5 bullets with always one bullet kept as spare.Alternate measuring devices for level.Automatic closure of liquid chlorine inlet at high level.Remote operated on/off valves.Bellow seal valves in chlorine service.Double safety valves along with rupture disks to prevent high pressure.

Safety Consideration for Waste Air Dechlorination UnitThree stage scrubbing.Dumping of caustic from overhead tank incase of fast temperature increase.Dosing based on redox.UPSV to prevent higher vacuum.Remote operated auto standby system.Emergency power supply includes DG set.

COST ECONOMICS

Cost of Production

SALES & DISTRIBUTION

Sales & Distribution

End Users Viscose Manufacture Pulp and paper industriesSoaps and detergentsChemical industryNitrite and Nitrate ManufactureAlumina IndustryRIL market share is 10%.

Thank you

Introduction to Chlor Alkali PLantIntroduction to Chlor Alkali PLant