Feedstock : Naphtha / LNG / C2- C3 to light olefins to polymersPOLY OLEFINS*

WHY POLYMERS ?Polymers ensued a new era to the society. Polymers are the materials of choice due to their versatility viz: Physical and Chemical strengths, Lightness in weight, Chemical and Corrosion resistance, Attractiveness, Easy processability, Durability in all whether conditions and finally Economic viability.. *

Global Polymer Demand (2005-2020)

. 2005 2013 2020

Polymer 170 220 270 MMT

PE 60 80 90 PP 50 70 80PVC 30 30 40PS 10 20 30*

Categarization of polymersPlastics: Formed by application of pressure and heat. Possess plasticity, rigidity, high mechanical strength, abrasive resistance, dimensional stability ,extensibility. Elastomers: High polymers with elastic properties, low modulus and molecular cohesion

Fibres : Knitted or woven into dimensionally stable garments with high modulus and extensibility Coatings : polymers having low modulus and adhesion properties. high chemical inertness and impermeability towards water, solution and gases.*

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Plastics: PE, PVC, PS, PP, Polycarbonate, Poly methyl methacrylate, Urea and Melamine formaldehyde, Polyurethene, Fluorocarbon.

Elastomers: SBR, PBR, Neoprene.

Fibers: Nylons, Polyesters, Acrylic, Methacrylic poly olefins, Fluorocarbons, PP, Vinyls.

Coatings: Epoxies, Silicones, Polyamide

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Classification of polymerStereo polymers are further sub-devided into Atactic, Isotactic and Syndiotactic polymers*

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Olefins Olefins serve as basic feed stock for many chemicals, intermediates etc. which are used in production of polymers, fibers, rubbers, pharmaceuticals, dyes, pesticides etc. Ethylene and Propylene are the most important light olefins. These are the building blocks for the chemical industry.*

Naphtha CrackerNaphtha cracker remains the fundamental unit of the global petrochemical industry producing olefins namely ethylene, propylene, butadiene and pyrolysis gasoline.Various technologies for steam cracking across the world.1 M W Kellog 2 Stone& Webster3 ABB Lummus4 Technil KTJ5 Linde AG*

Naphtha Cracker Unit Process technology :

Cracker comprises of pyrolysis section, hot fractionation, compression, refrigeration, drying, cold separation and storage.*

DetailsPyrolysis heater : consists of convection zone and radiation zones where naphtha is pyrolytically cracked at 820c to give a mixture of olefins..Hot fractionation : Quenching and heavies separation.Compression section: cracked gases at 30c are compressed in a 5 stage centrifugal compressor to a pressure of 40 kg/cmg. Drying : the gas is then made free of moisture by means of molecular sieve*

Cold separation: The gases are liquefied to sub zero temperatures -165 c by means of propylene and ethylene refrigeration systems. The cold liquid then is separated in various fractionation columns viz de-methanizer, de-ethanizer, ethylene fractionator, de-propanizer, propylene fractionator and de-butanizer.Storage : ethylene propylene and other separated liquids are storedeither in refrigerated atmospheric tanks or Horton spheres under pressure*

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Offsite & storage Storage : ethylene, propylene and other products are stored either in refrigerated atmospheric tanks are in Horton spheres under pressure*

Purity of c, c & c for polymers productionPropylene: propylene 99.5 mole% propane 0.4 mole% MAPD 5 ppmEthylene: ethylene 99.95 mole% ethane 300 ppmButadiene: butadiene 1:3 99.6 % butadiene 1:2 20 ppm*

PROPERTIES

Mol. Wt. Melting Temp. MFI Particle size distribution Glass transition temp Amorphous density Crystalline density Softening point Izod impact Tensile strength

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PolyethyleneDiscovered in 1935 by Mr.Gibson Demand of LLDPE: higher than LDPE & HDPELLD : largest grade of commodity polymer in IndiaLD+HD+LLD prodn in India in MTARIL(IPCL) 4,20,000 RIL Hazira 4,00,000 Haldia petrochemicals; 3,20,000 IOC panipat : 3,00,000*

CatalystLDPE is prepared at high pres and high temp where as LLD. & HD at low pres and low temps.LD: peroxides HD: Ziegler Natta organometallic catalyst (a complex between al alkyl and transition metal halide such as titanium tetrachloride) LD: Copolymer of ethylene with olefins(c-c)*

Production of LLDPE There are three major types of LOW PRESSURE processes for producing LLDPE / HDPE

Slurry, Solution and Gas phase

1.Slurry process: using an inert diluents in which catalyst is affixed to an inert support. The polymer formed during production remains suspended in the liquid medium which is later separated.

2. Solution process: both catalyst & polymer remain dissolved in a solvent which is subsequently separated and recovered

3.Gas phase : monomer, co-monomer, H2, catalyst in pre-polymer form and inert gas N2 introduced in a fluidized bed type reactor. Gas phase processes have the widest application in terms of melt flow index and densities.*

Limitations of various processesSlurry: Limited to densities > 0.937gm/ cm3and MI up to 10. Bimodal slurry processes have grown due to great demand for pipe and film production.Solution: Wider window in terms of densities and MI Best suited for higher value added products with Octane-1Gas phase: Widest operating window for densities and MI. But encounters difficulties in resins with very low densities due to stickiness and agglomerate formation*

Slurry type

(a) Chevron Phillips 15% hexene, ethylene and supported catalyst are introduced in the reactor & isobutene as diluent. press 37 kg/cmg, temp 100 c

(b) Solvay loop reactor 2% press 30 kg/cmg, temp 80 c *

Phillips slurry loop process*

Solution type: (a) SABIC-Compact hexane as diluent, Ziegler catalyst, ethylene, H2, butene-1 as co-monomer, press 2- 5 kg/cmg, temp 150-200 c MI range 0.1 -100,density 0.9- 0.967,

(b) BASELL Hostalene 3% hexane as diluent, H2, monomer, comonomer and catalyst press 7-10 kg/cmg , temp 75-85 c

(c) Dow 7% ethylene, octane-1, catalyst press 27 kg/cmg temp 160 c

(d) Mitsui 9% uses hexane as diluent, comonomer butane-1 press 7-8 kg/cmg, temp 85 c

(e) Dupont (now with Scaliartech) [NOVA] 5% cyclohexane. reaction time 2 mts*

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Gas phase process1. Union Carbide UNIPOL 29 %2. BP Amaco (Innovene) 10 %3. Basell (Technimont) spherilene 2 % Low capital & operating costs. Grade change over with minimum off grade production. Wide range of MI . Significant reduction in reactor purges. Easy reactor operation, grade changes on mathematicalmodel and Interchangeability of production lines of LLDPE/ HDPELow inventory in the process. Low pressure & low temperature process than conventional high pressure .

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Gas phase fluidized bed reactor The reactor is a vertical type one. operating pressure 20 kg/cmg and 70c. N, ethylene, butene and H are circulated in loop using a cycle gas compressor. Catalyst is made in-situ and grown to a bigger particle size by ethylene in a pre-poly reactor separately to reduce the activity of Ti, improve particle-size distribution and introduced into the reactor. Polymer powder is continuously withdrawn from the reactor and separated in a degasser. The gas is recycled back to reactor and polymer extruded out in pellet form for storage into silos *

LLDPE Reactor Fluidised bed*

Development in catalyst for ldpe/hdpe/lldpe1.oxygen & peroxide 2 chromium 3. ziegler 4.supported catalyst for gas phase 5.metallocene 6.transition metal single site *

Extrusion/ blending& transportation- powder silos- extrusion- sieving- transportation- storage and blending- off grade silos & recycling- packing*

colouring & compounding

- master batch preparation- extrusion to colour pelleting - packaging*

Safety criteria in design

-site & layout :- fire protection: -OSBL , -ISBL,-building & structures-process equipment and pipingflare systemdrainageemergency shut down systemsmisc: safety showers, hot surfaces, noise levels ,escape provision

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-Polymerisation: fire hydrant, sprinkler, flare, s/v, rov, co system, TEAL area, Plant emergency shut down system: cw ,power I.air, steam failure, external fire, -sensors and alarms. Pelletising section: dust explosion relief, -Bagging area: fork lifts, trucks movement-Monomer storage area: drainage, dykes, ROV,-Chemical storage and handling area*

LLDPE / HDPE share by capacity & process*

Capabilities of different processes per Density & Melt Index*

Additives used in polymersBroad classification: (1) processing: stabilizers, slip agents, lubricants, accelerators, nucleating agents, impact modifiers, heat stabilizers.(2) functional: fillers, colorants, flame retardants, antistatic agents, antioxidants, antimicrobials. Market is dominated by plasticizers and flame retardants*

Additive- commercial name Manufacturing stage (u/s & d/s of extrusion) 1. Anti oxidants- Irgonox 2. Lubricants: - Calcium stearate, zinc stearate 3.UV stabilizers 4. Antiblock agents: (silicons) - Gasil 5. Slip agents: (olemides) - Erucylamide 6. To prevent discoloration( thioesters) - DSTDP*

Polymer properties / ApplicationsInjection moulding: Mw/Mn

Plastics & usesPE LDPE Free radical initiate film sheet, house ware, pipe, toys HDPE Ziegler natta film sheet, house ware, pipe, toys, containers LLDPE Ziegler natta HMWHDPE Ziegler nattaPP Homo Ziegler natta Fibre products, automobile parts, tyres, appliance parts, Random Ziegler natta toys house warePVC Free radical initiationwires cables, insulation, ,sheets adhesives, automobile parts, coatings, pipe fittingsP V A Free radical emulsion, paints, adhesivesP S GP Free radical packing, disposable containers, HI appliance parts Expanded packing *

plastics & uses- contd Poly isobutylene cationic chain lubricating oils, poly acrylonitrile (AF) free radical fibres in apperal, house ware Polyamide (Nylon 6) bulk oriented fibre, heavy cast parts, fabrics ,fishing line, furniture Poly urethene poly conden rubber, foam, coatings

ABS free radical automobile aplliances, camera bodies, telephone partsStyrene acrylonitrile (SAN ) free radical electric equipment, house ware

PMM free radical fixtures, aircraft windshield, cock pit cover , lenses poly carbonate poly conden aircraft parts, CD, helmets, beverage trans esterifi dispencersMelamine formald- step conden dinnerware, table top ehydeurea formaldehyde poly conden particle wood binder, paper, textile *

Thank you Many other polymers viz. epoxy resins, PBR, SBR, PET, polyester, PTFE, acrylic fibres, fluoro plastics etc. are yet to be covered

There is no failure except in no longer trying*

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