PolyPropylene stereoregular, crystalline polymer

Transcription

1 PP Technology

2 Content Introducing PP Application History Ziegler-Natta polymerization Catalyst development PP processes Process control Process safety Key equipment Investment cost Cost of production 2

3 Introducing PP PolyPropylene stereoregular, crystalline polymer Homopolymers Random copolymers with 0,5-4% ethylene content Impact (block, heterophasic) copolymers with 5-20 % ethylene content Terpolymers - with second comonomer Characteristics Melt index 0,3->100 g/10 min (230 C/2,16 kg) Melting point C Polydispersity (TVK grades) 3,5 5 reactor products 2 3 controlled rheology (CR) products Broad range of mechanical properties 3

4 Application 1,0 7,6 3,0 PP end-use 19,4 film fibre blow moulding injection moulding extrusion coating other extrusion 39,6 27,8 others 1,6 4

5 FILM Application by Properties HECO RANDOM SHEET INJECTION MOULDING HOMO PIPE FIBER FIBER melt blown 0, MI, g/10 min/230 C 5

6 History Discovered by Giulio Natta and Karl Rehn in 1954 First industrial process developed by Montecatini in 1957 Catalyst is the driver for process and product development Licences available for 400 kt/y capacity single lines Consumption in 2012 Global: 52 million t Domestic: 157 thousand t TVK PP plants kt/y Hercules slurry process, shut down in kt/y Sumitomo bulk process, shut down in kt/y Spheripol process, debottlenecked to 100 kt/y kt/y Spheripol process, debottlenecked to 182 kt/y 6

7 Ziegler-Natta Polymerization 1 Ziegler - Natta catalyst preparation Propylene polymerization 1. Base support MgCl2 1. ZN catalyst 2. Titanation TiCl4 Internal donor 2. Activation Al-alkyl External donor (e.g. silane) (e.g. phtalate) 3. Polymerization Propylene 3. ZN catalyst 4. PP product 7

8 Ziegler-Natta Polymerization 2 8

9 Catalyst Development Generation (year) Catalyst composition Productivity (kg PP/g cat) X.I. (%) Remarks 1st (1954) δ-ticl 3* 0,33AlCl 3 + AlEt 2 Cl No morphological control, deashing and atactic removal necessary 2nd (1970) δ-ticl 3 + AlEt 2 Cl Granular catalyst, deashing necessary (1968) MgCl 2 /TiCl 4 + AlR 3 40 First MgCl 2 based catalyst for PE, very low stereocontrol 3rd (1971) 4th (1980) 5th (1988) MgCl 2 /TiCl 4 /Benzoate + AlR 3 /Benzoate MgCl 2 /TiCl 4 /Phtalate + AlR 3 /Silane MgCl 2 /TiCl 4 /Diether + AlR 3 /Silane (opt.) First MgCl 2 based catalyst for PP, low stereocontrol, low H 2 response, broad MWD Spherical catalyst with controlled porosity, medium-high stereocontrol, medium H 2 response, medium MWD Same as 4th generation but very high activity, narrow MWD, excellent H 2 response 6th (1999) MgCl 2 /TiCl 4 /Succinate + AlR 3 /Silane Same as 4th generation but broad MWD 9

10 PP Processes First PP process: slurry phase technology in stirred tank reactors; numerous process steps necessary Deashing to remove catalyst residues Atactic PP removal Up-to-date processes: few process steps only Bulk or gas phase polymerization Catalyst residues and atactic PP removal not necessary 10

11 PP production simplified block diagram Polymerization of homopolymer/random copolymer Polymer and monomer separation Polymer separation and cleaning Additivation and pelletizing Raw material preparation and treating Polymerization of block copolymer 11

12 Slurry Technology Early PP Process Not used today 12

13 Spheripol Process Typical process parameters Process step Temperature, C Pressure, bar Catalyst activation Prepolymerization Polymerization - loop reactor High pressure separation Polymerization - gas phase reactor Steaming 105 0,2 Drying 90 0,1 13

14 Spheripol Process Polymerization Catalyst Donor Precontacting HP Flash Separator Copoly Reactor TEAL Loop Reactor Prepoly Reactor S Flash Line Slurry Pump SC Hydrogen Propylene Recovery and Purification Gas blower Ethylene Hydrogen Propylene LP Separator S Steamer Nitrogen Dryer PP Powder to Extrusion 14

15 Spheripol Process Additivation and Pelletizing 15

16 Unipol Process Polymerization C 25 bar 16

17 Unipol Process Degassing and Recovery 17

18 Chisso Process Packed Gas Phase Reactors 18

19 Spherizone Process 19

20 Spherizone Process Multizone Reactor Principle 20

21 Spherizone Process Extended Product Properties Broad MWD 35 Pressure pipe classification PP-R 125 Maximum stiffness Homopolymer 2550 MPa flexural modulus Random Minimum brittle -3 C transition temperature 2,3 Narrow MWD Impact-Stiffness balance HECO: 5 KJ/m2 Izod 1650 MPa flexural modulus Spherizone Spheripol Gas phase 21

22 Process control Melt index Isotactic index (stereoregularity) MWD Raco ethylene content Heco ethylene content H 2 concentration in reactors external donor (alkyl/donor ratio) different H 2 concentration in reactors, catalyst ethylene feed residence time, C 2 /C 3 ratio in GP reactor 22

23 Bipolymer C2 content, % Bipolymer CXS, % Block copolymer C2 content vs gas composition CXS(BIP) C2(BIP) ,35 0,37 0,39 0,41 0,43 0,45 0,47 0,49 C2/(C2+C3) m ol ratio 23

24 Process Safety Risk of high volume liquid hydrocarbon Interlock system Emergency kill to prevent reaction runaway Action valves automatically operated by predefined process parameters to separate/blow-down equipment Closed blow-down system Pressure safety valves, blow-down valves release to closed system, connected to Flare to burn blown hydrocarbon Double mechanical seal on pumps in liquid propylene service Gas detectors Fire fighting system 24

25 Key Equipment Reactors Loop with axial circulating pump Gas phase Gas circulating blower/compressor Extrusion line 25

26 Gas Circulating Blower 26

27 Investment cost Basis: WE 2010 Q1 PP HOMO PP HECO Process Bulk Bulk+gas phase Capacity 325 kt 325 kt Investment, million EUR ISBL OSBL Total investment Specific investment cost, EUR/t

28 Cost of Production Basis: WE 2010 Q1; 325 kt PP HOMO PP HECO Process Bulk Bulk+gas phase Capacity 325 kt 325 kt Propylene 865,8 796 Comonomer 80 Catalysts&chemicals 24,9 24,9 Total raw materials 890,7 900,9 Power 24,1 26,3 Other utilities 15,9 15,9 Total utilities 40 42,2 100% 90% 80% 70% 60% 50% Total fixed costs Total utilities Total raw materials Direct fix costs 17,1 17,1 Allocated fix costs 13,6 13,6 Total fixed costs 30,7 30,7 Total cash costs 961,4 973,8 40% 30% Bulk Bulk+gas phase 28

29 Appendix: BOPP Film Production Stenter Process 29

30 Appendix: Injection Moulding 30