conditions of material recycling and material LCA reflecting closed-loop recycling Steel as an eco-friendly material

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1 EMECR2017 conditions of material recycling and material LCA reflecting closed-loop recycling Steel as an eco-friendly material Oct. 12, 2017 Toru Ono Nippon Steel & Sumitomo Metal Corporation 1

2 Table of Contents 1. Importance of life cycle thinking 2. Advantages of steel in material recycling 3. worldsteel LCA methodology for steel products reflecting scrap recycling 2

3 1. Importance of Life Cycle Thinking 3

4 What are eco-friendly materials? natural materials? recycled materials? carbon free materials? Life Cycle Thinking is important! A Case Study on Automobile Eco-friendly paper car? very 4

5 Tailpipe Emission Regulation How to get it? Weight reduction is one of solutions. 5

6 Challenging weight reduction with HSS 60 Tailpipe 70 Emission Regulation soft steel regular HSS <440MPa HSS <590MPa Super HSS >1180MPa, hot-stamping HSS - Super HSS MPa Theoretical strength of iron is 12GPa. We have commercially reached 1-1.5GPa in flat products and 4-4.5GPa in wire products. Parts Required Performance Tensile stiffness Anti-dent Stiffness Endurance Dynamic crush strength strength outer door outer inner structure floor front rail rear pillar front side member side sill door guard cover suspension arm under floor wheel disk dominant factor except for thickness Young's Yield strength Young's Strength Strength modulus modulus 6

7 kg-co CO 2 emission from material production stage Per 100kg Normal steel 100kg eq. HSS:75kg Aluminum:67kg Magnesium:50kg CFRP:45kg Reference :World Auto Steel Normal steel HSS aluminum magnesium CFRP 7

8 Environmental burden Life Cycle Thinking Highlighted stage Hidden stage Hidden stage burden in production stage burden in use stage burden for waste treatment, recycling effects Evaluating only a partial stage (e.g. use stage) of the entire life cycle may lead us to a misleading result total burden throughout the entire life cycle Importance of Life Cycle Thinking 8

9 Life Cycle CO2 Emission Comparison among types of vehicle Material selection becomes more important Fuel economy is dominant Material selection is dominant Driving stage Fuel preparation Material, body and parts production waste treating/recycling EEA Signals 2017 Conventional Diesel EV Future trend 9

10 2. Advantages of steel in material recycling STEEL 10

11 Automobile Production in the World automobile production (million) area EU Japan USA China world area Over 90 million cars are produced disposed in the world every year What are the conditions for eco-material for mass production products? JAMA mass productivity, economy and technical performances are essential, in addition to those, recyclability is the key 11

12 Types of Material Recycling Product End of Life Direct disposal Thermal recycling Natural resources substitution Material production process Final product production process Closed-loop recycling Use in society Cascade recycling Thermal Recycling (Open-loop Recycling) EoL products are incinerated and the heat is recovered as thermal energy to produce electricity or steam. The recovery has no effect on the reduction of natural resource consumption for virgin materials, but it is a low cost and energy saving way for recycling of flammable materials. Cascade Recycling (Open-loop Recycling) The material is used as a secondary material in another product. The recycle may continue cascadely in several steps. In each step, the material quality drops or changes and finally the material comes to the EoL. Closed-loop Recycling The material is recycled to the original material without or with very little loss of its characteristics or quality so that the number of recycling can be infinite. Closed-loop recycling reduces consumption of natural resources of the material, accompanying environmental impacts, and generation of wastes. Closed-loop recycling is superior to open-loop recycling in terms of sustainability. Material EoL STEEL 12

13 Life Cycle of Steel Products Steel keeps its metalic state even after the EoL of products Steel is still Steel! Fe2O3 Fe Steel Steel Natural resources Steel Steel production process Steel products Final product production process Final products End of life of final product Steel Scrap substitute Steel can be recycled however many times into whatever steel product you want Sustainable & Flexible Life Cycle 13

14 % Characteristics of Steel: Characteristics of Aluminum: Conditions for Quality drop by recycling Microstructure Alloying Control Autonomous/Sustainable Al 20 not removable Heating Finishing elements) Roughing (Tramp Online cooling process Hot reveler casting process V furnace mill mill 18 B 16 Aluminum has a lotzrof 14 removable by gasification tramp elements; Ti 12 hence it is very Cr Temp. 10 berolling change Zn Strengthening by combination difficult of coolingto and 8 recycled Steel has a limited Mg finishing roughing 6 number of tramp heating while keeping cooling Mn 4 elements; hence original quality. Cu 2 steel can be easily Microstructure Fe 0 changerecycled while Si 1080 original N01 keeping Intermediate cooling Rapid cooling Slow cooling Grain growth control Re-crystallization elongation Pure Al Al-Cu Al-Mn Al-Si Al-Mg Al-Mg-Si Al-Zn-Mg quality MPa Over 800MPa MPa Material Recycling a) Separation and collection is easy b) Environmental impact of recycling is smaller compared to production using natural resources c) Recycling system is economically sustainable Additional conditions for Closed-loop Recycling aluminum foil tank screw, gear, can body piston, cylinder automotive, rivet, head, panel wheel, shaping mold can end マルテンサイト 硬い組織 オーステナイト鋼を利用したTRIP鋼 car body, appliance, sash, axle airplane, railway car d) No/small quality degradation through recycling Variety of characteristics of steel products are realized by microstructure control removable by slaging through rolling and cooling in the process. DP鋼の複合組織 Aluminum realizes its functions by alloying. Each alloy series must be recycled in the same alloy system (same product like Can to Can). Mixture of several kinds of aluminum scrap can be used Hiraki et al. only casted aluminum or die-cast Thefor microstructure is reset by melting and reconstructed for new product. 10μm e) Can be recycled into various products 20μm オーステナイト 力が加わる 変 STEEL & SUMITOMO METAL CORPORATION All Rights Reserved NIPPON STEEL & SUMITOMO METAL CORPORATION All Rights Reserved. EMECR NIPPON NIPPON STEEL & SUMITOMO METAL CORPORATION All Rights Reserved

15 LCI for steel products 3. worldsteel LCA methodology for steel products reflecting scrap recycling 18

16 Lifelong Environmental Burden of Steel with eternal recycling Lifelong production Lifelong burden Lifelong unit burden = Xpr + rxre + r 2 Xre + r 3 Xre + + r n-1 Xre 1 + r + r 2 + r r n-1 When infinite recycling ( n ), then r n 0 1 r n 1 =Xpr + r (Xre Xpr) Substitute r = , Xpr = 100, Xre = 25 Environmental burden =39.25 =1 + r + r 2 + r r n-1 =Xpr + rxre + r 2 Xre + + r n-1 Xre A Amato, L Brimacombe, N Howard. (1996) Ironmaking and Steelmaking, Vol23, No. 3, Average lifetime of steel (2005 stock base) * *Ichiro Daigo, Materials Science and Technology of Japan, Vol.54(2), (2017) r :scrap recovery rate yield Xpr :burden for primary production Xre :burden for recycling =(Xpr Xre) (1-r) (1-r n ) + Xre Number of life cycle (= 1+recycled number) Natural resources Xpr rxre r 2 Xre r 3 Xre 1 r r 2 r 3 use use use use 19

17 LCA methodology reflecting scrap recycling - worldsteel-lca methodology - It evaluates both BF-BOF and EAF as one whole steel cycle system. Through scrap recycling, the natural resource consumption and related environmental impacts can be avoided (environmental value of scrap) Same as the economic value of scrap, the environmental value of scrap is credited for its recovery and burdened for its use natural resource substitution B1: Burden for scrap use Environmental value A: Steel production process BF BOF EAF Scrap End of life of products B2: Credit for scrap recovery Cradle to No grave A: Process burden Scrap recycling effect B1: Burden for scrap use B2: Credit for scrap recovery Total burden 20

18 Evaluation of Scrap Recycling Effect assuming the burden to produce a unit of steel product only from natural resources is 100 (Xpr), the burden to produce a unit of steel product only from scrap is 25 (Xre), and yield of steel product from scrap is 0.9, then environmental value of scrap = (100-25) x 0.9 = 67.5 The environmental value of scrap is credited when it is recovered and burdened when it is used. for example, when the recovery rate of scrap is 0.9, then credit for scrap recovery equals to 67.5 x 0.9 = And when the yield is 0.9, then burden for scrap use equals to 67.5/0.9 = 75 Scrap recycling effects 21

19 100% virgin route 100 A case study Scrap recycling effect % scrap route Xpr Xre process burden 0 burden for scrap use credit for scrap recovery Process burden of 100% virgin root: Xpr = 100 Process burden of 100% scrap root : Xre = 25 Scrap environmental value = (100-25) x 0.9 = 67.5 where yield of steel product from scrap =0.9 Burden for scrap use in 100% virgin root: Burden for scrap use in 100% scrap root : 67.5/0.9 = 75 where yield of steel products from scrap = 0.9 Credit for scrap recovery = 67.5x0.9 = where scrap recovery rate = 0.9 total burden There is no difference between 100% natural resource route and 100% scrap route if scrap recycling effects are correctly reflected. 22

20 ISO Development of worldsteel-lca Methodology ISO 20915: LCI calculation methodology for steel products 2017 NIPPON STEEL & SUMITOMO 2017 NIPPON METAL STEEL CORPORATION & SUMITOMO METAL All Rights CORPORATION Reserved. All EMECR2017 Rights Reserved. 23

21 worldsteel-lci data collection Access the most comprehensive and reliable steel life cycle inventory data today: 24

22 Conclusions 1. Life Cycle Thinking is the key to keep right direction in global environmental issues 2. Steel has great advantages in terms of material recycling 3. worldsteel LCA methodology gives a clear answer for steel LCA reflecting closed-loop scrap recycling 25

23 Thank you for your attention 26