Pitfalls in Recycling of Ferrous Metals · 13 Iron and steel shearing and slitting 14 Forged...

Pitfalls in Recycling of Ferrous

Metals

Prof. Dr. Shinichiro Nakamura

Waseda University, Graduate School of Economics, Tokyo 169-8050

Ecotopia Science Institute, Nagoya University, Nagoya 464-8603

30. October 2011 1 Forum on sustainable resource management of metals, Taipei

Recycling is a major component in closing

the cycle between industrial products and

the environment

• End-of-Life legislation is designed to accomplish this

purpose and set targets for the recycling rate of

discarded products.

• The EU legislation, for example, requires 85% of cars to

be recycled (Directive, 2000/53/EC of the European Parliament

and the council of 18 September 2000 on end of life vehicles.).

Amini et al. J. of Cleaner Production 15, 907-913 (2007)

30. October 2011 Forum on sustainable resource management of metals, Taipei 2

However…

• Recycling can create streams with a lower quality which

are un-economical to recycle partially due to the

limitations of thermodynamics, which makes refining

difficult.

Amini et al. J. of Cleaner Production 15, 907-913

(2007)

• Mixing (incomplete separation) of metal species in the

EoL phase that cannot be properly accommodated by

current metallurgical processes that are optimized for

processing natural ores


Sr

Ta

Nb V

Ag

Sn

Cr Zr

B

U Mn

Cu

Si

Co Ni W

Mo

Ti Fe

Pb

Zn

Mg Ca

La Ce Al

Fe (BOF,EAF)

Bi

Hg

Mg

Te Cd

Pb Zn

Au

Pt Rh Pd

Ag

Sn

Al

Cr

Ga Ge

In

Mn

Se

Cu

Re

Ni

B

Sb

Fe

Sr

W

Cu (Converter)

Au

Pt

Ir Ta

W

Mo

Nb Zr Y

U Ce

V B Co Ni

Pd Fe Ti

Gd

Ho Si Dy Cr

Ge Cu

Sn Mn As

Ag Ga

Sb In

Bi Pb

Li Sr

Hg

Cd

Zn

Mg

Ca Al

Be

Yb

La

Al (Remelting)

Au

Pt

Pd

Ag

Sn

Bi

Hg

Al

Cr

Ga In Mn Mg

Cu

Ni

W

Fe

Pb

Zn

Zn&Pb (ISP)

Au

Pt

Pd

Ag Sn Bi

Hg

Al

Cr Ga

In

Mn

Mg

Cu Ni W Fe

Pb

Zn

Pb (Blast furnace)

Ca Al

Zr

Mn

Bi

Si

Ni

Ge

La Ce

Zn Sr

Na Mg

Li

Fe

Sn

Cu

Sb

Ag

Y Gd

Yb

Hg

Tl

Pu to Metal phase

to Slag phase

to Gas phase

Elements that have distributed

among the metal phase as a

solid or liquid metal

Elements that have distributed

among the slag phase as oxide

Elements that have evaporated

and distributed among the gas

phase.

Recoverable element

(as pure metal)

Alloying element

Deoxidation agents

Mg (Remelting)

4

Nakajima et al. ES&T (2011)

Quality losses of metals in recycling:

literature review

• Recycling of End of Life Vehicles (ELV): – Castro, Remmerswaal, Brezel, Reuter: Res. Cons. Rec. 52, 2007

– Amini, Remmerswaal, Castro, Reuter: JOCP. 15, 2007

• Cu in Iron & Steel (I&S) scrap – Igarashi, Daigo, Matsuno, Adachi: ISIJ Int. 47, 2007

• Losses of alloying elements in recycling (refining

processes): – Nakajima, Yokoyama, Matsuno, Nagasaka, ISIJ Int. 47, 2007

– Nakajima, Takeda, Miki, Matsubae, Nakamura, Nagasaka, ES&T 44,

2011

– Hiraki, Takeda, Nakajima, Matsubae, Nakamura, Nagasaka, Science &

. Tech. Adv. Materials. 12, 2011


Purpose

• Quality issues of I&S scrap from ELVs

• Quantifying the losses: Castro et al/Amini et al 2007

– Material losses

– Quality losses

– Dilution losses

• Hybrid approach at high level of resolution

– Nakamura/Yamasue: ES&T 44, 2010: dilution of scrap in EAF

– Nakamura/Nakajima: Mater. Trans 46, 2005: WIO-MFA

– Eight I&S scrap categories distinguished by origins: Matsubae

et. al ISIJ Int. 51, 2011

– Separation/liberation of 25 parts/components from ELV: Tasaki

2003

30. October 2011 6

Forum on sustainable resource management of metals, Taipei

Origin of I&S scrap 2005: Matsubae et. al. ISIJ Int. 51, 2011

30. October 2011 7

103 kg


0 5,000,000 10,000,000 15,000,000 20,000,000 25,000,000

Other steel scrap

Pressed scrap

Shredded scrap

Heavy scrap

Stainless steel scrap

Industrial steel scrap

In-house steel scrap

Pig iron scrap

Production process

End of life

0 5000000 10000000 15000000 20000000

Other steel scrap

Pressed scrap

Shredded scrap

Heavy scrap

Stainless steel scrap

Industrial steel scrap

In-house steel scrap

Pig iron scrap

Crude ordinary steel (BOF) Crude special steel (BOF)Crude ordinary steel (EAF) Crude special steel (EAF)Cast materials (iron) Forged materials (iron)

Use of I&S scrap in steel production


103 kg

Old scrap

New scrap

Direct use of ferrous materials

0% 20% 40% 60% 80% 100%

Pig iron

New scrap

Old scrap

Crude ordinary steel (BOF) Crude ordinary steel (EAF)Crude special steel (BOF) Crude special steel (EAF)Cast materials (iron) Forged materials (iron)


Final destination of ferrous materials


• Where do ferrous materials go?

• In which “final products” are ferrous materials

embedded?

• Trace the flow of ferrous materials along the supply

chain downward from basic materials toward final

products: trace the material flow following the stage of

fabrication.

30. October 2011 Forum on sustainable resource management

of metals, Taipei

11

Triangulation of an IO matrix: Trace the flow of materials along fabrication stages

Resources

: Metal ores

Materials: Metals

Products: Automobiles

Final

demand

Resources

Materials

Products

Triangularity

FeAl Cu Zn

PbFerroalloys

Motor carsConstruction

Metal products

Machinery

Iron oreCoal

WIO-MFA: Nakamura and Nakajima; Mater. Trans. (2005),

Nakamura, Nakajima, Kondo, Nagasaka; JIE (2007)


WIO-MFA:

C: material composition matrix

M measured in kg => C in kg as well



Metal & plastic composition of products

0.000

0.200

0.400

0.600

0.800

1.000

Ordinary steel shapes

Ordinary steel sheets and plates

Cast and forged m

aterials (iron)

Electric w

ires and cables

Rolled and draw

n copper andcopper alloys

Rolled and draw

n aluminum

Non-ferro

us metal castings and

forgings

Optical fiber cables

Passenger m

otor cars

Motor vehicle parts and

accessories

Residential construction

(wooden)

Residential construction (non-

wooden)

Products

1000

kg

Pig iron Ferroalloy Copper Lead

Zinc Aluminum Thermo-setting resins The polyethylene (low density)

Polyethylene (high density) Polystyrene Polypropylene Vinyl-chloride resins

High-performance resins Other resins Iron scrap Copper scrap

Lead scrap Zinc scrap Aluminum scrap Plastic scrap

Testing WIO-MFA


70% 75% 80% 85% 90% 95% 100%

JAMA1997

JAMA2001

WIO-MFA

Composition in the metal and plastics mass of a passenger car

Iron Copper Lead Zinc Aluminum PVC Other Plastics

Ferrous materials constituting a car

• Car consists of many parts/components

• The material composition of a car is determined by the

material composition of its parts/components

• I&S scrap embedded in a car

– Nakamura, Kondo, Matsubae, Nakajima, Nagasaka: UPIOM: A

New Tool of MFA and Its Application to the Flow of Iron and

Steel Associated with Car Production, ES&T 45, 2010


5 10 15 20 25 30

1 Passenger motor cars 2 Motor vehicle bodies 3 Electric audio equipment 4 Motor vehicle parts and accessories 5 Internal combustion engines for motor vehicles and parts 6 Electrical equipment for internal combustion engines 7 Electric lighting fixtures and apparatus 8 Bearings 9 Plumber's supplies, powder metallurgy products and tools10 Other metal products11 Metal containers, fabricated plate and sheet metal12 Bolts, nuts, rivets and springs13 Iron and steel shearing and slitting14 Forged materials (iron)15 Cast materials (iron)16 Other iron or steel products17 Forged steel18 Steel pipes and tubes (ordinary steel)19 Steel pipes and tubes (special steel)20 Coated steel21 Hot-rolled special steel22 Ordinary steel sheets and plates23 Ordinary steel strip24 Ordinary steel bar25 Ordinary section steel26 Other hot-rolled ordinary steel27 Cold-finished steel (special steel)28 Cold-finished steel (ordinary steel)29 Crude steel (EAF) special steel30 Crude steel (BOF) special steel31 Crude steel (EAF) ordinary steel32 Crude steel (BOF) ordinary steel33 Pig iron

0

5

10

15

20

25

30

35

40

45

50

IO flow of Primary Iron induced by a car

30. October 2011 17

Nakamura et. al.: UPIOM: A New Tool of MFA and Its Application to

the Flow of Iron and Steel Associated with Car Production, ES&T 45, 2010 Forum on sustainable resource management of metals, Taipei

Representation of UPIOM by Sankey diagram

(a composite of the two Figures)

2011/6/07 Shinichiro Nakamura, Waseda University 18

EoL processes of ELV


Disassembled for reuse

Disassembled for recycle Shredded for recycle

Three types of losses: Amini/Castro et. al. (2007)

1. Material losses:

– Shredder/slag losses

2. Quality losses:

– No equal quality to primary iron due to mixing

3. Dilution losses:

– Dilution by primary iron required in EAF due to high

concentration of contaminants (Cu).


Quantifying the losses: WIO

Quality losses Dilution losses

Description I&S scrap not used in BOF but

in EAF

I&S scrap diluted with primary

iron to meet the target quality

of EAF; Cu < 0.003%

Scenario settings EoL process recovers primary

iron

The primary iron/scrap ratio

increases in EAF

Nakamura and Yamasue

ES&T 44, 2010


Modeling based on WIO: S. Nakamura and E. Yamasue ES&T 44, 2010


The demand for EAF in the functional unit

• Production of a car makes little use of EAF steel => closed

loop recycling of I&S scrap not possible=>system expansion

• For recycling to occur, the functional unit must include the

demand for EAF steel as well.

• If dilution is required, the demand for EAF steel must include

the diluted portion as well.

• Comparison of alternative scenarios under the same

functional unit calls for the same amount of demand for EAF

steel for the case of both with and without dilution.


Scrap quality, dilution, and demand for EAF steel S. Nakamura and E. Yamasue ES&T 44, 2010


Avoiding mixing. How?

• Classify scrap types based on chemical composition

• Design for disassembly (DfD): joints/liberation of

materials ADF

• “Smart” sorting processes


Thank you for your

attention

For further inquiry or questions, please visit

www.f.waseda.jp/nakashin/

30. October 2011 26


Pitfalls in Recycling of Ferrous Metals · 13 Iron and steel shearing and slitting 14 Forged...

Documents

Transcript of Pitfalls in Recycling of Ferrous Metals · 13 Iron and steel shearing and slitting 14 Forged...