Exergy II T. Gutowski 2.83 and 2.813 READINGS: Gutowski, T.G., et - - PowerPoint PPT Presentation

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Exergy II T. Gutowski 2.83 and 2.813 READINGS: Gutowski, T.G., et al., Thermodynamic Analysis of Resources Used in Manufacturing Processes, Evniron. Sci. Technol., 2009, 43 (5). Gutowski, T.G., Materials Separation and Recycling Chapter for

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2

Exergy II

  • T. Gutowski

2.83 and 2.813

READINGS: Gutowski, T.G., et al., Thermodynamic Analysis of Resources Used in Manufacturing Processes, Evniron. Sci. Technol., 2009, 43 (5). Gutowski, T.G., Materials Separation and Recycling Chapter for Thermodynamics and the Destruction of Resources, B.R.Bakshi, T.G.Gutowski, and D.P.Sekulic, Camb. U. Press.

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3

Exergy Accounting

  • The Good:
  • Rigorous framework
  • Focus on system definition
  • Aggregate fuel and non-fuel materials,

heat and work interactions

  • Analysis tool
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4

Exergy Accounting

  • The Not So Good:
  • Any aggregation scheme is subject to

trade-offs

  • For fuels, many of the same answers can

be obtained from LHV

  • It is not a well known term
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SLIDE 4

5

Aggregation (Valuation) Schemes are needed, but…

  • Price
  • Weight
  • Lower Heating Value
  • “Energy Equivalent”
  • Exergy
  • Others…
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SLIDE 5

6

Today: Applications

  • Cumulative exergy accounting

– Fuels, ηII , EROI – Manufacturing processes, ηII & Actual MJ/kg

  • Minimum work of separation

– Exergy of a mixture

  • Economic Analogies

– Mining and extraction – Recycling

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SLIDE 6

7

General Framework

& BW ,in & BW ,out & BQ,in & BQ,out & Bloss & Bout & Bin

Data requirements: stoichiometrically balance reaction equation,or an inventory of inputs and outputs

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SLIDE 7

8

Cumulative Exergy Accounting

& BW ,in & BW ,out & BQ,in & BQ,out & Bloss & Bout & Bin & BW ,in

& BW ,out & BQ,in & BQ,out & Bloss & Bout & Bin

& BW ,in & BW ,out & BQ,in & BQ,out & Bloss & Bout & Bin

Energy Conversion Process Materials Production Process Manufacturing Process

EXERGY LCA

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SLIDE 8

9

Exergy Homework

  • 9. What is the maximum work one could
  • btain from burning the following fuels

with oxygen: octane? methane? methanol? hydrogen? How much CO2 is generated for each?

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SLIDE 9

10

Burning Octane

2C8H18(l) + 25 O2(g)  16 CO2(g) + 18H2O(g)

2(5413.1) + 25(3.97) - 16(19.87) - 18(9.5) = ΔB ΔB = 10,436.53 kJ 10,436.53 = 45.8 MJ 2[(8 x 12) + 18]= 228g kg

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11

Exergy Value of Fuels

& Bin + & BW ,in + & BQ,in = & Bout + & BW ,out + & BQ,out + & Bloss & BW ,in & BW ,out & BQ,in & BQ,out & Bloss & Bout & Bin

Octane, Oxygen Carbon Dioxide, Water Vapor Useful Effect

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12

Gasoline Production

& Bin + & BW ,in + & BQ,in = & Bout + & BW ,out + & BQ,out + & Bloss & BW ,in & BW ,out & BQ,in & BQ,out & Bloss & Bout & Bin

Fractional distillation and catalytic cracking require energy, (exergy), say α x100% LHV or Exergy for production Crude Oil Energy Inputs Gasoline, other By-products Heat Out

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13

How to estimate α?

  • If this is an established technology you

can look up the research results

  • If this is a new technology you will need a

model or an analogy

  • In this case gasoline production has been

going on for some time. Values of α vary depending upon the the nature of the crude oil and the technology, but α ≈0.15

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14

Cumulative exergy accounting

& Bin + & BW ,in + & BQ,in = & Bout + & BW ,out + & BQ,out + & Bloss

& BW ,in & BW ,out & BQ,in & BQ,out & Bloss & Bout & Bin

Examples: energy to produce Gasoline, Ethanol, Hydrogen etc

& BW ,in & BW ,out & BQ,in & BQ,out & Bloss & Bout & Bin

& Bin + & BW ,in + & BQ,in = & Bout + & BW ,out + & BQ,out + & Bloss

Fuel Production Energy Production

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15

Alternative Points of View

  • exergy out/exergy in
  • Second law efficiency
  • Roughly,
  • 1/1.15 = 0.87
  • You always lose

something!

  • energy out/energy in
  • Energy return on

energy investment

  • EROI 1/0.15 = 6.7

A gift from nature

(Assume α = 0.15)

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16

EROI Accounting

& Bin + & BW ,in + & BQ,in = & Bout + & BW ,out + & BQ,out + & Bloss

& BW ,in & BW ,out & BQ,in & BQ,out & Bloss & Bout & Bin

Examples: energy to produce Gasoline, Ethanol, Hydrogen etc

& BW ,in & BW ,out & BQ,in & BQ,out & Bloss & Bout & Bin

& Bin + & BW ,in + & BQ,in = & Bout + & BW ,out + & BQ,out + & Bloss

Fuel Production Energy Production

X

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17

Exergy Accounting

& Bin + & BW ,in + & BQ,in = & Bout + & BW ,out + & BQ,out + & Bloss

& BW ,in & BW ,out & BQ,in & BQ,out & Bloss & Bout & Bin

Examples: energy to produce Gasoline, Ethanol, Hydrogen etc

& BW ,in & BW ,out & BQ,in & BQ,out & Bloss & Bout & Bin

& Bin + & BW ,in + & BQ,in = & Bout + & BW ,out + & BQ,out + & Bloss

Fuel Production Energy Production

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18

Burning Methane

CH4 + 2O2  CO2 + 2H2O

ΔB = 831.7 + 2(3.97) – 19.87 – 2(9.5) = 784.84 kJ 784.9kJ = 49 MJ 12 + 4 = 16 Kg

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SLIDE 18

19

Burning Methanol

O H CO O OH CH

2 2 2 3

2 2 3 +

  • +

kJ B 6 . 685 ) 5 . 9 ( 2 9 . 19 ) 97 . 3 ( 2 3 5 . 718 =

  • +

=

  • kg

MJ kJ 4 . 21 16 4 12 6 . 685 = + +

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20

Burning Hydrogen 2H2(g) + 02(g) 2H20(g)

ΔB = 2 X 236.1 + 3.97 - 2 x 9.5; ΔB = 457kJ Maximum exergy out= 457.17kJ = 114 MJ 4g kg

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21

Calculated Exergy and Reported Heating Values

Smil 42-44 Fuel oil 75 42 Oil Methanol Hydrogen Methane Octane Carbon Chemical 21 114 49 46 33 Calculated Max Exergy MJ/kg* 64 56 68 112 CO2 generated gCO2/MJ

  • Nat. gas

Gasoline Coal anthracite Fuel 114 33-37 38-50 46-47 18-29 30-33 Heat of Combustion MJ/kg Smil Smil Web Smil Smil BCCA Ref

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22

Making Hydrogen

2H2(g) + 02(g) ← 2H20(l)

ΔB = 2 X 236.1 + 3.97 - 2 x 0.9; ΔB = -475kJ Minimum work required = 475kJ = 119 MJ 4g kg The minimum work to produce the hydrogen is larger than the maximum work obtainable from combustion!

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23

How could hydrogen work?

From an energy point of view, you From an energy point of view, you could produce H2 from wind, or PV. could produce H2 from wind, or PV. This still This still leaves a number of issues: leaves a number of issues: Infrastructure development, Infrastructure development, Storage, and Safety lead the list. Storage, and Safety lead the list.

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SLIDE 23

24

Hydrogen is an energy Carrier Not an energy source

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SLIDE 24

25

EROI data

Cutler Cleveland, Energy, 2006

Depends on “Quality” of Resource and Technology

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SLIDE 25

26

From Hau and Bakshi es&t 2004

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SLIDE 26

27

Exergy equivalents, deWulf et al ES&T 08

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SLIDE 27

28

Manufacturing Systems as open thermodynamic systems

Mfg Systems

Gutowski et al ES&T 2009

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SLIDE 28

29

Balances for Mfg Process

MF i i

  • ut

i MF i i in i MF

M N M N dt dm

  • =

=

  • =

1 , 1 ,

) ( ) ( & &

res MF prod MF mat MF MF ECMF MF MF ECMF i MF

H H H W Q Q dt dE & & & & & &

  • +

+

  • =
  • MF

irr res MF prod MF mat MF MF i MF ECMF i MF

S S S S T Q T Q dt dS

,

& & & & & & +

  • +
  • =
  • Mass

Energy Entropy

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SLIDE 29

30

Work Rate for Mfg Process in Steady State

& WECMF

MF = (( &

H MF

prod + &

H MF

res ) &

H MF

mat )

T0(( & SMF

prod + &

SMF

res ) &

SMF

mat )

  • 1 T0

Ti

  • i>0
  • &

QECMF

MF + T0 &

Sirr,MF

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SLIDE 30

31

Exergy and Work

  • S

T H S T H B ) ( ) (

  • =

& WECMF

MF = (( &

BMF

prod + &

BMF

res ) &

BMF

mat )

  • 1 T0

Ti

  • i>0
  • &

QECMF

MF + T0 &

Sirr,MF

Branham et al IEEE ISEE 2008

Examples: plastic work, melting, vaporizing etc.

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SLIDE 31

32

Work Rate for Mfg Process

MF irr MF ECMF i i mat MF i n i ch i res MF i n i ch i prod MF i n i ch i ph mat MF res MF prod MF MF ECMF

S T Q T T N b N b N b B B B W

, 1 1 1

1 ) ( ) ( ) ( ) ) (( & & & & & & & & & +

  • +

+

  • +

=

  • >

= = =

  • Here all chemical exergy terms (bch) are at T
  • , Po

Branham et al IEEE ISEE 2008

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SLIDE 32

33

Second Law Eff i ciency; Degree of Perfection

in

  • utput

useful p

B B =

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SLIDE 33

34

Batch Induction Melter Inputs and Outputs

Ductile Iron – Batch Electric Induction Exergy Analysis

Ductile Iron Melt 1000 kg Slag 40 kg Metallic Input Materials and Alloys 1024 kg Input Electricity 5,393 MJ

Boundaries are drawn around the entire facility so that all components are at standard pressure and temperature

Dust 0.26 kg Natural Gas Preheater 0.025 kg

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35

Batch Induction Melter Exergy Analysis*

Material Amount (kg) Weight Percent Standard Chemical Exergy (MJ/kg) Exergy (MJ) Percent Total Exergy

Steel Scrap 439 42.85% 6.89 3022.25 15.39% Pig Iron 1.6 0.16% 8.18 13.43 0.07% Ductile Iron Remelt 535 52.25% 8.44 4513.98 22.99% 65% Silicon Carbide Briquettes 4.3 0.42% 31.73 137.62 0.70% 75% Ferrosilicon 3.0 0.29% 24.51 72.46 0.37% 5% MgFeSi 14.8 1.44% 19.09 282.30 1.44% Copper 1.7 0.17% 2.11 3.69 0.02% Tin 0.005 0.00% 1.13 0.01 0.00% 62% Fe-Molybdenum 6.2 0.61% 7.28 45.35 0.23% Carbon 9012 18 1.80% 34.16 628.45 3.20% Natural Gas Preheater 0.02 0.00% 51.84 1.27 0.01% Electricity 5418.00 55.59% Total Inputs 1024 100.00% 14138.83 100.00% Ductile Iron Melt 1000.2 96.69% 8.44 8436.45 99.29% Slag 33.9 3.28% 1.14 60.05 0.71% Dust 0.3 0.02% 0.26 0.07 0.00% Total Outputs 1034 100.00% 8497 100.00% Mass Difference

  • 1.05%

Ductile Iron Batch Electric Induction Melting

Input Materials Output Materials

*including losses at Utility

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36

Batch Electric Induction Melting

  • f 1 kg of melt

Total Exergy In (Bin) = 11,155,000 J Useful Exergy Out (Bout) = 8,250,000J Component Exergy in (J) Metallics 8,700,000 Electricity* 2,455,000

Batch Electric Degree of Perfection

79 . 000 , 420 , 10 000 , 250 , 8 = = J J

P

  • Degree of Perfection

inputs

  • f

Exergy products useful

  • f

Exergy

P =

  • *not including utility losses
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SLIDE 36

37

Plasma Enhanced Chemical Vapor Deposition (CVD)

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SLIDE 37

38

4849.9 7.028779mol

196.9 N2

99.5 0.008511mol

0.34 Ar

60.79 0.015313mol

0.49 O2

0.749

40928.6 0.029579mol

0.95 SiH4 %Total Inputs Exergy (J) Input moles or primary energy Input mass (g) Species

Input Deposition Gases

36.2

2220000

2220000J

Electricity

Input Energy

266931.6 0.437453mol

31.06 NF3

63.0

3598253 4.326643mol

69.41 CH4

Input Cleaning Gases

3.2667 0.000414mol

0.0248 Undoped Silicate Glass laye

Outputs

Plasma enhanced CVD

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SLIDE 38

39

Data from Sarah Boyd et. al. (2006)

Chemical Vapor Deposition (CVD)

  • f a 600nm

Undoped Silicate Glass (USG) layer at 400°C

Total Exergy In (Bin) = 6,130,000J

Useful Exergy Out (Bout) = 3.3J

7

10 * 33 . 5 123 , 131 , 6 267 . 3

  • =

= J J

P

  • Component

Exergy in (J) Input Gases 45,900 Cleaning Gases 3,865,000 Electricity* 2,220,000 Degree of Perfection

CVD Degree of Perfection

*not including utility losses

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SLIDE 39

40

What is going on here?

  • W/o cleaning gases PECVD ~ 1.4 x 10-6
  • W/o electricity PECVD ~ 8.4 x 10-7
  • Vapor phase processes
  • Slow
  • Small devices
  • Low cost on materials and energy
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SLIDE 40

41

Look at Electricity Only

1. Machining 2. Grinding 3. Casting 4. Injection Molding 5. Abrasive Waterjet 6. EDM 7. Laser DMD 8. CVD 9. Sputtering 10. Thermal Oxidation

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42

Energy Requirements at the Machine Tool

Jog (x/y/z) (6.6%) Machining (65.8%) Computer and Fans (5.9%) Load Constant (run time) (20.2%) Variable (65.8%) Tool Change (3.3%) Spindle (9.9%) Constant (startup) (13.2%) Carousel (0.4%) Unloaded Motors (2.0%) Spindle Key (2.0%) Coolant Pump (2.0%) Servos (1.3%) Jog (x/y/z) (6.6%) Machining (65.8%) Computer and Fans (5.9%) Load Constant (run time) (20.2%) Variable (65.8%) Tool Change (3.3%) Spindle (9.9%) Constant (startup) (13.2%) Carousel (0.4%) Unloaded Motors (2.0%) Spindle Key (2.0%) Coolant Pump (2.0%) Servos (1.3%)

Production Machining Center Automated Milling Machine

From Toyota 1999, and Kordonowy 2002.

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SLIDE 42

43

Electric Energy Intensity for Manufacturing Processes

processed v

  • V

k P P & + =

Power (kW) Process Rate (cm3/sec) physics auxiliary equipment & infrastructure Process Rate (cm3/sec) Specific Energy (MJ/cm3)

V E k V P V P

v

  • =

+ = & &

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SLIDE 43

44

Injection Molding Machines

1 2 3 4 5 6 7 8 50 100 150 200 Throughput (kg/hr) SEC (MJ/kg) HP 25 HP 50 HP 60 HP 75 HP 100 Low Enthalpy - Raise Resin to Inj. Temp - PVC High Enthalpy - Raise Resin to Inj. Temp - HDPE Variable Pump Hydraulic Injection Molding Machines.

Does not account for the electric grid.

Source: [Thiriez ‘06]

m E k m P m P

m

  • =

+ = & &

slide-44
SLIDE 44

45

Thermal Oxidation, SiO2

Ref: Murphy et al es&t 2003

slide-45
SLIDE 45

46

Power Requirements

Ref: Murphy et al es&t 2003

slide-46
SLIDE 46

47

Injection Molding

10.76

  • 71.40

3.76 - 50.45

  • f polymer

processed 1.75E+03

  • 3.41E+03

[Thiriez 2006]

Machining

2.80 - 194.80 0.35 - 20.00

  • f material

remov ed 3.50E+03

  • 1.87E+05

[Dahmus 2004], [Morrow, Qi & Skerlos 2004] & [Time Estimation Booklet 1996]

Finish Machining

  • f material

remov ed [Morrow, Qi & Skerlos 2004] & [Time Estimation Booklet 1996]

CVD

14.78

  • 25.00

6.54E-05

  • 3.24E-03
  • f material

deposited on wafer area 4.63E+06

  • 2.44E+08

[Murphy et al. 2003], [Wolf & Tauber 1986, p.170], [Nov ellus Concept One 1995b] & [Krishnan Communication 2005]

Sputtering

5.04 - 19.50 1.05E-05

  • 6.70E-04
  • f material

deposited on wafer area 7.52E+06

  • 6.45E+08

[Wolf & Tauber 1986] & [Holland Interv iew]

Grinding

7.50 - 0.03 1.66E-02

  • 2.85E-02
  • f material

remov ed 6.92E+04

  • 3.08E+05

[Baniszewski 2005] & [Chryssolouris 1991]

Waterjet

8.16 - 16.00 5.15E-03

  • 8.01E-02
  • f material

remov ed 2.06E+05

  • 3.66E+06

[Kurd 2004]

Wire EDM

6.60 - 14.25 2.23E-03

  • 2.71E-03
  • f material

remov ed 2.44E+06

  • 6.39E+06

[Sodick], [Kalpakjian & Schmid 2001], & [AccuteX 2005]

Drill EDM

  • f material

remov ed [King Edm 2005] & [McGeough, J.A. 1988]

Laser DMD

  • f material

remov ed [Morrow, Qi & Skerlos 2004]

Thermal Oxidation

21.00

  • 48.00

4.36E-07

  • 8.18E-07
  • f material

deposited on wafer area 2.57E+10

  • 1.10E+11

[Murphy et al. 2003] Process Name References Power Required

kW

Electricity Required

J/cm3

9.59 2.05E-03 4.68E+06 Process Rate

cm3/s

2.63 1.70E-07 1.54E+10 80.00 1.28E-03 6.24E+07

slide-47
SLIDE 47

48

In General, over many manufacturing processes,

/sec cm 1 /sec cm 10 Rates Process Material and 50 5 Power Idle

3 3 7

  • V

kW P kW

  • &
slide-48
SLIDE 48

49

1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07 1.E+08 1.E+09 1.E+10 1.E+11 1.E+12 1.E-07 1.E-05 1.E-03 1.E-01 1.E+01 1.E+03 Process Rate [cm 3/s]

Injection Molding Machining Finish Machining CVD Sputtering Grinding Abrasive Waterjet Wire EDM Drill EDM Laser DMD Oxidation Upper Bound Lower Bound

Electricity Requirements [J/cm

3 ]

Specific Energy Requirements J/cm3 for Various Mfg Processes

Gutowski et al IEEE, ISEE 2007

slide-49
SLIDE 49

50

1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07 1.E+08 1.E+09 1.E+10 1.E+11 1.E+12 1.E-07 1.E-05 1.E-03 1.E-01 1.E+01 1.E+03 Process Rate [cm 3/s]

Injection Molding Machining Finish Machining CVD Sputtering Grinding Abrasive Waterjet Wire EDM Drill EDM Laser DMD Oxidation Upper Bound Lower Bound

Electricity Requirements [J/cm

3 ]

Specific Energy Requirements J/cm3 for Various Mfg Processes

Conventional Processes Advanced Processes Micro/Nano

8 orders of magnitude

Gutowski et al IEEE, ISEE 2007

slide-50
SLIDE 50

51

1.E+05 1.E+06 1.E+07 1.E+08 1.E+09 1.E+10 1.E+11 1.E+12 1.E+13 1.E+14 1.E-06 1.E-04 1.E-02 1.E+00 1.E+02 1.E+04

Process Rate [kg/hr]

Injection Molding Machining Finish Machining CVD Sputtering Grinding Abrasive Waterjet Wire EDM Drill EDM Laser DMD Oxidation Melters

Electricity Requirements [J/kg] Gutowski et al IEEE, ISEE 2007

slide-51
SLIDE 51

52

1.E+05 1.E+06 1.E+07 1.E+08 1.E+09 1.E+10 1.E+11 1.E+12 1.E+13 1.E+14 1.E-06 1.E-04 1.E-02 1.E+00 1.E+02 1.E+04

Process Rate [kg/hr]

Injection Molding Machining Finish Machining CVD Sputtering Grinding Abrasive Waterjet Wire EDM Drill EDM Laser DMD Oxidation Melters

Electricity Requirements [J/kg] Gutowski et al IEEE, ISEE 2007

slide-52
SLIDE 52

53

Why are these energy intensities so high?

  • demand for small devices, prices for

energy & materials stable/declining

  • vapor phase processes with slow

deposition rates

  • efficiency used to enhance performance,

not to downsize equipment

  • However, the trajectory of individual

processes is usually toward faster rates and lower energy intensities

slide-53
SLIDE 53

54

Keep in Mind

  • This is intensity not total used
  • This is at the process, not cumulative

exergy!

– loses at energy conversion not included – investment into materials not included – infrastructure not included

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SLIDE 54

55

All Electric Vs Hydraulic Injection Molding Machines

1 2 3 4 5 6 7 8 9 5 10 15 20 Throughput (kg/hr) All-Electric - 85 tons Hydraulic - 85 tons SEC (MJ/kg) Material: PP

Source: [Thiriez 2006]

slide-55
SLIDE 55

56

Work to Separate a Mixture

Pure Component 2 Pure Component 1 Mixture 12

in

W &

  • ut

Q &

  • ut

, i in , i sys , i

N N dt dN & &

  • =

2 1 12

H H H W Q dt dE

in

  • ut

& & & & &

  • +

+

  • =

irr

  • ut

S S S S T Q dt dS & & & & & +

  • +
  • =

2 1 12

irr mix mix in

S T ) s T h ( N W & & &

12

+

  • =
slide-56
SLIDE 56

57

Gibbs Free Energy of Mixing

  • Where Δgmix = Δhmix –T

0 Δsmix

  • and Δhmix = ( h12 – x1h1 –x2 h2),
  • and Δsmix = (s12 –x1s1 – x2s2), and
  • note, x1 and x2 are mole fractions, (N1 / N12

and N2 / N12 respectively), with N12 = N1 + N2.

irr mix in

S T g N W & & &

12

+

  • =
slide-57
SLIDE 57

58

Minimum Work to Separate

mix min min

g N W w

  • =

=

12

& &

Lost Work on Mixing

mix irr

g N S T

  • =

12

& &

slide-58
SLIDE 58

59

Ideal Mixtures

  • for ideal mixtures, Δhmix = 0
  • then, Δgmix = –T0 Δsmix

i n i i

x x R T w ln

1 min

  • =
  • =

i n i i

x N R T W ln

1 min

  • =
  • =
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SLIDE 59

60

Exergy of a mixture

where <

  • +

=

mix mix i pure i i

g g b x b

i i i

  • i

pure i i

x x R T b x b ln

  • +

=

For an ideal mixture,

slide-60
SLIDE 60

61

Two Component Mixture Two Component Mixture

0.2 0.4 0.6 0.8 1 0.2 0.4 0.6 0.8 1

Concentration

H

)) 1 ln( ) 1 ( ln (

min

x x x x R T w

  • +
  • =

1.7 kJ/mole wmin of

separation

Minimum work to separate a mixture

slide-61
SLIDE 61

62

Separation & “Extraction”

slide-62
SLIDE 62

63

Material Extraction

)) 1 ln( ln (

2 1 min

x N x N R T W

  • +
  • =

)) 1 ln( ) 1 ( ln (

min

x x x x R T w

  • +
  • =

)) 1 ln( ln ) 1 ((

2 1 min

x N x N R T W

  • +
  • =

(1) (2) (3) Subtracting (3) from (2) gives the work to separate one mole of mat’l “1”

) 1 (ln

1 min,

x R T w =

slide-63
SLIDE 63

64

Minimum work to separate a component from an constant mixture

) 1 (ln

1 min,

x R T w =

1≤ (1/x) ≤ ∞

1/x ln (1/x)

slide-64
SLIDE 64

65

Example; making pure iron from the crust

Fe (c = 1) 376.4 kJ/mole reduction Fe2O3 (c=1) 16.5 kJ/mole extraction Fe2O3 (c = 1.3 x 10-3) 0 kJ/mole (ground)

slide-65
SLIDE 65

66

Szargut

slide-66
SLIDE 66

67

Extraction from the crust

mole kJ K mole J K B x R T B

  • 5

. 16 10 3 . 1 1 ln 314 . 8 2 . 298 10 3 . 1 1 ln 1 c to (crust) 1.3x10 c from O Fe Extracting

3 3 3 3 2

=

  • =

= = =

  • Note: R = k Navo (Boltzmann’s constant X Avogadro’s number)
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SLIDE 67

68

The Efficiency of Separation

[26] 3.6% (-Δgmix /Q) amine stripping CO2/ combustion gas [15] 0.1% (-Δgmix /Q) Steam vaporization Hexane/ polybutadiene [7] 0.3% (-Δgmix /E) Mining and milling Various metallic

  • res

[3] 2% (-Δgmix /Q) Distillation Propane/ propylene Ref. Efficiency S e p a r a t i o n Process Materials

See Gutowski, Thermodynamics and Recycling, IEEE, ISEE, 2008

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SLIDE 68

69

Economic Analogies with Thermodynamics

  • 1. Extraction
  • 2. Recycling
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SLIDE 69

70

Cost of extraction ~ wmin

) 1 (ln

1 min,

x R T w =

  • Metals mining
  • Biological Materials
  • Pollution Scrubing
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71

From National Research Council, 1987 Separation and Purification: Critical Needs and Opportunities.

effort of isolation market value “leave it in the ground” excellent

  • pportunity

“Sherwood Plot”

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SLIDE 71

72

From Chapman, P.F. and F. Roberts, 1983. Metal Resources and Energy.

Chapman and Roberts, 1983

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73

Figure 1: Sherwood plot showing the relationship between the concentration

  • f a target material in a feed stream and the market value of (or cost to remove)

the target material. From Grübler.

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SLIDE 73

74

Cost of Recycling ~ wmin

20 Product in the US

i n i i

x x R T w ln

1 min

  • =
  • =
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SLIDE 74

75

Shannon Information Shannon Information

0.2 0.4 0.6 0.8 1 0.2 0.4 0.6 0.8 1

Concentration

H

i i

x x k H ln

  • =

Analogy between effort to resolve a coded message and the effort required to separate a complex mixture, See Dahmus and Gutowski, ES & T 2007

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SLIDE 75

76

Product m i k i

($)

H

(bits)

Recycling Rate automobile battery $ 10.95 1.30 96% automobile $ 358.61 2.22 95% catalytic converter $ 107.54 .699 95% refrigerator $ 34.69 1.67 90% newspaper $ .028 .095 70% automobile tire $ 1.85 .575 66% steel can $ .004 .060 63% aluminum can $ .019 .001 45% HDPE bottle (#2) $ .012 .163 27% PET bottle (#1) $ .008 .476 23% paper bag $ .009 .001 21% glass bottle $ .002 .003 20% desktop computer $ 17.69 2.36 11% television $ 7.05 2.09 11% laptop computer $ 2.79 2.89 11% aseptic container $ .005 1.10 6% plastic bag $ .001 .001 5% cell phone $ .908 2.91 1% work chair $ 12.19 2.27 0% fax machine $ 6.43 2.09 0% coffee maker $ .535 1.93 0% cordless screwdriver $ .130 1.80 0% Styrofoam

TM cup

$ .0002 .000 0%

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77

What gets Recycled?

The area of the circles represent the recycling rate, i.e., fraction

  • r end-of-life products that enter the recycling system, autos = 95%

Dahmus and Gutowski, ES & T 2007

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78

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79

Up Next:

  • Monday - Growth and Consequences
  • Wednesday- COAL discussion
  • Following week-Review and Quiz