Transcript Slide 1

Life Cycle Impact Assessment
of flax fibre
for the reinforcement of composites
Nilmini Dissanayake,
John Summerscales, Stephen Grove and Miggy Singh
Content
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Goal and scope
Life Cycle Assessment (LCA)
System boundaries
Life Cycle Inventory Analysis (LCI)
Environmental Impact Classification Factors (EICF)
Methodology
Life Cycle Impact Assessment (LCIA)
Discussion
Conclusion
Future work
Goal and scope
 To determine the sustainability of natural fibres
as reinforcement in polymer matrix composites
(referenced to glass fibres)
 Cradle-to-factory gate
• Agricultural operations (from ploughing to harvest)
• Fibre extraction operations (retting and decortication)
• Fibre preparation operations (hackling and carding)
• Fibre processing operations (spinning or finishing)
 The functional unit : “one tonne of flax fibres
for reinforcement in polymer matrix composites”
(assumes Ef=42 GPa  equal specific modulus)
Flax
• flax fibre chosen as it is the most
agro-chemical intensive bast fibre
used as reinforcement
• other bast fibres could be “greener”
provided yield/hectare and
performance are satisfactory
Life Cycle Assessment (LCA)
Goal and
Scope
Definition
Inventory
Analysis
Impact
Assessment
Interpretation
System Boundaries
Seed, Fertiliser,
Pesticides, Diesel
Machinery
Diesel, Machinery,
Water
Electricity
Crop Production
Dry, green flax stems
Water Retting
Dry, retted flax
Scutching
Scutched long fibre
Electricity
Hackling
SLIVER
Electricity,
Water
Wet Spinning
YARN
Atmospheric Emissions
Emissions into water
Co-products and waste
Life Cycle Inventory Analysis (LCI)
INPUTS
Materials
Value (per tonne of yarn)
Seed
Fertilisers: Lime
Ammonium nitrate
Triple superphosphate
Potassium chloride
Pesticides
Diesel
Electricity
497 kg
2445 kg
445 kg
238 kg
368 kg
9 kg
9 GJ
36 GJ
OUTPUTS
Yarn
Co-products : Short Fibres
Shive
Dust
Coarse plant residues
Direct Emissions : CO2
NOx
SO2
NH3
Particulate matter (PM)
1000 kg
4497 kg
7104 kg
2824 kg
2304 kg
5682 kg
9 kg
0.004 kg
0.062 kg
0.3 kg
Environmental Impact Classification Factors
1. Global Warming Potential (GWP)
2. Human Toxicity Potential (HTP)
3. Acidification Potential (AP)
4. Eutrophication Potential (EP)
5. Aquatic Toxicity Potential (ATP)
6. Non-Renewable/Abiotic Resource Depletion Potential (NRADP)
7. Ozone Depletion Potential (ODP)
8. Photochemical Oxidants Creation Potential (POCP)
Methodology
In the impact assessment interpretation of the LCI data,
Environmental impact potential,
Where: Bjx = burden (release of emission j
or consumption of resource j per functional unit)
ec1 = characterisation factor for emission j
continues …
Non-renewable/abiotic resource depletion potential
is calculated using :
Where: Bj = burden
(consumption of resource j per functional unit)
ec1 = estimated total world reserves of resource j.
As defined by Adisa Azapagic et al (2003, 2004) in Polymers, the Environment
and Sustainable Development and Sustainable Development in practice –
case studies for engineers and scientists
Life Cycle Impact Assessment (LCIA)
- initial results
GWP
(kg)
HTP
(kg)
AP
(kg)
EP
(kg)
ATP
(m3)
Crop Production
3396
8.11
6.21
1.16
1.1×1016
Water Retting
232
0.61
0.42
0.08
Scutching
1317
Hackling
313
Wet Spinning
3353
Sliver
(pre spinning)
5192
4.88
6.51
1.22
1.09×1016
Yarn
(post spinning)
8612
8.72
6.63
1.23
1.11×1016
continues …
NRADP results..
Crop
Water
production Retting
Diesel :
Oil (kg)
Electricity:
Coal (kg)
Gas (m3)
Oil (kg)
1.75×10-12
Scutching
Hackling
Spinning
1.67×10-15
7.17×10-13
3.68×10-14
3.97×10-16 4.26×10-15
1.7×10-13 1.82×10-12
9.02×10-15 9.29×10-14
1.16×10-13
Contribution to GWP
39%
39%
Crop Production
Water Retting
Scutching
Hackling
15%
4%
Wet Spinning
3%
Discussion
 Agricultural activities dominate
all environmental impact categories
39% of GWP
92% of HTP
94% of AP and EP
 Production of agro-chemicals is not included
(but they do have high embodied energy)
No significant contribution identified for
 Ozone Depletion Potential (ODP)
 Photochemical Oxidation Creation Potential (POCP)
from growth and processing of flax fibres
Discussion..
 spinning
uses
39% of total GWP, and
67% of NRADP
 the embodied energies for flax (no-till agriculture):
59 GJ/tonne for sliver (55 GJ/tonne for glass mat)
89 GJ/tonne for yarn (26 GJ/tonne for continuous glass)
 if flax sliver, not yarn, used as reinforcement,
then magnitude of environmental impacts reduced by
40% for GWP
44% for HTP, and
46% for NRADP
Burdens from …
• no till < conservation agriculture
< mouldboard plough
• organic fertiliser < agro-chemicals
• biological control of pests
< pesticides
• water- < dew- < bio-retting
• sliver < spun yarn
Future Work
 improve the LCIA by considering
both direct and indirect energy sources
 carry out an LCIA for glass fibre production
 study the fibre orientation distribution factor
for flax fibre yarn and sliver
 complete the LCA for production of both
flax and glass fibre
Conclusion
 “green” claim for flax fibres
as reinforcement in composites is not justified
when judged against embodied energy of glass fibres
 conservation agriculture and organic fertiliser
will improve environmental credentials of flax
 environmental impacts could be reduced
by eliminating the spinning operation
References
 Environmental Management - Life Cycle Assessment - principles and frameworks,
ISO 14040:2006. 2006.
 Environment Management - Life Cycle Assessment - requirements and
guidelines, ISO 14044:2006. 2006.
 Turner, J.A., Linseed Law: A handbook for growers and advisers. 1987: BASF
(UK) Limited, Hadleigh.
 West, T.O. and A.C. McBride, The contribution of agricultural lime to carbon
dioxide emissions in the United States: dissolution, transport, and net emissions.
Agriculture, Ecosystems & Environment, 2005. 108(2): p. 145-154.
 Dissanayake, N.P.J., Summerscales, J., Grove, S.M., Singh, M.M., Energy use in
production of flax fibre for the reinforcement in composites, in Advanced
Composites Manufacturing Centre, School of Engineering, University of Plymouth.
2009. p. 1-25. (In submission)
 Azapagic, A., Perdan, S., Clift, R., Polymers, the Environment and Sustainable
Development. 2003: John Wiley & Sons.
 Azapagic, A., Perdan, S., Clift, R. , Sustainable Development in Practice - Case
Studies for Engineers and Scientists. 2004: John Wiley & Sons.
 Azapagic, A., Aquatic Toxicity Potential. Private Communication, 25/02/2009.
Acknowledgements
for their respective travel grants
Faculty of Technology for contribution to registration fees
School of Engineering for the balance of conference costs
Thank you for your attention.
Any questions?