Congrès International sur l'Analyse du Cycle de Vie Lille ... - avniR

Congrès International sur l’Analyse du Cycle de Vie Lille, Novembre 2011
De la salle (Claire MICHAUD)
Est-il possible de transformer la fibre textile pour réduire les impacts lors d e la phase d’utilisation ?
Anne PERWUELZ
Cette proposition fait partie des solutions envisagées suite aux premiers ACV. Par exemple, une fibre
polyester diminue les impacts lors de l’utilisation et il existe des traitements qui permettent d’éviter le
repassage. Des simulations tentent de déterminer si un gain est bien obtenu lors de la phase
d’utilisation, car ces traitements nécessitent l’ajout d’un polluant lors de la phase de production.
Etude de cas ACV : fibre de cellulose synthétique et fibre de polyester
recyclée
Li SHEN, Chercheur, Université d’Utrecht
I have carried out two case studies of LCA on fiber products. The first case study involved man -made
cellulose fiber, which has been around for 60-70 years. For this fiber, however, the viscose process is
very polluting and has garnered lots of protests. This thus prompted the industry to work on a cleaner
process.
In our case study, we wanted to understand the fiber’s impact and compare it with commodity fibers
such as cotton, polyester and so on. We looked at post-consumer waste incineration, comparing biowaste
and petrochemicals and studied 5 types of man-made cellulose fiber, grouped into viscose,
modal (modified viscose) and tencel, as well as Polyethylene terephthalate (PET) cotton. Our dat a
was provided by the Austrian textile company, Lenzing.
Using cotton as the baseline for our study, we found that cotton is not an energy-intensive product
while polyester and polypropylene are. Cellulose fiber energy requirements vary and tencel fiber
requires low energy compared to viscose. Looking at other impact categories, we found that cotton’s
eco-toxicity is bad. These LCA results gave us no overall conclusion so we performed an additional
normalization test to the mid-point results and applied waiting factors. This showed cotton had the
highest impact due to the chemical use of cotton production. When performing LCAs, it is important to
make everything transparent.
The second case study involved fiber recycling, for instance PET bottles into stab le fiber or filament.
Four recycling cases, including mechanical recycling, semi-mechanical recycling, back-to-oligomer
recycling and back-to-monomer recycling were analyzed. We proposed three allocation methods were
applied: first, the cut-off approach which looks at first life. It is fed into the fiber production, free of
environmental burden, and is a free resource to use. The second approach was waste valuation. In
this approach, waste carries a burden from its previous life. It has a lower impact than primary
production but the distance is also smaller. The third approach was the system expansion method,
which involves larger distances. Waste valuation could be important if more waste is used as a
resource in the future. System expansion is not very eas y to explain to industries but it takes into
account the entire LCA. Luckily we have data to perform this analysis but in paper recycling, previous -
life data is not as available. The methodology still needs to be carried on in the life -cycle community.
Echanges avec la salle
Frédéric CHOME
We have worked with the paper industry and have had similar problems with recycled paper. There is
indeed value in waste that we can use.
De la salle (Laurent NOCA, Lafuma)
Avez-vous prévu d’analyser d’autres fibres textiles, notamment la fibre PLA ?
Li SHEN