Title: : A pragmatic comparison of Sacks to Sustainably manage the Yuck factor Biodegradable Plastics versu
1A pragmatic comparison of Sacks to Sustainably
manage the Yuck factor Biodegradable Plastics
versus Conventionals and other Sacks Jim
Cairns, EPAS/Environmental Plastics Advisory
Servicesor Enthusiastically Promote Allthings
Sustainably
- Coast Waste Management Conference Victoria March
29th 2007 - Freely updated and adapted from EPAS Presentation
at - 31st Annual RCBC Conference
- Harrison Hot Springs
- June 2, 2005
2Disclaimer
- This is not a sales pitch for
- any specific class of plastic
- Or
- Cellulosic
3EPAS Position
- Responsibly managed, plastics are
- more part of the solution than the problem.
- Might adequately exhausted high calorific value
plastics be considered as energy - THEY are after all sourced from Natural Gas ?
- Likewise low calorific value compostables be
converted into quality compost
4Degradability of plastics
- Virtually all plastics degradable
- Rate of degradation may be adjusted
- Cost / performance governs selection
5History of biodegradable plastics
- Not a new class of plastics
- Have been around for about 20 years
- Over a decade ago took a nasty knock
- Starch added to conventional plastic was promoted
as way to go - Proven to be ineffective, tainted plastics image!
6Renewed interest
- Continued growing public awareness
- Potential application to high-volume organic
discard stream - Industry giants enter Dupont, Cargill-Dow, BASF,
Eastman, Proctor Gamble, Novamont,
Polargruppen. Archer Daniel Midlands - Recognize need for performance certification to
avoid repetition of starch disaster
7Two major types
- Biodegradable Plastics (Bios)
- Made from agricultural sources or fossil fuel
sources BASF - One-step bio-degradation
- Oxo-biodegradable Plastics (Oxos)
- Made from conventional fossil fuel sources
- Modified with additives for controlled life
- Two-steps disintegration, then biodegradation
8The Bios overview
- Agricultural sources
- corn -gt starch -gt sugars -gt polyactide polymer
plastic (PLA) or PHAS Metabolix - Petrochemical sources
- Certain monomers will de-polymerize when wet,
becoming acids and alcohols which are composted
by bacterial action - Relative cost, possibly lower physical
performance, than conventional or Oxo plastics
9The Bios agricultural sources
10Agricultural Bios closed-loop
11The Bios certification
- Producers represented by Biodegradable Products
Institute ( BPI) (www.BPIworld.org) - Meet standards established to assure performance,
credibility (ASTM 6400, ASTM 6868, EN 13432) - Completely mineralize to water and carbon dioxide
under controlled conditions - BPI members include industry giants (BASF,
DuPont, etc.) - Dow has withdrawn from Cargill Dow . Eastman
has sold Eastar its co-polyester to Novamont
12The Oxos overview
- Petrochemical based plastics
- Modified by use of proprietary chain breakers
(e.g. TDPATM - Totally Degradable Plastics
Additive) - Designed for a controlled lifetime
- Disintegrate then degrade when in adequate
composting environment - Less extra financial cost than BPI products
-
13The Oxos
- Represented by Oxo-biodegradable Plastics
Institute (OPI) (www.oxobio.org) - Meet safety and performance standard (ASTM
D6954-04) - Disintegrate , may or may not compost, no third
party pass / fail certification - OPI membership small relative to BPI.
14Differentiation of ASTM standards
- ASTM 6400/ 6868 EN 13432 (Bios)
- Pass/fail tests for compostability
- Must achieve 60 biodegradation within 180 days
in specified composting conditions - certified by third party testing
- ASTM 6954 04 (Oxos)
- A standard testing guide
- Recognizes oxo-biodegradability as a two step
process - Disintegration (oxidation) and subsequent
bio-degradation to compost
15Independent Oxos
- Not represented by OPI
- Also offer controlled life plastic products
- May or may not meet ASTM standards
16Biodegradable plastics markets
- Collection bags for Source-Separated Organics
(SSO) - Convenience packaging (paper/plastic, deli,
blister) - Disposable cutlery / dishes
- Six pack retention rings
17Biodegradable plastics Potential Benefits
- SSO collection bags avoid negative cosmetic
impact on composts value - Disposable products/packaging convenience of
composting along with organic food residues
18Factors for ConsiderationBio, Oxo, or
conventional?
- Performance (weight / strength)?
- Relative Cost?
- Environmental impacts of ag-based plastic?
- How effectively will Bios / Oxos compost in
wide variety of composting conditions? - Potential impacts of Bios/ Oxos on mechanical
recycling of conventional plastics? - Potential impacts of Oxo additive residues?
19Environmental Impacts?
- Agricultural expansion (to grow more grain for
human, animal, bio-fuels, MTBE replacement)? - Compost value of bios / oxos versus energy
value of exhausted conventional plastics? - Might Bios / Oxos promote littering?
- The Food Plastic Fuel Tussle
20Conclusions
- Many as yet unknown factors.
- Bios and Oxos will enjoy niche markets.
- They may create as many problems as they resolve.
- They are not a panacea.
21The constructive dialogue continues