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[GreenYes] Small Volume Plastics
    In the past week there has been a good deal of email traffic about what
to do with regard to small volume plastic containers (i.e. those with SPI
code nos. 3-7).

    Here is the breakdown of the proportion of each resin used in packaging
in the U.S. in 1998 from Modern Plastics magazine (with apologies for the
loss of columns in plain text).

Proportion of Resin in Bottles

Millions of Pounds in 1998 Produced in U.S.

PET Soft Drink1,975 31.3%
PET Custom1,570 24.9%
HDPE Food1,334 21.1%
HDPE HIC+Oil1,224 19.4%
PVC145 2.3%
LDPE62 1.0%
PP190 3.0%
Total6,311 100.0%

    The small volume resins, then, are only 6.3% of the packaging stream.
With all plastic containers comprising only 4.9% of generated waste,
according to
Franklin, that means the small volume resins are only 0.3% of MSW.

    One can look at the issue of these small volume resins two ways. One way
is to ask whether product should be packaged in those resins at all.  The
other way is to devote the resources that would be necessary to recycle an
extremely small volume material (remembering that, as a general rule, it is
ruinously expensive to set up an infrastructure to handle small volume


    As to the first, the answer depends upon the resin.  Polypropylene (PP),
or no. 5, is a polyolefin that is in the same resin family as high density
polyethylene (HDPE), and the two are highly compatible. Indeed, a little
known fact is that many molders of copolymer (i.e. pigmented) HDPE bottles
deliberately add a little bit of PP, along with other additives, to improve
performance. It would be good if there were tests run to determine the
threshold of concern for PP levels in copolymer HDPE, but, intuitively, I
find it hard to imagine the relative proportion of PP bottles turning up in
a recycling program being of any concern, even for bottle-to-bottle
recycling, if it is just thrown in with the colored HDPE, which is what is
almost certainly what is currently happening since it visually looks so
similar.  If anyone has any data to suggest otherwise, however, please share

    As to polystyrene (PS), or no. 6, these will be found in the container
category primarily in yogurt cups.  For those programs taking injection
grade HPDE (yogurt cups and ice cream containers), the PS would probably be
a matter of concern, unless the end product were extremely low end
applications.  This, then, could be of concern to some localized programs,
though not to most.

    As to polyvinyl chloride, however, the answer is quite the opposite.
Without consuming too much of your time, the bottom line is that this single
resin, occupying only 2% of the plastic bottle stream, and accounting for
only about 1% of PVC sales (most of which is in construction), is the single
greatest factor keeping PET recycling underwater for most of its commodity
cycle.  Because the two resins, which are completely incompatible down to 20
ppm, are visually indistinguishable on the sorting line, expensive, and
imperfect, optical sortation equipment and advanced techniques must be

    On a raw basis, the capital and operating costs of that optical
equipment, in the average case, are about 1.4 cents/lb.  However, this
doesn't account for the fact that, just to produce the purity required by
fiber markets results in false positives that incorrectly kicks out PET
along with the PVC, nor for the yield loss.  Factoring in for these
increases that raw cost to 2.6 cents/lb.  But, that, in turn, doesn't
account for the fact that even using these optical scanners cannot produce
the higher purity levels required for the bottle end markets.

    This is of major concern because bottle markets in general pay net 6-7
cents more per pound, and Coke's commendable commitment to use 10% recycled
content in their bottles opens up a new world when the higher paying bottle
markets loom as a brass ring for recyclers to grab in appropriate cases that
can significantly ratchet up their revenues.

    That is to say, local recyclers are losing about 9 cents per pound
because of the teeny residual presence of PVC -- which provides no
performance or cost advantage over PET!  This is more than the trended 8
cents per pound that we're getting FOB for our clear/green PET bales!!!!!!!!

    If there is nothing that any of us do before we die, there would be no
greater legacy to leave to our recycling descendants than to undertake the
necessary effort to convince packagers to stop using this resin.


    On the other hand, there is the alternative view that we ought to devote
whatever energies are necessary to recycle that 0.3% of MSW which consists
of these small volume resins, even though it is economically impossible to
recycle anything in such small volume because the handling systems, which
are expensive, can only be spread over such small volumes, raising unit
costs to astronomical and near-insane levels.

    It is for that reason that those who follow this thread wind up either
shipping mixed bales to China or some extremely low end application that
claim that they can blend all resins without the need for sorting.  China is
not an answer for even the West Coast, because, beyond the fact that no one
knows precisely what is done with it over there, that market has, can, and
will intermittently dry up over night and then where are you. A recycling
manager can't tell his residents to sort only 1&2's this month and all
plastics next month.

    Nor are the black box salesman worth our time because, beyond the fact
that they go out of business all the time, they are a no-pay market. Do we
want to lose what ought to be 12-16 cents per pound for 94% of our bottles
in order to claim bragging rights that, even though we've lost all that
revenue, we got the last 6%.  Wouldn't it make a lot more sense pursuing the
frontiers where the real gains can be made such as residential mixed paper,
expanded organics recovery or C&D recycling where we're talking about
increasing recycling from 10 to 40 percentage points!

    Then there is the American Plastic Council's all bottles program. That's
a whole other multi-page discussion, but, for the moment, suffice it to say
that what it really accomplishes is creating the false impression that PVC
is recyclable -- when it is not -- which is diametrically the opposite of
what we desperately need to if we are going to be able to convince the
consumer and packager to remove PVC from the shelves. The research that APC
has offered up in support of their claim that all-bottles increases nos. 1&
2 recovery in fact, shows a mixed bag with many examples of reduced 1&2
recovery, but in any case all of it mired in improper testing procedures.
The increased recovery which is shown is all explainable by the fact that
the introduction of all-bottles is accompanied by increased general
education advertising efforts that increases recovery regardless of the


    Bottom line, don't worry about the small volume resins, except for PVC,
and that is where our efforts desperately need to be directed to make it
possible for PET recycling to thrive, which it can and will, if we only come
together and act in our own economic interests.


Peter Anderson
4513 Vernon Blvd. Suite 15
Madison, WI 53705
(608) 231-1100
Fax (608) 233-0011

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