[GreenYes] Re: recyclability of plastics beyond #1 and #2?

[Mike <giuranna.mike@no.address>]

Here are a couple responses to this question that I saved from a year
ago.

1. Years ago when I first started learning about plastics recycling,
I  found this article to be extremely helpful.  It's from the Ecology
Center in Berkeley CA http://www.ecologycenter.org/iptf/recycling/recycledcontent.html
Here is an excerpt:
One factor that complicates plastic recycling is that there are
thousands of types of plastic used for consumer packaging today. The
plastic industry devised a numbering system to categorize plastic into
seven general types. (See sidebar.) Each plastic container must be
separated by type before it can be used again to make a new product.
Of the seven types, only two kinds, Polyethylene Theraphalate, known
as #1, and High Density Polyethelyne (HDPE) - or #2, are typically
collected and reprocessed. And of these two plastic types, only narrow-
neck bottles are typically purchased by remanufacturers because
"bottle-grade" plastic is more easily melted and repelletized and has
established uses. Thus, in Berkeley, only #1 and #2 bottles are
collected at the curb. (The majority of plastic bottles are made from
#1 and #2 plastic.) Yet, many types of plastic containers remain
outside of the recycling loop, such as yogurt cups, plastic bags,
styrofoam, and take-out food
containers. Even though some of these are labeled #1 or #2 plastics,
they cannot be recycled with the bottles. Why? Read on as we answer
this and other frequently asked questions.
Why can't my yogurt cup be recycled? It has a #2 on the bottom, just
like the milk jug you accept. What's the difference? That yogurt cup
may have a #2 embossed on the bottom inside the
well-recognized chasing-arrows symbol, but that doesn't necessarily
mean it's recyclable.
The number on the bottom of the container indicates the type of
plastic it's made from. A yogurt cup may be made of High Density
Polyethylene (HDPE - #2), the same material as a milk jug or bleach
bottle. However, it contains different dyes, plasticizers, UV
inhibitors, softeners, and
other chemicals required to shape it into a cup. This mix of additives
changes the properties of the plastic and makes it incompatible with
the plastic used to make bottles. Adding to the confusion, the
plastics industry began using the chasing arrows symbol with their
numbering system. This has misled people into believing that any
container with a chasing arrows symbol on it is "recyclable." The
industry says it never intended the chasing-arrows symbol to indicate
that a container was recyclable or had recycled content; they just
thought it was a catchy graphic to highlight the identifying number.
Even though the symbol is misleading, the industry has resisted
efforts to modify it.
For more info, try the website for the International Plastics Task
Force http://www.ecologycenter.org/iptf/recycling/index.html
http://www.ecologycenter.org/ptf/misconceptions.html

2. The reason for the distinction is that some are blow molded
(bottles) and some are injection molded (jars) and the processes
require different viscosities, and hence different softening and
melting temperatures. The recycling process requires heating the
material, and the material with the lower melting temperature will
"burn" at the temperatures required to soften the higher melting
temperature plastic.
This is not a hard and fast rule -- different recyclers can handle
different mixtures -- but that's the basic reason. John



On Jan 10, 12:13 pm, Alan Muller <amul...@no.address> wrote:
> Recently the following appeared in the Wilmington (Delaware) News Journal
>
> http://www.delawareonline.com/apps/pbcs.dll/article?AID=2008801090338
>
> My old enemy Pat Canzano, CEO of the Delaware Solid Waste Authority
> (I write about it as the Garbage Empire) is quoted as saying:
>
> "The main impediment to greater recycling of other types of plastic
> is that no one wants to buy them, said DSWA Executive Director
> Pasquale S. Canzano."
>
> "The market drives the process," Canzano said. "It doesn't make any
> sense to collect anything you can't market. Right now the people who
> are taking even single-stream [mixed] recyclables do not want
> margarine tubs, yogurt containers, the higher plastics. They see them
> as contaminants rather than recyclables."
>
> "The state authority expects to double its recycling volume next
> year, to as much as 40,000 tons, as curbside pickup programs expand.
> But Canzano said the authority has no immediate plan to expand
> plastics recycling beyond narrow-neck bottles."
>
> "Rigid plastics are banned from those curbside collections because
> they contaminate the recyclable plastics."
>
> Can anyone give me some quick ammunition for responding to
> this?  Prices of the whole range of recovered plastics?
>
> Thanks,
>
> am