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Recycling Plastics

04/04/2010 11:01 AM

I'm curious (and a little surprised) at the various types/grades of plastic and ability to recycle them. My trash service gives me an extra can for recycled materials. For plastic they say they accept 1, 2, 3, & 5. I'm wondering what is 4, and we just found a 6, are there others? If I have a plastic soda bottle, I can't keep the cap on it. The cap must go in the regular trash.

What do the numbers represent - purity? hardness? what else? Is each number melted/processed separately? And what would happen to the recycled product if there was 4 & 6 in the whole melted mixture?

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#1

Re: Recycling Plastics......

04/04/2010 11:11 AM

Each number represents a different type of thermoplastic. The different types are generally not "mixable" as their physical properties are not the same and they would not mix properly. It's really more complicated than that, but it's close enough for starters.

DECIPHERING THE NUMBERS ON PLASTIC BOTTLES
by JANE BOGNER
SUNDAY, August 4, 2002

Everywhere I go, even at my Pacific Crest Trail base-camp at 10,000 feet in the Sierra, I am asked about recycling plastics. This packaging material is highly used but so poorly regulated that very few consumers understand what can be recycled.

Several weeks ago, I read the" You Can" strip on the Contra Costa Times comic pages. Jax Place answered a question about what can be recycled into new things. He concentrated on plastic packaging confirming what I have said for the past ten years in this column.

There are hundreds of modern plastics with only seven routinely labeled. The plastic industry cleverly put these plastic numbers inside a recycling triangle to make the public think that there is a market for recycling their containers.

Plastics are long molecules made by chemists. Each plastic has a different molecule or set of molecules. Different molecules do not mix with others when plastics are recycled, just as aluminum cannot be combined with glass to be recycled into a new product.

Let's start with #1 PET which stands for Polyethylene terephthalate. Soda bottles as well as some beer and liquor bottles are made from PET along with a variety of other food bottles and trays. PET can be melted and drawn out into long fibers and recycled into carpets, fiberfill for jackets, and fabric for T-shirts and shopping bags which unfortunately cannot be recycled. Manufacturers want recycled PET and buy it. Coca Cola has finally started using a measly 3 percent recycled PET in their bottles. Be aware that local recyclers only accept narrow-neck PET bottles. I have surmised over the years that used PET food containers with sticky food scraps contaminate the recycling machines.

Milk and water jugs are made from number #2 HDPE or high-density polyethylene. Clear HDPE could easily be made into new containers. The colored HDPE (liquid detergent, and shampoo bottles) is generally recycled in plastic lumber. Those tough Tyvek mailing envelopes and white contamination suits are also a form of HDPE and are impossible to recycle.

Vinyl or polyvinyl chloride (# 3 V) could be recycled. It is used for clear food packaging and plumbing pipe. However, collecting it for recycling is cost-prohibitive because there are not enough items made from the material to warrant local factories to recycle it into new products. They are generally used once and tossed.

Low-density polyethylene (# 4 LDPE) is very flexible and made into bags for bread, frozen food, and grocery. Some of these bags are recycled into new bags or plastic lumber such as Trex. This plastic is lightweight and trucking it back for recycling uses more energy than producing a virgin product. Unless there is a recycling factory close by, most LDPE ends up in the landfill. Consider using cloth shopping bags. My husband and I have used the same bags for over eleven years.

Polypropylene (# 5 PP) is made into yogurt, margarine, and other food containers. Like number 3 V, there are not enough containers made from PP to justify collecting it and shipping it to a recycling factory. In places where big industries use PP, there is enough volume for it to be sold for recycling.

Then there's #6 PS - Polystyrene, the plastic that I would ban from the face of the earth. Solid PS is made into compact disc jackets, eating utensils, and take-out food containers. The expanded PS know as Styrofoam is used for packing materials, coffee cups, meat trays, and egg cartons. The cost of moving used Styrofoam is higher than making it from virgin oil. Jax Place reported, "Foam recycling is a scam to make you feel OK about buying it. Don't buy it; PS is buried in landfills." Styrofoam is always found in our local creeks and rivers where birds and fish think it is food clogging up their digestive tracks thus ending their lives.

The last of the labeled plastics is #7 OTHER. I echo Mr. Place's voice, "Don't buy this stuff unless you want to keep it. It can't be sold or recycled." Catsup bottles have wavered between PET and OTHER over the last few years. Lids and imported containers are likely to be made from mixed resins known as OTHER.

Jax Place ends his strip with a P.S.: "Companies that use plastics that aren't really recycled sometimes collect these plastics to make us feel good. It's more about marketing than taking care of the planet."

If you like a product but not the packaging, contact the manufacturer and complain. Web sites and 800 numbers are listed on the package. If they don't take the hint, the government should step in and set recyclable packaging standards.

VALCORE Recycling Vice President Jane Bogner's "A Sorted Affair" is published every other week in the Times-Herald, Community Outlook Section. For recycling information call Genie Kaggerud, VALCORE Recycling Manager at 645-8258 or visit www.VALCORErecycling.org.

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#2

Re: Recycling Plastics

04/05/2010 9:51 AM

If I were you, I'd take any plastic bottle that contained a beverage to a recycling center, where you take your aluminum cans and glass bottles myself and collect money for the pound for it.

All other plastic I'd put into the recycling can your sanitation company provided for you.

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#3

Re: Recycling Plastics

04/05/2010 12:29 PM

Check "Resin Identification Code" on Wikipedia.

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#4
In reply to #3

Re: Recycling Plastics

04/05/2010 3:43 PM

Thanks greatly! In that Wiki entry I found this link to a nice chart - http://www.americanchemistry.com/s_plastics/bin.asp?CID=1102&DID=4645&DOC=FILE.PDF

Still wondering what would happen if all numbers were put in a pot and melted. Would this be a Frankenstein plastic that would never just mix or mold? Maybe just look like a lumpy mess (as when I try to make gravy?)

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#5

Re: Recycling Plastics

04/05/2010 5:02 PM

There are so many blends and variations that putting them in a big pot makes about as much sense as the current system. Expecting the consumer to know that white beaded EPS/PE polymer is not the same as beaded EPS, even though they both have the chasing arrows 6, is pure folly. Trying to separate these after collection is another headache.

There needs to be a mass utilization method that can take all blends and convert to fuel or kitty litter or whatever. Plastics are here to stay and more power to them, but the industry needs to resolve this issue before the Enviros solve it for us.

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#6

Re: Recycling Plastics

04/10/2010 1:00 PM

You can convert all types of plastics in to fuel.

STEPS mumbai and Aalka Zadgaonkar at Nagpur in India have developed the process.

Google search for plastic to petrol can give you information.

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