Environmental Engineering Reference
In-Depth Information
not on water. Bottled water bottles are excluded in forty-four states. In
2007, Americans drank more than 30 billion single-serving bottles of
water (7 billion gallons), for which they paid no deposit. Most end up
in landfi lls. Less than one-fourth are sent to be recycled.
In October 2009, North Carolina banned all rigid plastic containers
from landfi lls. This includes any bottles with a neck smaller than the
container itself. Such a standard will prohibit not only soda and water
bottles, but ketchup, milk, salad dressing, vinegar, pancake syrup, and
other containers as well.
Most soda and water bottles are made of PET plastic (polyethylene
terephthalate). North Carolina, which is building the nation's largest
facility to recycle these bottles, already has the second largest recycling
facility in the United States for HDPE plastic, the other commonly used
plastic bottle resin, which can be found in detergent bottles and milk
jugs. PET and HDPE form 96 percent of all plastic containers. But com-
panies specialize in recycling either PET or HDPE; only 5 percent of
companies recycle both types of plastic.
After bottles are collected, they are taken to a materials recovery facil-
ity where they are condensed into large bales for shipping. Each bale
weighs from 800 to 1,200 pounds and can contain 6,400 to 9,600 bever-
age, food, or nonfood bottles. The bales are shipped to a plastic reclaimer,
where a machine rips apart the bales, and the pieces are then machine-
shredded into tiny fl akes. The fl akes are washed, dried, and melted, and
the melted plastic is extruded into pellets and sold to be developed into
various plastic products.
In many PET applications the pellets are spun into a very fi ne thread-
like material that can then be used to make carpets, clothing, or fi lling
for jackets and quilts. The thin plastic is also a good insulator. HDPE
pellets are melted and extruded into plastic lumber or pipe and can be
blow-molded into plastic bottles, or injection-molded or thermoformed
into plastic containers, garden products, sheet, and packaging.
Recycling a single plastic bottle conserves enough energy to light a 60
watt light bulb for 6 hours. Recycling 1 ton of plastic bottles saves 200
cubic feet of landfi ll space.
The Biota company in Colorado believed it had a solution to plastic
bottle refuse: a biodegradable bottle. It made water bottles out of bio-
degradable plastic made from cornstarch, and used 20 to 50 percent less
energy to manufacture them than to make petroleum-based bottles.
Approximately 17 million barrels of oil are used to make plastic water
bottles, enough to fuel about 100,000 cars. The company said that while
