The Recycling Market
Today's recycling market is as sophisticated as any other business, with stocks traded and futures projected. Processes continue to evolve to provide better quality and more consistent sources of recycled materials, and manufacturing changes allow the use of recycled materials. As these trends continue, recycled products will become a viable and vital component of manufacturing. It's likely that with improved recycling processes and a consistent demand, recycled materials will become more economical. The three main recycled materials are plastics, metals, and paper, and each has its own markets and uses.
Plastics
Plastic bottles are everywhere from the refrigerator to the laundry room, each with an arrowed triangle and number stamped on the bottom.
The numbers associated with recycled plastic can be confusing, so here's the rundown:
No. 1 plastic is polyethylene terephthalate, also known as PETE or PET. It's used for soda bottles and other food containers. PETE can be recycled into fiberfill for pillows and sleeping bags and other food and drink containers.
No. 2 plastic is high-density polyethylene, or HPDE. Milk jugs are made from nonpigmented HPDE; laundry detergent bottles are manufactured using pigmented, or colored, HDPE. If separated well, these plastics can be recycled into the same color bottles and jugs.
No. 3 plastic is polyvinyl chloride, or PVC. It's used to make PVC pipe and medical tubing. Orange traffic cones and garden hoses are also usually made out of recycled PVC.
No. 4 plastic is low-density polyethylene, commonly known as LDPE. It's used to make squeeze bottles for condiments like jelly and ketchup. LDPE can be recycled into landscape timber and garbage-can liners.
No. 5 plastic is polypropylene, or PP. It's used for storing food like yogurt and can be recycled into a variety of items from medicine bottles to battery cables.
No. 6 plastic is polystyrene. It's used to make meat trays used by grocery stores along with plastic cups and plates. When recycled, polystyrene is turned into foam packing and license-plate frames.
No. 7 plastic incorporates all other plastics not included in the first six categories. It's used to make large water bottles and plastic lumber.
Once sorted at the recycling facility, plastics are baled and sent out for processing. There the plastics are cleaned, possibly sorted by color, and converted to flakes and pellets. Then they're sold to manufacturers for use as feedstock.
Metals
Everything from aluminum soda cans to used engines can be recycled; it's just a matter of getting them sorted and to the right place. Currently, whole engines can be sent overseas to countries such as India and China where labor rates are low and it pays to break down engines manually into separate components like copper wiring and steel casing for recycling. The same shipping companies that bring merchandise from China and India to the United States take back our recyclables. It's a cycle.
Aluminum cans are one of the easiest items to recycle. From the time a can is turned in for recycling, it will take about sixty days for it to be sorted, cleaned, processed, filled, and back on a store shelf.
Aluminum is sorted by composition because it contains alloys such as iron, silicon, and zinc. It's then sent to a processor where it's melted and either cast, rolled, or extruded. A variety of aluminum products can be recycled including pots, pans, and even baseball bats. Once recycled, aluminum sheets and forged aluminum can be used to make drink cans, car parts, and construction materials. Aluminum can also be made into a powder and used for a variety of products like explosives and decorating materials.
Paper
Like other materials, paper is sorted and baled in the recycling facility. Bales of flattened cardboard and bales of mixed paper and newsprint are sold to mills for processing. Processing paper requires a progression of different treatments.
According the Paper Industry Association Council, 86 percent of Americans have access to curbside or drop-off paper-recycling programs. More than 50 percent of the paper used is recycled. That adds up — every ton of paper that is recycled saves 3.3 cubic yards of space in a landfill.
When paper comes to the mill, it is pulped into fine pieces and water is added to make slurry. The slurry is run through a screen so pieces of glue and other contaminants can be removed. From there, the soupy mixture is cleaned by spinning it around in a cone-shaped cylinder that causes heavy objects like staples to fall out. The pulp mixture is then de-inked, or brightened. During this process, sticky inks are removed. The mixture is then bleached to remove any remaining color. The end result is paper pulp that is ready to be used for processing. The bleaching process has many negative environmental impacts since it usually involves chlorine. In the water, chlorine can react with organics such as dead leaves to form trihalomethanes (THMs), which have been found to be carcinogens. New green alternative bleaching processes are being developed to eliminate these concerns.
