Recycling

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Recycling

Recycling is a method of reusing materials that would otherwise be disposed in a landfill or incinerator. Discarded materials that contain glass , aluminum , paper , or plastic can be recycled by collecting and processing them into raw materials that are then used to manufacture new products. Recycling has many benefits: it saves money in production and energy costs, helps to conserve stocks of virgin resources, and decreases the amount of solid waste that must be disposed in landfills or incinerators.

The concept of recycling is not a new one. At the turn of the twentieth century, about 70% of the cities in the United States had programs to recycle certain useful materials. During World War II, 25% of the waste stream was recycled and reused. In 1960, however, only 7% of the waste stream was recycled, but since the early 1970s this has risen along with environmental consciousness, and the recycling rate was about 17% in 1990.

Process

Recycling is a four-step process. The first step is collection and separation from other trash. The second is reprocessing into a raw material, and the third is manufacturing into new products. The final step is the purchase and use of recycled products by consumers, including individuals, businesses, and government institutions.

Although this is a simple formula, recycling faces much controversy and is governed by complicated legislation. Key issues in the debate are how to make recycling more practical, and how to create favorable economics by developing markets for recycled goods. Many states are trying to encourage recycling by passing laws to favor recycling activities, such as tax credits, disposal bans, or regulations governing the recycled content of certain materials (such as newspaper). Although there is disagreement about how some of these laws and regulations should be designed and implemented, there are two issues that are more-or-less agreed upon. One is that fees for the disposal of garbage need to reflect the full costs of that service, and the other is that consumers should be charged for the amount and types of material that they discard.

The biggest problems that recycling faces are poor markets for many recyclables, and poor technology to accomplish effective recycling. There must, of course, be sufficient industrial demand for recycled materials, and also a healthy demand from consumers for products manufactured from those materials. For example, in the northwestern states, it is relatively easy to recycle newspaper, because there are paper mills in the region able to perform this function. In other areas, however, there is more difficulty in recycling newspaper because there are no local mills. These may areas suffer significant fluctuations in the price paid for used newspaper, leading to financial instability in their recycling programs.

Legislation

Legislation has a powerful role to play in encouraging or creating both a supply of recyclables and a market for recycled goods. For example, places with legislation mandating a deposit-refund system for containers (such as soda bottles) have acted to increase the supply of recyclable material. This sort of legislation requires that consumers pay a deposit for each container of soda, beer, or other beverage that they buy from retailers, and later obtain a refund of their deposit when they return the container for reuse or recycling.

Bans on the disposal of certain materials are another useful method for diverting waste from landfills and incinerators, and thereby increasing the availability of recyclable materials. Bans are a controversial approach, but they can be successful in prompting consumers to participate in recycling programs. Items that are commonly banned from disposal sites include lead-acid automobile batteries, tires, yard trimmings, and used motor oil.

Other kinds of laws can also help increase the demand for products manufactured from recycled materials. Some states require that more than a certain percentage of product be comprised of recycled material. This mandate has helped to save newspaper recycling programs, which were collapsing in the 1980s. A number of states (including Arizona, California, Connecticut, Illinois, Maryland, Missouri, North Carolina, Oregon, Rhode Island, Texas, and Wisconsin) and the District of Columbia require a minimum content of recycled fiber in newspapers printed within their jurisdiction.

Some government agencies require that labels list the environmental benefits of certain kinds of products, including their content of recycled materials. This gives consumers an opportunity to use information about environmental issues before making an informed decision to purchase particular goods.

Policies

Utilization rates and procurement polices are other methods used to promote the use of recycled material by industry. Utilization rates allow greater flexibility than minimum-content rules. The manufacturer is still required to use set amounts of recovered material in their manufacturing process, but they have more latitude in selecting how the material is used. For example, a manufacturer might use the material for its own products, or arrange to have the recovered material used elsewhere.

Procurement policies are mandates that require large government agencies, which have enormous purchasing power, to set aside some portion of their budget for the purchasing of recycled products. This helps to create more favorable economics for recycling. For example, the Environmental Protection Agency (EPA) requires that a certain proportion of its purchases, and also that of other federal agencies, involves such products as recycled paper, re-refined motor oil, and other items made from recycled materials. A disadvantage of affirmative procurement policies is that prices may be higher for recycled products, and there may be problems with the availability and quality of some goods.

Recycling collection programs

There are four commonly used methods for collecting recyclable materials: curbside collection, drop-off centers, buy-back centers, and deposit/refund programs. The fastest growing method is curbside collection. There are three major ways in which recyclable materials are collected through curbside programs: mixed wastes, mixed (or commingled) recyclables, and source-separated recyclables.

Mixed-wastes collection is essentially a modification of the conventional municipal waste-collection process. It involves the sorting of recyclables at a central facility, using a combination of automated methods (such as magnets to sort iron-containing material) and hand-sorting. An advantage of this method is that it does not disrupt the regular schedule of trash pick-up in the community.

Mixed recyclables are separated from other trash by householders and businesses, so that two streams of material are picked up at curbside: trash and recyclables. This method has a lower contamination level of the recyclable stream than the mixed-wastes collection system. Public education is necessary if this program is to work well, so that people know what is recyclable and what is not.

Source separation involves householders and businesses performing a higher level of sorting before pickup. The advantage of this method is that the recyclable materials are well-sorted and can be sold at a higher price. The disadvantages are that source separation requires a high participation rate, as well as more or more-complex collection vehicles.

Drop-off centers are central places where householders or businesses can take their accumulated recyclables, rather than having them picked up at-site. This method requires public education and a high participation rate if it is to be effective. Like other collection systems, it works best if there are positive incentives to encourage participation (such as monetary redemptions), or negative ones to not participating (such as landfills refusing to accept recyclable materials, or charging a significant fee to take them).

Redemption or buy-back centers are similar to drop-off centers, except they purchase recyclable materials. Buy-back centers pay a unit-fee for such recyclable materials as newspapers, soda cans, glass, and plastic bottles. This system is also effective for the collection of metals, such as aluminum, lead , and copper .

After recyclables are collected and sorted by any of these methods, they are sent to a materials recovery facility (MRF), where they are prepared for re-manufacturing. A MRF can typically process 25-400 tons of material per day. Sorting is done both manually and mechanically. Newspapers are usually the major paper item, but MRFs also sort corrugated boxes, telephone books, magazines, and mixed-paper materials. MRFs also process aluminum, glass containers, plastic bottles containing polyethylene terphthalate (PET), and milk and detergent bottles containing high-density polyethylene (HDPE).

Recyclable materials

Numerous materials can be recycled or reused from the waste stream, including: aluminium cans and other materials, automobiles and steel appliances, clothing, construction waste, copper piping, furnishings, glass, lead-acid batteries, used motor oil, paper (cardboard, high-grade paper, newspaper, mixed paper), plastic bottles, tires, wood waste, and yard trimmings and other organic materials (which can be composted).

All of the above items can be reprocessed into new products. Recycled paper, for example, can reprocessed into newsprint, writing paper, tissue , packaging, paperboard, and cellulose insulation. Plastic bottles can be reprocessed into auto parts, fiberfill, strapping, new bottles, carpet, plastic wood, and plastic bags. Some other materials can be reused directly with little or no processing, including used clothing, furniture, and lumber.

Composting

Composting is an increasingly popular method of recycling organic materials. It is an ancient practice; and low-technology farmers around the world have always composted manure and other organic materials for application to their crops . In fact, composting is one of the central activities in all methods of organic agriculture.

Any raw, organic materials containing vegetable or animal matter can be successfully composted. The composting reactions are mostly carried out by bacteria and fungi , along with other microorganisms and invertebrates of many kinds (earthworms can be highly effective in this regard). Composting proceeds best if the material is kept warm and is occasionally turned to increase the availability of oxygen . Composting can be done by individual householders, or in large, centralized, municipal facilities. The end-product is an amorphous, organic-rich material (or compost), which is extremely useful as an amendment to increase the organic-matter concentration of soil and enhance its tilth. Compost is also useful as an organic fertilizer. The compost can be given or sold to local horticulturists, or to farmers.

Household materials that can be readily composted include: tree leaves, lawn clippings, vegetable and fruit peelings and other food left-overs, seaweed, shredded cardboard, newspapers, other kinds of paper, dryer lint (if derived from cotton and other natural fabrics), livestock manure, hair, feathers, and meat. Egg-shells and wood ash can also be added to increase the nutrient content and neutralize acidity. Materials that should not be added to composters include: seed-bearing weed residues, walnut or eucalyptus leaves (these contain natural chemicals that can be toxic to cultivated plants), or dog and cat dung.

Preparing the compost

Excellent compost bins can be purchased, or they can be easily built using chicken wire and a wooden frame. The bottom of the bin should be lined with dried grass, leaves, or shredded paper. As additional organic matter is added to the pile, it can be watered if necessary and mixed to increase oxygenation. An efficient temperature for composting is about 130-140°F (54-60°C). Depending on the organic mix and time of year, a well-humified compost will develop within two to six months. Many gardeners have been composting their organic matter for years. It has only been in the past decade or so that the broader public has been encouraged to compost on a larger scale.

The "compost man"

Clark Gregory is a soil scientist who has been a driving force in the growing popularity of composting. When he was the composting supervisor for Fulton County, Georgia, Gregory became known as the "compost man." He claims that up to three-quarters of the material that is typically discarded in landfills is potentially biodegradable through composting. Gregory advocates the use of large-scale, comprehensive composting programs in all local communities, as a way or drastically reducing the amounts of solid waste that have to be landfilled. In many municipalities, just the composting of soiled paper, yard clippings, and food scraps would reduce the solid waste stream by 40%, while also helping to reduce the cost of garbage collection and disposal.

Economic benefits

Composting programs have highly favorable economics, compared with the land-filling of organic waste. For example, a composting program in Seattle is saving taxpayers about $18 per ton of organic waste, and is diverting about 554 lb (252 kg) of garbage per household out of landfills each year. Similarly, the town of Oyster Bay, Long Island, instituted a leaf-composting program that generated 11,000 tons of compost for use by local gardeners, while saving $138 per ton previous spent to truck the leaves out of state for land-filling. The town of Bowling Green, Kentucky, composts more than 0.5 million cubic feet of leaves each year, producing humus that is sold for $5 per cubic yard, while saving $200,000 annually in disposal costs. Islip, New York, saves $5 million each year by composting grass clippings, which were once exported along with other garbage by barge to the Caribbean. If every county in the United States instituted composting programs of these kinds, the overall net savings could be $1.6 billion per year.

Zoo-Doo

Some zoos have become creative in composting and marketing the manure of their exotic animals. The Zoo-Doo Compost Company sells composted animal manure to novelty buyers and to organic gardeners. More than 160 zoo stores and 700 other retail outlets carry Zoo-Doo for sale to gag-gift buyers. In addition, gardeners buy larger quantities of the Zoo-Doo, which has a favorable nutrient ratio of 2-2-2 (2% each of nitrogen , phosphorus , and potassium), and is an excellent soil amendment as well as an organic fertilizer.

Researchers, environmentalists, and program administrators all agree that creativity will be one of the keys to solving many waste problems. Many landfills are nearing their carrying capacity , and most of the older ones will be closed by the year 2005. Recycling, composting, and reusing are all environmentally and economically beneficial ways of greatly reducing the volume of the solid waste stream.

Resources

books

Beatley, Thomas. Green Urbanism. Washington DC: Island Press, 2000.

Braungart, Michael, and William McDonough. Cradle to Cradle: Remaking the Way We Make Things. New York: North Point Press, 2002.

Christopher, Tom, and Marty Asher. Compost This Book! San Francisco: Sierra Club Books, 1994.

Earth Works Group. 50 Simple Things You Can Do to Save theEarth. 3rd ed. Berkeley: Earthworks Press, 1998.

Matthews, John A., E. M. Bridges, and Christopher J. Caseldine The Encyclopaedic Dictionary of Environmental Change. New York: Edward Arnold, 2001.

McConnell, Robert, and Daniel Abel. Environmental Issues:Measuring, Analyzing, Evaluating. 2nd ed. Englewood Cliffs, NJ: Prentice Hall, 2002.

Powelson, D.R., and M.A. Powelson. The Recycler's Manual for Business, Government, and the Environmental Community. New York: John Wiley and Sons, 1997.

Strong, D.L., and D. Kimball. Recycling in America: A Reference Handbook. 2nd ed. Contemporary World Issues Series. Santa Barbara: ABC-CLIO, Inc., 1997.

other

Recycling Resource [cited March 2003]. <http://www.resourcerecycling.com/indices.html>.

"World's Shortest Comprehensive Recycling Guide." InternetConsumer Recycling Guide [cited March 2003]. <http://www.obviously.com/recycle/>.

Kitty Richman

KEY TERMS

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Composting: —The process by which organic waste, such as yard waste, food waste, and paper, is broken down by microorganisms and turned into a useful product for improving soil.
Decomposers: —Bacteria, fungi, and other microorganisms that break down organic material.
Humus: —Organic material made up of well-decomposed, high molecular-weight compounds. Humus contributes to soil tilth, and is a kind of organic fertilizer.
Incinerator: —An industrial facility used for the controlled burning of waste materials.
Landfill: —An area of land that is used to dispose of solid waste and garbage.
Manure: —Animal dung.
Microorganism: —Bacteria, fungi, and other microscopic organisms.
Organic material: —Vegetable and animal biomass.
Prefabricated: —Manufactured off-site, usually referring to a construction process that eliminates or reduces assembling.
Virgin material: —Material resources that have not previously been used for manufacturing or some other purpose.