Resource Recovery

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Resource recovery

Resource recovery is the process of recovering materials or energy from solid waste for reuse . The aim is to make the best use of the economic, environmental, and social costs of these materials before they are permanently laid to rest in a landfill . The Environmental Protection Agency (EPA) and environmentalists have set up a hierarchy for resource recovery: reduce first, then reuse, recycle, incinerate with energy recovery , and landfill last. Following the hierarchy will cut solid waste and reduce resources consumed in production. Solid waste managers have turned to resource recovery in an effort to cut disposal costs, and the hierarchy has become not only an important guideline but a major inspiration for local recycling programs.

After the industrial revolution made a consumer society possible, garbage was considered a resource for a class of people who made their living sorting through open dumps, scavenging for usable items and recovering valuable scrap metals. Once public health concerns forced cities to institute garbage collection and dump owners began to worry about liability for injuries, city dumps were for the most part closed to the public. Materials recovery continued in the commercial sector, however, with an entire industry growing up around the capturing of old refrigerators, junk cars, discarded clothing, and anything else that could be broken down into its raw materials and made into something else. That industry is still strong; it is represented by powerful trade associations, and accounts for three-quarters of all ocean-borne bulk cargo that leaves the Port of New York and New Jersey for foreign markets.

The Arab oil embargo of the 1970s focused attention on the fact that natural resources are limited and can be made unavailable, and environmentalists took up the cause of recycling. But only after a barge loaded with New York City garbage spent months stopping in port after port on the eastern seaboard because it was unable to find a landfill was the real problem recognized. There were too few places to put it. The places that did take garbage often leaked a toxic brew of leachate and were seldom subject to environmental requirements.

Environmental restrictions on waste disposal, however, began to change. The EPA required that landfills be lined with expensive materials; states began mandating complicated leachate collection systems to protect groundwater . Amendments to the Clean Air Act of 1990 changed the regulations for garbage incinerators and waste-to-energy plants, which capture the energy created from burning trash to run turbines or to heat and cool buildings. These facilities were now required to install scrubbers or other devices for cleaning emissions and to dispose of the ash in safe landfills. The result of all these changes was a dramatic increase in the cost of dumping; as the price shot up, municipal leaders took notice. Economics joined environmentalism to support recycling, and those charged with managing solid wastes began to look for ways to get the most out of their trash or avoid creating it altogether.

Reduction—cutting waste by using less material to begin with—is at the top of the resource recovery hierarchy because it eliminates entirely the need for disposal, while avoiding the environmental costs of using raw materials to make replacement goods. Waste reduction ,or source reduction, requires a change in behavior that many say is unrealistic when both the culture and the economy in the United States are based on consumption. However, manufacturers have responded to consumer demands that products last longer and use fewer resources. The durability of the average passenger tire, for example, nearly doubled during the 1970s and 1980s. Makers of disposable diapers advertise the fact that they have reduced diaper size so that they take up less space in landfills.

Reuse also cuts the need for raw materials. Perhaps the best example is the reusable beverage bottles that were widely used until the second half of this century. Studies have shown that reusing a glass bottle takes less energy than making a new one or melting it down to make a new one.

Recycling has become a popular way to make new use of the resources in old products. In its purist and most efficient form, recycling means turning an old object into the same kind of new object—an old newspaper into a new one, an old plastic detergent jug into a new one. But new uses for certain materials are limited, and some laws prevent recycled plastic from coming into contact with food; in such cases old items can only be made into lesser products. Recycled plastic soda bottles, for example, can be used in carpeting, television sets, and plastic lumber. The act of recycling itself also uses energy and causes pollution . Materials must be shipped from drop-off site to the remanufacturer and then to producer before they can be returned to the retailer. Grinding plastic into pellets takes energy, and cleaning old newsprint produces by-products that can pollute water. Another drawback to recycling is the unstable price of materials, which has caused some solid waste managers to reevaluate local programs.

After composting , the resource recovery hierarchy lists incineration with energy recovery. As the last option before landfilling, incinerators or waste-to-energy plants only burn what cannot be recycled, and they can recover one-quarter to one-third of their operating costs by selling the energy, usually in the form of electricity or steam. But incineration also produces waste ash, which can contain toxic materials such as lead or mercury . Incinerator ash often meets EPA standards for hazardous wastes, but because it mainly comes from household garbage, it is considered nonhazardous no matter what is detected, although this may change in the future. Other hazardous materials escape out the stacks of incinerators in the form of air pollution , despite high-tech scrubbers and other pollution controls. Environmentalists also maintain that the resources used in making materials that are incinerated are lost, despite the energy that is produced when they burn. They claim that waste-to-energy proponents have adopted the term resource recovery for the process in an effort to mask its problems and put an updated face on an industry that once was unscientific and uncontrolled.

Last on the list is landfilling. Although the United States has potential landfill space to last centuries, much of it is socially or environmentally unsound. Even with extensive liner systems, landfills are expected to leak chemicals into groundwater. Most communities, moreover, are unwilling to have new landfills as neighbors, and citizens groups throughout the country have demonstrated an increasing ability to keep them out through sophisticated protests. Finding space for new landfills has become a nightmare for elected officials and public works managers.

Despite their need for solutions, the resource recovery hierarchy does not always prove practical for local officials who are usually faced with tight budgets and the restrictions of democratic politics. Many of the advantages of the methods at the top of the hierarchy, such as waste reduction or recycling, are distant in either time or geography for many municipalities. A city might be hundreds of miles from the nearest plant that recycles paper and from the forests that might benefit from an overall decrease in demand for trees, for instance. In such a case, recycling paper makes little sense on a small scale. Environmentalists believe that the solution is for manufacturers and solid waste managers to make decisions together. Finding the most efficient use of resources derived from both virgin materials and recovered from wastes may have to be considered regionally or nationally to be fully realized.

[L. Carol Richie ]