Glass Recycling Market Trends, Contamination Problems Discussed
By Jenny Gitlitz

On June 14th, 30 recycling professionals and several area college students gathered at the headquarters of the Rhode Island Resource Recovery Corporation (RIRRC) in Johnston, R.I. to hear two officials of the Container Recycling Alliance (CRA) discuss the state of glass markets in the Northeast. A division of Waste Management-Recycle America, CRA operates eleven beneficiating plants across the country, processing 700,000 tons of cullet annually, or about 25% of the glass recycled in the United States.

Kerry Martin, Container Recycling Alliance (CRA) Area Manager for the Eastern United States and Frank McAuliffe, Manager of the CRA beneficiating (glass processing) plant in Franklin, Massachusetts, made a comprehensive and interesting presentation about glass recycling. McAuliffe and Martin told the group that market trends in the Northeast and along the East Coast were similar to national trends. Color-separated glass collected through redemption ("bottle bill") operations commands the highest market value. CRA is the only beneficiator in the Northeast that will accept non-bottle bill glass, McAuliffe said, despite stable end markets for amber (brown), flint (clear), and mixed-color glass generated by MRFs that process curbside glass.

Markets for green glass, however, remain glutted. According to Martin, there are almost no markets for green glass on the East Coast. Five bottle manufacturing plants have closed in the last five years in New Jersey, Pennsylvania, New York and New England, significantly reducing the number of market outlets available for green glass in the Northeast. He said that Canadian and European bottlers (notably Labatts, Molson and Heineken) are already using about 30% percent cullet in their bottles, using their own domestically recovered glass; they have little demand for imported American green cullet. Although it is technically feasibly to use as much as 100% cullet in bottle making, manufacturers' stringent demands for cosmetic consistency (final bottle color) have constrained their willingness to use more cullet than they already do. In California, the state has mandated that manufacturers use a minimum of 50% secondary materials as feedstock, and many bottle manufacturers are well on their way to meeting this goal.

Because of these market limitations, 85% of the green glass being collected on the East Coast is now being used as "alternate daily landfill cover." Another 15% is being used in non-bottle recycling applications such as roadbeds and other aggregates. In other regions of the country, glass is also being used to make fiberglass, but not yet in the Northeast, Martin said.

CRA is actively pursuing export markets for more than 30,000 tons of green glass sitting in its Northeast inventories. According to McAuliffe, CRA is exploring shipments to Italy, Spain, Portugal and France, despite European recycling subsidies that make it more difficult for Americans to compete there. Americans do benefit from low freight costs, however, as there is a surfeit of empty ships returning to Europe. CRA is also hoping to establish export outlets in South America. Chile and Argentina may hold promise as steady outlets for American exports of green cullet because they are large wine exporters. The value of the dollar will, to some extent, determine the viability of both export markets, McAuliffe said.

Contamination a continuing problem, but new technologies are helping

CRA's rejection rates for incoming glass loads are typically under 10%, they said, and are mainly due to contamination by ceramics; pieces of asphalt, stone or metal; and non-container glass such as broken Pyrex, windows, drinking glasses, and light bulbs. Liability concerns force bottle manufacturers to maintain high quality standards, McAuliffe said; they will reject a 25-ton truckload of cullet if three or four fingernail-sized pieces of non-container glass or refractory (non-burnable) material are visible. If small stones, or bits of china or non-container glass are accidentally incorporated into a furnace batch, they can cause catastrophic breakage of filled bottles, especially bottles with carbonated beverages under pressure, and hot packed jars containing soups and sauces.

Many people still do not understand which items are allowable at curbside and which are not, Martin said, and called upon recycling managers and educators to step up their consumer education efforts. Until then, CRA is meeting the contamination challenge head-on. According to Martin, CRA has invested $20 million in color sorting and ceramic detection equipment over the past five years. Using advanced German and Austrian camera technology, the new sorters can detect and reject rocks, metal and ceramic pieces, and can identify glass by color. The color profiles of scores of different glass types are stored in the computer's memory, and are referenced thousands of times per minute as pieces of glass ranging from a quarter of an inch up to two inches in size slide down the conveyor. Air jets operating at different pulse rates determine which bin the pieces are fired into: flint, amber, green, blue or reject.

With a throughput of up to seven tons per hour per machine, these laborsaving devices may eventually eliminate the costly sorting of glass at MRFs. They have already been in use for three to five years at CRA's plants in Chicago, California, and New Jersey. Two have recently come on line in Franklin, thanks in part to an equipment grant from the Massachusetts Department of Environmental Protection. According to Kerry and McAuliffe, this technology produces a higher quality cullet than traditional beneficiation does, and its use has led bottle manufacturers to "raise the bar." For example, they will now tolerate less than 2% color in a flint load.

The new machines can also identify and reject flint glass with painted labels containing cobalt compounds: Corona beer bottles, for example. Because these compounds can cause unwanted gray-green or blue streaking in molten flint glass, McAuliffe said, CRA is no longer accepting them; they are requiring MRF customers to segregate them before shipment. Corona is now the number one selling imported beer in the Northeast, he said, accounting for 50 tons of discarded bottles daily in the New York metropolitan area alone. Like green glass, these rejects must be used as landfill cover or in alternative, non-bottle applications.

These sophisticated automated sorting methods may become more important in the future if, as some analysts predict, more of the nation's curbside programs adopt "single-stream" collection, thereby generating a more heterogeneous (and contaminated) stream of recyclables.

The investment of millions of dollars in improved glass sorting technology becomes questionable, however, when one considers glass's shrinking market share relative to other packaging materials. Not only have most soda and juice bottlers switched over to PET (and to a lesser extent aseptic containers), but increasingly food bottles and jars, liquor, beer and even wine are phasing out of glass and into plastics. It remains to be seen whether glass--and glass recycling--will be with us to stay.

For more information, please visit the CRA website at

Reprinted with permission from the Northeast Recycling Council, Email Bulletin, September 1 issue and Jenny Gitlitz ( Jennifer Gitlitz is a Senior Research Associate with the Container Recycling Institute.

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