Recycling Works

The newsletter of OWR's Recycling Business Assistance Center

Vol. 2, No. 2, April 1996

Index this issue . . .

Asphalt Shingles Reused in Road Pavement

By John Nelms, Market Development Specialist, RBAC

According to the 1995 update of The Assessment of the Recycling Industry and Recycling Materials in North Carolina, construction and demolition (C&D) wastes comprise almost 8 percent or about 721,000 tons of the waste stream. Of the total C&D tonnage, wood accounts for 30 percent, followed closely by asphalt shingles at 23 percent. The study projects that by 1997 nearly 174,000 tons of potentially recoverable asphalt shingles will be generated annually.

One of the most promising uses of recovered asphalt shingles is as an ingredient in road pavement. Asphalt shingle scrap, along with other tar-based materials such as tar paper and flat roof asphalt aggregate, can be processed into road paving mix. Scrap must first be ground and all nails and ferrous metals removed before it can be mixed with recovered asphalt and primary materials to form new paving mixes.

RBAC Work Group

To explore potential barriers to recovery and end uses for recovered asphalt shingles, the RBAC organized a work group of public and private sector representatives in the fall of 1995. Because shingles have been tested and incorporated into road pavement projects for many years in several states, road pavement emerged as the most promising use.

NCDOT Projects

In 1995, the NC Department of Transportation (NCDOT) utilized asphalt shingles in several pilot paving projects in the Raleigh area. The material for these projects came from CertainTeed Corporation, an asphalt shingle manufacturer in Oxford. CertainTeed has actively sought to reduce its waste stream since its waste shingle material accounted for nearly 40 percent of the Granville County landfill space in 1992.

The use of the asphalt shingles in the NCDOT projects was a result of a unique partnership. CertainTeed joined forces with Ross & Associates, a paving engineering firm, and C.C. Mangum, Inc., an asphalt paving contractor, to utilize asphalt shingles in hot mix asphalt paving. The goals of the group were to enhance pavement performance, reduce pavement costs, and eliminate the disposal of shingle material in landfills.

Additional Tests

At the present time, NCDOT has approved the use of post-industrial asphalt shingles at 5 percent of the hot pavement mix. While a shingle content of 5 percent has provided satisfactory performance, that proportion does not utilize the quantity necessary to make shingles an economically viable component. Ross & Associates estimates that favorable economies of scale can be achieved with an 8- to 10-percent shingle content. NCDOT, however, is requiring additional testing before authorizing the use of increased shingle content in specifications for asphalt paving mix. If the tests are favorable, DOT will use asphalt shingles in road construction projects.

Grant Awarded

The RBAC work group took steps to get the needed testing underway. Through a demonstration project award from the Solid Waste Management Trust Fund, Ross & Associates will oversee sophisticated performance testing on various shingle mixes. The National Center for Asphalt Technology at Auburn University will conduct the tests on mixes containing 0-, 5-, and 10-percent shingle material to determine the performance of each mix. Positive results from these tests should firmly establish the viability of asphalt shingle material in hot mix asphalt pavement in North Carolina.

Ben Ross of Ross & Associates says, "We feel confident that the results of these tests will be positive and that we will be able to continue to increase the use of asphalt shingles in road pavement mixes. This project will validate the use of shingle material as a viable alternative for the paving industry."

For more information please contact Ben Ross at 919-787-7070.

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Waste Not, Want Not: Woodbin2

By Bobbi Tousey, RBAC Manager

In 1993, building safety consultants Mike Krause and Bill Murdaugh became increasingly concerned about the quantity of waste piled in heaps around building sites. The two began brainstorming about collecting and reusing the material, and the formation of Woodbin2 was on its way.

Woodbin2 is a non-profit organization whose goal is to decrease construction wastes (primarily wood) through collection and sale of waste materials. The company donates any "profits" to Habitat for Humanity.

NCRA Support

Initial support came from the North Carolina Recycling Association, which helped secure grants to fund initial costs. Woodbin2 works closely with Habitat for Humanity and shares a warehouse and office space. According to Krause, "We take the materials we collect back to the Habitat warehouse, pull the nails, clean the wood if necessary, and sort and sell it as used wood. Our prices are about 60 percent of current retail and in some cases even lower." Woodbin2 also gathers concrete blocks from homes and sells them or gives them to Habitat for Humanity for use in its buildings.

Ambitious Plans

Although currently renting space from Habitat, Woodbin2 plans to expand the retail side of the company by adding a second outlet in the Cary or Garner areas. Plans for the future are ambitious and include working with volunteer "retired" people to train unemployed young people in the basic skills of carpentry.

"The shortage of carpenters and carpenter helpers in the framing and boxing crews throughout the booming Wake County housing industry is acute," said Krause.

He emphasizes that this training will create additional employment and help ease a labor shortage.

OWR Funding

Woodbin2 has requested funding from OWR to purchase a wood chipper, a truck, and a bagger in order to collect and sell smaller pieces of wood. "Currently, only wood 5 feet or longer is recovered and sold," said Murdaugh. "The wood chipper would allow us to gather every piece of scrap wood off the sites." The sale of wood chips as mulch will provide funds for continuing operations and expansion. In addition, the funds will be used to develop plans and instruction sheets for kits for building children's playhouses and dog houses.

100% Recycling

Woodbin2 has a goal of recycling 100 percent of the scrap materials generated in the building of a house. "This is a long-term goal. Markets must be developed, and a host of supporting projects must be planned and implemented," says Krause. "We're shooting to accomplish this total recycling by the year 2000, and we feel we're well on our way."

For more information, contact Mike Krause at 919-387-3366.

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How Can the RBAC Help You?

The North Carolina Recycling Business Assistance Center (RBAC) is a co-operative effort between the NC Department of Environmental, Health, and Natural Resources, and the NC Department of Commerce. Its mission is to promote environmentally sound economic development through the reuse and remanufacture of recyclable materials.

Who Can Benefit From RBAC Services?

RBAC offers a broad range of technical and business development assistance to existing businesses that wish to incorporate or expand the use of recycled material in their manufacturing processes and existing or new enterprises seeking to manufacture recycled-content products or explore innovative uses for recycled feedstock.

Types of RBAC Assistance

How Do I Get Assistance?

For assistance or more information, call the NC RBAC at (919) 715-6500.

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PETE and HDPE in Demand in North Carolina and its Border States

This is the second in a series of articles from "The Assessment of the Recycling Industry and Recyclable Materials in North Carolina - 1995 Update," which is also called the Market Assessment. Our thanks to Sandi M. Childs, Eastern Regional Director of the National Association for Plastic Container Recovery (NAPCOR), for her contributions to the PETE segments of this article.

Types and Uses of PETE

Polyethylene terephthalate (PETE) is used to manufacture a variety of products including durable and non-durable goods such as carpeting and film, packaging for soft drink and water bottles, and strapping. Because most of the PETE generated and recovered from the waste stream is made from rigid packaging, the Market Assessment focused on the generation and recovery of PETE containers. It should be noted that other PETE products such as carpeting and x-ray film are also being recovered for recycling.

Custom Containers

The fastest growing segment of the PETE industry in recent years has been the manufacture of non-soft drink or "custom" containers. These containers include PETE bottles for beverages such as sports drinks, personal care and cleaning products, edible oils, and condiments. While custom containers are as recyclable as soft drink bottles, there is a misconception that they are made from a different "grade" or "type" of resin. Some material recovery facilities (MRFs) are hesitant to accept custom PETE bottles because of the belief that they must be handled separately or sold to different markets.

According to the National Association for Plastic Container Recovery (NAPCOR), however, there is no difference between the PETE resin used for soft drinks and custom bottles. While there may be a slight variation in the resin to account for different bottle shapes, sizes, and contents, these variations are so slight as to be virtually insignificant. As recycling programs become aware of the recyclability of "custom" containers and include custom PETE collection in their programs, they may increase the quantity of PETE recovered by as much as 25 percent.

Types and Uses of HDPE

High density polyethylene (HDPE), one of the most common plastic resins, is used to manufacture a wide variety of products. In its annual review, Modern Plastics reported that approximately 5.1 million tons of HDPE resin were used to produce goods in the U.S. in 1994. Approximately half the resin generated in 1993 was used for items such as blow-molded milk and water bottles, injection-molded crates and tubs, and extruded films for bags and wraps to produce packaging. Other products commonly made from HDPE include extruded plastic pipe and insulation on wire and cables.

Although some durable HDPE products and HDPE film are being recovered, most of this recovery is a result of container collection. Thus, the Market Assessment estimated the generation and recovery of rigid plastic containers. The most common HDPE products recovered from the waste stream are milk and water jugs manufactured from natural blow-molding grade resin; fewer pigmented HDPE bottles are recovered. One kind of HDPE containers not recovered in significant amounts are injection-molded rigid containers such as margarine tubs. Although this material is sometimes recycled through mixed plastic recovery programs, those programs are few in number.

PETE and HDPE Container Generation

In a report prepared for Keep America Beautiful ("The Role of Recycling in Integrated Solid Waste Management," September 1994), Franklin Associates, Ltd., gave estimates for the amount of PETE and HDPE bottles generated in the U.S. waste stream in 1992 and 2000. It was estimated that by 2000, PETE bottle generation would increase from 760,000 tons in 1992 to approximately 1,200,000 tons; and the 1,215,000 tons of HDPE bottles that were generated in 1992 would increase to 1,500,000. Generation estimates for North Carolina and its border states were developed by prorating U.S. estimates by population.

PETE and HDPE Container Recovery

According to a study commissioned by NAPCOR, the 1994 U.S. recycling rate for PETE bottles was 34 percent, which represents 565 million pounds of PETE recycled. (The NC Market Assessment reported that approximately 540 million pounds of PETE were recovered in 1994). The NAPCOR study measured a true recycling rate rather than a recovery rate since it measured pounds of PETE flake produced by reclaimers that buy bales from MRFs and perform the grinding, and sometimes cleaning, that end-use markets require.

The amount of PETE and HDPE containers recovered from North Carolina and its border states was estimated by prorating the U.S. recovery estimates with the region's population having access to curbside collection recycling programs. Although these programs are not the only recovery methods for PETE and HDPE in the U.S., access to curbside programs does provide an indication of plastic collection infrastructure in the region relative to the rest of the country.

According to information compiled by the Office of Waste Reduction for fiscal year 1993-94, North Carolina had an estimated recovery rate of approximately 23 percent of PETE containers and 12 percent of HDPE containers. Using the prorating procedure described above, recovery rates for North Carolina and its border states were estimated at 17 percent for PETE and 10 percent for HDPE . Projected recovery rates for North Carolina and its border states for 1997 and 2001 are 19 percent and 21 percent for PETE, and 11 percent and 13 percent for HDPE, respectively.

Demand Estimates for PETE

Over the past few years, the capacity for processing and using recycled PETE has expanded significantly. Both the intermediate processing and the end-use markets for PETE in North Carolina and its border states are strong and stable. Demand for post-consumer PETE is expected to increase through the remainder of the decade, but industry estimates of U.S. demand by the year 2000 vary, ranging from 635 million pounds to 1,400 million pounds.

Conservative annual increases for fibers, bottles, and strapping of 10 percent, 14 percent, and 25 percent, respectively, were applied to the figures for current PETE consumption in the region to estimate demand for 1997 and 2001.

Because local processing capacity exceeds the local supply and major markets for recovered PETE are located in the Southeastern U.S., the Market Assessment concludes that recycling programs in North Carolina should investigate opportunities for recovering more PETE from the waste stream by collecting custom PETE containers in addition to PETE bottles.

According to Gary Pratt, President of P&R Environmental Industries, Inc., which receives plastic bottles from all over the East Coast, "Our machines can process 'custom' PETE as readily as soda bottles. We would welcome more 'custom' PETE from any North Carolina Recycling Program."

Demand Estimates for HDPE

As is the case with PETE, demand for post-consumer HDPE is expected to increase through the remainder of the decade, but industry estimates for U.S. demand by the year 2000 vary; they range from 967 million pounds to 3,050 million pounds.

Conservative annual increases for pipe (10 percent), film (10 percent), lumber/pallets (20 percent), and containers (10 percent) were applied to the figures for current HDPE consumption in the region to estimate demand for 1997 and 2001. The Assessment noted that although fewer pigmented than natural-colored HDPE bottles are recovered, the regional market is significantly larger for colored HDPE than for natural HDPE.

PETE and HDPE - Supply/Demand Relationships

Based on recovery rates of 17 percent, 19 percent and 21 percent for PETE in 1994, 1997, and 2001, respectively; and recovery rates of 10 percent, 11 percent, and 13 percent for HDPE in 1994, 1997, and 2001, respectively, the table below outlines the theoretical supply and demand for PETE and HDPE containers in North Carolina and its border states. It should be noted that recovery rates for North Carolina alone are estimated to be significantly higher for PETE and slightly higher for HDPE.

Summary of Supply and Demand Estimates for North Carolina and its Border States (thousand tons)

1994 1997 2001
Material Supply Demand Supply Demand Supply Demand
PETE 17 288 22 385 30 566
HDPE 14 32 17 44 22 70

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For assistance with source reduction, reuse, and recycling and general waste management concerns, contact the NC Office of Waste Reduction at (919) 715-6500 or E-Mail

The Office of Waste Reduction provides free, non-regulatory technical assistance on methods to eliminate, reduce, or recycle wastes before they become pollutants or require disposal.

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