Inside a Single-Stream MRF

Want to see what single stream can be when it’s working well? Then take a tour of Recycle America Alliance’s material recovery facility in Grayslake, Ill.

By Robert L. Reid

   Is single-stream collection “the beginning of the end” of successful recycling, especially for recovered fiber, as one paper mill critic warned this year at a recycling conference? Or is it a way to both increase fiber recovery and help municipalities keep their recycling programs by making curbside collection economical, as a single-stream supporter countered?
   The proof, of course, is in the paper, which is why Brian Fielkow, a vice president of Recycle America Alliance (and the single-stream supporter mentioned above), isn’t shy about inviting potential customers, critics, students, and the just-plain-curious to visit one of his company’s newest, state-of-the-art single-stream facilities.
   “See it with your own eyes,” Fielkow says of the company’s Grayslake, Ill., material recovery facility (MRF), which collects recyclables from communities north and northwest of Chicago. Scrap took Fielkow up on his offer in September to gain what he describes as “a firsthand feel for our vision of what single stream can be when it’s working well.”

Switching to Single Stream 
In single-stream collection systems, residential recyclables such as paper and aluminum, steel, glass, and plastic containers are commingled in a single bin. While this approach reportedly makes recycling easier for citizens and expedites the collection process, some paper mills complain that single stream leads to excessive amounts of prohibitives and outthrows—that is, contaminants—in the recovered fiber.
   Yet Recycle America says it sells every pound of fiber it collects at Grayslake and its similar single-stream MRFs—at market prices. Moreover, though most of the Grayslake fiber is a No. 8 ONP exported to China, “we do sell a small percentage of our No. 8 to a domestic mill, and that domestic mill has asked us for more,” says Donald Schmidt, Grayslake’s plant manager. “That’s the best testimony I can get.”
   The Grayslake MRF started out as a dual-stream operation, built by Waste Management Inc., Recycle America’s parent company, in 1997 for about $4.3 million, Schmidt says. The plant converted to single-stream processing in March 2002, following an additional $4.5-million equipment upgrade. The switch came about because three of the largest communities served by Grayslake—which collects material from some 300,000 households throughout Illinois’ Lake County and nearby regions—wanted to “enhance their recycling programs, so they approached us about the best way they could get more participation,” explains Schmidt.
   These communities had been using the traditional blue box-style recycling bin, an open container with an 18-gallon capacity, that was sorted at the curb by Waste Management or other hauling company employees into the fiber and container sides of the trucks, Schmidt describes. The first idea was simply to switch from blue-box bins to covered 64-gallon carts, which have increased participation in other areas. Such carts are bulky and can be difficult to service, Schmidt says, so the best approach seemed to be switching to the larger carts while simultaneously changing to single-stream collection, thus saving the sorting tasks until the material is dumped at the MRF.
   A pilot program in August 2001 convinced Recycle America that single stream would work at the Grayslake MRF. Soon thereafter—on the terribly memorable date of Sept. 11, 2001—the company signed the contracts with equipment producer CP Manufacturing Inc. (National City, Calif.) to modify the facility’s operations to single-stream processing. New conveyors and screening equipment represented the bulk of the upgrade, with most of the machinery customized to meet Grayslake’s needs.
   Notably, Grayslake allotted just six weeks—from the end of January 2002 until about the second week of March—for the actual installation. Though this work began even before the roof was entirely in place on the 15,000-square-foot addition (which brought the total facility up to more than 45,000 square feet), CP kept to the schedule, Schmidt says. Also, though a Grayslake manager probably set a record with CP for the number of redraws to the plans, such preliminary work resulted in “zero change orders that cost any money,” he notes.
   During the renovation, Grayslake’s material had to be shipped to another Recycle America facility, adding to the urgency to get the job down. In the end, the MRF reopened for business as a single-stream operation just two days after its target completion date.

A Thousand Homes a Day
Originally, Grayslake expected to collect the new 64-gallon carts every other week. The public response to single stream was so positive, however—at least a 30-percent increase in material per resident—that the MRF continues to collect recyclables on a weekly basis, Schmidt says. Beyond the additional material, single stream also expanded the number of homes the company could service each day and the types of trucks it could use to collect the material.
When Waste Management first started collecting recyclables in the Lake County region in 1991—before the Grayslake plant was even built—the company used special trucks with more than a half-dozen compartments to sort various commodities at the curb, Schmidt says. These trucks could service only 250 to 300 homes a day. When the Grayslake MRF opened as a dual-stream facility in 1997, the company switched to trucks with two compartments—one for fiber, one for containers—and collections increased to as many as 700 homes a day.
   Now that Grayslake is accepting single-stream material, however, drivers can pick up from nearly 1,000 homes a day, using a variety of vehicles, many with automatic tipping equipment. 
   “With single stream, we can utilize any kind of truck, from a 100-yard transfer trailer to a regular garbage truck to a front-end loader or side loader—we’re using all kinds now,” Schmidt notes.
   Waste Management’s hauling division handles most of the pickups for Grayslake. About 27 percent is also delivered to the site by independent haulers and even competing recyclers, Schmidt says. Switching to single stream enabled the hauling division to eliminate at least two and possibly three of its trucks, he adds, “which is rather substantial when you figure that the trucks cost almost $200,000 each.”

Following the Fiber
When trucks arrive at Grayslake, they get weighed and then dump their material on either the residential single-stream or commercial tipping floor (which accounts for just 8 percent of the facility’s tonnage). The composition of the material is 70 percent recovered fiber and 30 percent rigid household containers, Schmidt says. Within the fiber portion, No. 8 ONP is the leading commodity, accounting for 70 percent of the fiber, followed by smaller percentages of mixed paper, No. 6 ONP, and OCC.
   From the tipping floors, material is pushed onto conveyors that carry it up to the presort area. Here, sorters pick out obvious residue and refuse and even rip open and empty the plastic bags that various communities permit residents to use for their bottles and cans, Schmidt says. The bags themselves are collected and baled for a consumer that makes plastic lumber, he notes, but the rejects are picked off the line and dropped through chutes to another conveyor that feeds two trash compactors. When one compactor is full, Schmidt explains, the conveyor automatically shuttles rejected material over to the other.
   From this presort area, the mixed recyclables move up another conveyor to the first mechanical sorting system, an OCC screen from CP that uses a series of rapidly rotating scalloped steel discs to send the big pieces of corrugated up and over to drop onto a conveyor belt that carries the material to a storage bunker. Once the bunker is full, the OCC can be fed along an extension conveyor to the main baler conveyor belt.
   Many single-stream operations sort corrugated manually, Schmidt notes, but Grayslake opted for mechanical sorting for both the residential and commercial OCC, which helped the facility eliminate three to four sorters per line. Switching to single stream also eliminated the need to sort glass—which Grayslake had done as a dual-stream operation—largely because all the mechanical screens now break any bottles or jars. That also reduced the need for hand sorting at one stage, Schmidt notes, though the facility simultaneously added sorters to other parts of the fiber lines.
   Recovered fiber other than OCC and containers that dropped out of the OCC screen now travel up a conveyor to the CP news screen, which is similar to the OCC screen except that it uses scalloped rubber discs to separate the larger, flatter pieces of newsprint. Material is then split to an upper and lower conveyor, for sorting of No. 8 ONP, while No. 6 ONP, OCC, and other fiber drops into bunkers to be baled. The lower ONP sorting line was part of the original dual-stream operation using Machinex equipment, Schmidt notes, but the upper line was added by CP to help the MRF meet its goal of processing 30 tons of material an hour. 
   Both ONP lines use a negative sort, leaving the desired fiber on the conveyor while pulling off the aluminum cans, plastic containers, and other nonfibrous material. The newsprint then drops into one of two “live floor bunkers,” which means they have conveyors to carry the material to the facility’s two Lindemann balers.
   Fiber that wasn’t diverted to the newsprint sorting lines then passes with containers over another CP screen that Schmidt describes as a “cleaning” screen. This final screen uses fatter rubber discs than the news screen to “scarf off the last grade of paper” from the containers, producing a hard-mixed paper product from things like envelopes, junk mail, and chipboard. This line also sends the paper to a bunker before baling.

Conveying Containers
Plastic, aluminum, and steel containers that remained on the conveyor after the cleaning screen now drop onto an inclined belt that carries them to a presort area of their own. Other containers that were sorted out along the way have also been conveyed to this point. Here, a sorter tries to pick out any remaining fiber before the containers move into a trommel magnet, a large rotating drum with small holes in it to sift out the broken glass and dirt, which drop onto a conveyor and get sent to the mixed broken glass bunker. 
   Leaving the trommel, steel cans are grabbed by a magnet and sent to the conveyor for ferrous recovery, while the light containers—UBCs and plastics—are blown by an air classifier onto a belt that feeds into a perforator-flattener to make these products easier to bale, Schmidt notes. Sorters then separate the plastics into three grades: HDPE natural milk jugs; PET soda bottles; and HDPE color, such as detergent bottles. 
   Another sorter gives the material one last look for fiber before the stream passes through an eddy-current separator to toss UBCs into their own bunker. The UBC bunker is then gravity-fed to a conveyor that carries the nonferrous material past four final sorters to make sure the aluminum cans are as clean as possible, Schmidt notes.

Meeting Market Specs
At Grayslake, the combination of modern screening technology and various teams of hand sorters enables the MRF to turn commingled single-stream material into quality commodities, Schmidt asserts. Though Recycle America won’t discuss actual numbers for fiber contamination, the company does state: “We can unconditionally say that Grayslake is currently meeting all mill specs that we ship to.” 
   Most of those mills are in China, which consumes some 95 percent of the MRF’s recovered fiber. To help ensure that it makes a quality package, therefore, Grayslake welcomes a daily inspection by the China National Import and Export Commodities Inspection Corp. (CCIC), China’s export agency. While there have been occasional downgrades due to moisture or outthrows, “we’ve never had an export load rejected in five and a half years,” Schmidt says, a period which covers most of the MRF’s dual-stream operations and now its single-stream production. Moreover, he adds, the Chinese inspector said “he noticed an improvement in the fiber after our switch to single stream.”
   Other major consumers for the MRF’s baled scrap include various locations of Anheuser-Busch Recycling Corp. for UBCs; Alabama-based K.W. Plastics for plastic bottles; a California plant of Boise Cascade Corp. for plastic bags; and Indiana-based OmniSource Corp. for steel scrap. In addition, Container Recycling Alliance in Chicago, another Recycle America division, optically sorts and sells the MRF’s loose broken glass.

Award-Winning Education
An educated community is one key to achieving quality single-stream material, states Schmidt. To that end, Grayslake sends out fliers to inform homeowners about what should and should not be included in their single-stream containers (hint: no plastic swimming pools or basketballs), as well as where to put the carts (at the curb, not in the alleys that run behind some homes). Haulers are also instructed to leave notes if a homeowner hasn’t followed procedures. Plus, the MRF opens itself up for tours by groups from students and scouts to local businesses and even visiting recycling professionals.
   A central part of those tours is a visit to Grayslake’s EduCycle Center, a classroom-like setting attached to the MRF’s offices that displays information on recycling and features closed-circuit television access to the plant’s tipping floors, sorting lines, and processing areas.
   Some 7,000 visitors a year come to the EduCycle Center, which also displays products made from recycled materials, such as T-shirts made from old soda bottles, notes Kruti Patel, coordinator. While school kids often want to know how recycled products are made, adults seem to want confirmation that recycling programs actually work. “When they see the plant,” Patel says, “I think they walk away knowing that, yes, things really are being recycled.”
Both Patel and the MRF itself were honored this year by the recycling division of the Illinois EPA for their recycling efforts, with Patel named “outstanding educator of the year” and Grayslake named “outstanding recycling facility.”

The Long Haul
   Within Recycle America, Grayslake is one of 15 single-stream facilities out of the company’s more than 80 MRFs nationwide. In addition to being one of the firm’s newest facilities, it is one of the largest, with throughput of about 13,000 tons a month.
   While Recycle America intends to meet the needs of the communities it serves—whether they want single-stream, dual-stream, or some other kind of collections—the company also believes that single stream “is where a lot of the market is going, especially as people focus more and more on costs,” notes Brian Fielkow. “Single stream creates tremendous collection efficiencies for municipalities and for anybody collecting. In addition, it creates much more user-friendly programs for residents, so they can spend less time thinking about recycling and more time doing it.”
   Single stream is both reducing hauling costs for Grayslake and increasing processing costs, reports Recycle America, which won’t disclose exact numbers. But those additional expenses should be viewed from the proper perspective, says Fielkow. 
   “Running a ton of single stream certainly involves more than baling a ton of clean corrugated,” he notes. “But you can’t look at just one piece of the equation, you’ve got to look at the whole thing and weigh the efficiencies of the program overall.”
   Though Fielkow acknowledges that some earlier single-stream plants definitely had quality problems, he stresses that Grayslake represents about the sixth generation of single-stream MRF development. “Like any innovation, you’re going to have varying degrees of success, with more and more success as you grow and perfect the process,” he says. Overall, he adds, Recycle America is retrofitting some of its earlier single-stream plants and plans to grow single stream in the markets where the communities are willing partners.
   While single stream may always have its critics, Fielkow concludes: “The debate over single stream is healthy, but the reality is that it’s here to stay. The question is: How do we work together to make it best for everybody? We’re not saying that from its inception, single stream has been perfect—but it’s getting much, much better, and we’re in this for the long haul.” 

Robert L. Reid is managing editor of Scrap. •