Limiting Contamination in Single-Stream Recycling (with related video)

Limiting Contamination in Single-Stream Recycling (with related video)

Metro Waste Authority in Iowa implements single-stream recycling and minimizes contamination.

Since its arrival on the scene more than 20 years ago, the advocates of single-stream recycling have touted its benefits: reduced collection costs and worker’s compensation costs, and an increase in the amount of recyclables collected. However, single-stream recycling also has produced complaints about contaminated recyclables that result in less usable material for end markets.

More than one industry observer says that contamination can affect any recycling method — multi-stream or single stream. “The fact is, you can have contamination with dual stream recycling or single stream recycling when the materials are mishandled,” says Lisa Skumatz, a principal with Superior, Colo.-based Skumatz Economic Research Associates, a research and consulting firm. “Adding steps at the end of a MRF (material recovery facility) process will reduce contamination. Slower processing feeds on the belts will lessen contamination too. So will increased management attention to public education.”

When the Metro Waste Authority (MWA), which provides waste management services across central Iowa, decided to implement its single-stream collection program, it was familiar with the contamination issue and determined to minimize it through aggressive public education and by requiring the latest MRF sorting technology.

The Conversion Begins

MWA services 22 communities and 75,000 households in the Des Moines metropolitan area. In 2008, as MWA’s collection and processing contracts were expiring, officials decided to replace the existing five-sort recycling program with a single-stream system. “We wanted to make a change because we were seeing a steady decline in increased recycling tonnage,” says Reo Menning, public affairs director with MWA. “The totals were still increasing but only by very small amounts. Surveys also showed general dissatisfaction with sorting and managing five 18-gallon bins.”

In evaluating the contamination issue before committing to the change, authority officials concluded that today’s automated single-stream sorting technology could overcome the problem. “We had been monitoring the technology that processes single-stream materials and believed that it had advanced to the point where you could sort and sell [the recyclables] for a pretty good price,” Menning says.

According to a report authored by Menning and presented at WASTECON 2010, the selection process produced three well-known vendors. Waste Management of Iowa Inc. would handle collections, Houston-based Greenstar Recycling would process the recyclables at its area single-stream MRF and Toter of Statesville, N.C., would supply the 48-gallon and 96-gallon carts. Some of Greenstar’s appeal to MWA was its familiarity with handling glass. The company handles bottle redemptions — Iowa is a bottle bill state — and is skilled with glass-handling technologies. To secure the contract, Greenstar committed to a multi-million dollar upgrade of its Des Moines MRF to ensure the quality of the processed materials. The cost of the upgrade posed an economic challenge: it would take much more than the recycling volumes supplied by MWA’s 75,000 households to support the investment. To solve that problem, the city of Des Moines decided to throw in with MWA and add its 65,000 households to the program.

The Campaign

In addition to Greenstar’s advanced technology contamination-management effort, MWA carried out an aggressive public education campaign directed at the 140,000 households in MWA’s communities and Des Moines. Among other things, the campaign educated residents on what materials they could and could not place in the collection bins. In all, the campaign cost about $340,000 — about $2.45 per household.

MWA brought in the advertising firm Trilix Group of Johnston, Iowa, to help with the campaign. The firm created the tagline “Curb It! Recycle and Roll,” radio advertisements and a website promoting the single-stream program. In January 2009, fliers carrying the program’s tagline and logo went out to residents. The authority set up booths at local home shows and other events to display the carts, pass out literature and answer questions. News releases also spawned coverage by the media.

MWA representatives visited the city halls in each of its 22 communities, provided one-page summaries of the program and encouraged the staff to direct residents with questions to MWA.

A second wave of public education preceded the delivery of carts and focused on how to use the carts. This phase consisted primarily of radio and print advertising as well as information in community newsletters and on community websites.

When the carts were delivered, they arrived with a customized piece of literature noting the first date each house could set out the cart and how to figure out the bi-weekly collection dates from then on. The flyer listed what materials could be put in the cart, while a sticker on the cart illustrated those materials. Still another educational effort distributed written materials explaining to residents how they should set out their carts for the automated collection trucks.

The Results

Finally, in July 2009, single-stream recycling got underway in central Iowa.
In the first month, participation rates reached 96 percent. Most encouragingly, MWA officials say the education program and the MRF technology handled the contamination problem.

In recent years, some single-stream recycling programs have reported residues — materials that cannot be recycled — as high as 13 to 20 percent, according to Reo Menning’s WASTECON 2010 report. After one year, MWA’s residues were running at 3 percent (the previous five-sort system logged a residue rate of 1 percent), and the volume of recyclables collected had increased 20 percent.

Furthermore, the fees paid by MWA for recycling collections declined by more than $300,000 in the first year of single-stream when compared with the last year of the five-sort program, a result of the use of automated trucks, which reduced crew size, and the move from weekly to bi-weekly collection.

Certainly the fact that Iowa is a bottle bill state, which results in residents placing less glass out for curbside collection, helps lower the contamination rate, but observers say that public education and advanced MRF technology will work to reduce contamination to acceptable levels in non-bottle bill states as well.

The Broad Outlook

Other communities are joining MWA and taking the single-stream plunge. According to “Single Stream Recycling Collection Alternatives,” a 2008 report by Long Beach, Calif.-based SCS Engineers, the number of single-stream MRFs nationwide grew from 10 in 1995 to more than 160 in 2007. Dozens more have come on line since.

“Single stream is for real,” says Michael E. Hoffman, managing director and director of research with the Baltimore office of Memphis-based Wunderlich Securities. “Just look at the math. Landfill tipping fees average $40 per ton at a 16 percent margin. Labor intensive, dual-stream MRFs process a recycling ton for between $65 and $80 per ton, $25 to $40 per ton more than landfilling.”

Today, the average price paid for paper by mills ranges from $80 to $100 per ton, Hoffman continues. The cost per ton of dual stream processing is too much to allow a comfortable profit margin, he adds.

Single stream recycling increases the amount of recycling collected — including high-priced paper. “With more volume to process, you can afford capital-intensive, single-stream processing technology that reduces labor requirements,” Hoffman says. “Automation reduces processing costs to about $55 per ton. If I sell a ton of paper for $100, there will be a $45 profit, which I will split with the municipality and still have a $20 to $25 profit.”

The point, according to Hoffman, is that the largest companies in the industry are lining up to build single-stream recycling portfolios. “They are talking to their municipal customers, recommending single-stream recycling and making capital commitments to build single-stream MRFs,” he says.

The coming move to single-stream recycling could make the explosion in single-stream seen in recent years look modest. “As this runs its course, I think there will be consequences,” Hoffman says. “There are a lot of small- and medium-sized companies that will have to think about building single-stream MRFs. Some won’t have access to capital. Those who do have capital may not want to risk it. The alternative would be to sell to a larger competitor. So as single-stream processing matures, it may fuel a new wave of consolidation in the waste industry.”

Michael Fickes is a Westminster, Md.-based contributing writer.


The Six Worst Recycling Contaminants of the Curb It! Program (from MWA's YouTube Channel)

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