Dual Stream Recycling
Strengths & WeaknessesWhy We Chose
To understand why Emmet County chose a dual-stream recycling system (separating recyclables into two different groups), let’s start with a look at the alternatives. We begin with what residents and businesses are asked to do with their recyclables under each kind of system:
- Sort them into numerous bins (typically drop-site recycling only in North America)
This is called a “Source-Separated” system and is what we offered at Emmet County Recycling Drop Sites until 2010. There were seven categories here, such as glass, plastics, newspapers, etc.
- Sort them into two groups of materials
This is called a “Dual-Stream” system and is what is now in place in Emmet County. Our two groups are “Paper, Boxes and Bags” and “Mixed Containers,” with the latter including steel, glass, plastic, paper carton/cup, and aluminum containers.
- Put them all in one bin
This is called a “Single-Stream” system. Glass is often excluded from these programs so it doesn’t contaminate paper. Sometimes so-called single-stream programs collect glass separately.
- Nothing special: Put them all in the garbage
Typically everything put the garbage ends up buried in a landfill or incinerated. In the very few areas of the country where recyclables are removed from the garbage, it is a called a “Dirty-MRF*” system. Garbage, as collected from homes and businesses, is sorted with recycling equipment and by hand to recover some of the recyclables.
This seemingly simple distinction has huge ramifications down the line in terms of cost to operate the recycling program, the quality of the resulting materials, and their value.
In general, in the waste and recycling industry there has been a huge movement away from source-separated systems, because they are inconvenient for residents and businesses and, where bins are divided to keep multiple materials separate, they don’t fill evenly which makes collection inefficient. Both dual-stream and single-stream systems are common, and there has been a push by private waste haulers to go to single-stream systems.
Strengths and Weaknesses of Recycling System Types
While performance of different recycling programs using similar systems varies greatly, in general it is agreed in the recycling and waste industry that the strengths and weaknesses of the four systems are as follows.
|Materials collected and received by processing facility
||As many separate groups
||As two groups
||All recyclables together
|Convenience for residents/businesses
|Sorting equipment expense
|Worker exposure to biohazards
|Amount of recyclable material lost due to inaccurate sorting or contamination
|Quality of resulting materials
|Markets for resulting materials
|Market value of resulting materials
|Preferred by waste haulers
|Preferred by factories which buy recyclables
Why We Chose Dual-Stream Recycling
Cleaner Stocks for Factories
Materials collected in two “streams” stay cleaner, which is critical for most manufacturers.
As you’d imagine, some people don’t rinse out their containers. So when–in single stream systems–the containers are mixed in with the paper and cardboard, liquids contaminate the paper and cardboard. Think spoiled milk and orange juice soaking newspapers. The Dirty MRF model is a whole other can of worms. Recyclables recovered from garbage can be contaminated with all of the nastiest and most toxic things people and busineses throw away. Sometimes materials from single-stream or dirty MRF systems are so dirty that insects infest the bales. Most manufacturers simply can’t use paper or cardboard contaminated with liquids, glass, pests or garbage.
Highest and Best Use
All uses for a given recyclable material are not created equal. By producing clean dual-stream recyclables, Emmet County is able to market your recyclables for higher and better uses.
The following simplified hierarchy of highest and best use can be applied to any material:
- Reduce waste
- Reuse (use reusable items instead of disposable, for example coffee cups)
- Bury in landfill or burn in an incinerator
Take office paper for example. A community could
- Promote reduced use, and thereby waste, of office paper for example with “paperless office” campaigns
- Encourage reuse of paper, for example using it as scrap paper
- Recycle it and sell it to a factory which will make it into new office paper
- Recycle it and sell it to a factory which will make it into paper towels
- Compost it
- Bury it in a landfill or burn it in an incinerator
If it is made into new office paper, after it is used (and hopefully reused) then discarded, it can be recycled again. If it is made into paper towels, then when it is used and discarded it can no longer be recycled into another paper product, but it could be composted. Or buried or burned.
Composting, burial, and burning clearly preclude the paper being recycled again. However, if composted, it can contribute to gardens, landscapes, or agriculture. When burned it may (if dry enough) produce some energy, but not nearly as much as would have been saved by recycling it. And burning it is polluting. Landfilled, it will eventually break down, producing methane and contributing to the greenhouse gases generated by landfills.
So recycling it for office paper is the highest and best recycling use, with recycling into paper towels second, and composting a distant third. But office paper contaminated with liquids, glass, and garbage cannot be recycled. It may not even be appropriate to compost.
By producing cleaner recyclables, dual stream allows us to supply more Michigan companies than single-stream systems can.
Most manufacturers can’t use recyclables that are contaminated with liquids and more than 5 percent of material other than what they’re buying. Because our dual-stream system and excellent sorting produce “clean” recyclables, we can serve Michigan companies that single-stream recyclers and dirty MRFs can’t. The result? In 2012 over 97% of the materials recycled by the Emmet County Recycling Center supplied Michigan businesses.
Jobs for Michigan
By producing clean recyclables which we can sell to Michigan companies, we keep more money and jobs in Michigan.
Supplying Michigan businesses keeps more of the economic benefits of northern Michigan’s recycling in Michigan! Manufacturers can buy our recyclables for less than it costs them to purchase virgin inputs for their products. This helps Michigan businesses be more competitive in our global economy, thrive and employ more people!
Cleaner feed stocks require less energy to prepare them for the final manufacturing processes. Also, by producing clean recyclables which we can sell to Michigan companies, our recycling program achieves greater energy savings than would be realized by hauling materials out of state.
Much of the energy used in manufacturing is used to purify and convert raw materials. Recycling in general cuts these processes down dramatically, because recyclables have already been refined from the raw materials extracted from nature. Even less preprocessing is required when starting from the cleanest recycled materials. Also, keeping distances recyclables are transported down maximizes energy saved by recycling, though research shows that even when recyclables are hauled long distances—even to China—there are still substantial energy savings from recycling. Saving energy has numerous benefits, including conserving supplies for the future, saving money, reducing climate disruption, and preventing pollution.
Funding Recycling without Tax Dollars
Brokers and factories pay much more for cleaner materials, helping to fund the Recycling Center without tax dollars. We are also able to share the benefits with our partner counties (Cheboygan, Otsego and Presque Isle), with private waste haulers, and with businesses with particularly large volumes of a given material.
The value of cleaner materials really shows in the market place: Emmet County’s clean recyclables commonly sell for double, triple, or even four times as much as single-stream recyclables.
You Rock It!
Proponents argue that single-stream increases participation in communities with weak recycling. Maybe. However here, you–and over 80% of your neighbors–are recycling huge quantities of high quality recyclables dual stream.
Some communities with weak participation have seen impressive increases when they went to single-stream recycling. However researchers question whether it was getting to mix everything together that made the difference. You see, at the same time, these programs also made recycling more convenient, for example delivering containers to people who didn’t already have one for their recyclables and providing containers which are larger and easier to use. These communities may have begun accepting new materials at the same time as going to single stream as well. If you’d like to read more about research on dual v. single stream recycling click on the PDF at the end of this section.
But even if the single-stream proponents were right about it increasing recycling, participation is NOT weak here! Emmet County residents are already huge recyclers: In areas of the county which don’t have curbside recycling, over 80% of households recycle. Participation is even higher in the curbside communities! You rock both the quantity and the quality!