June 6th, 2012
Originally posted in GreenBlue's Blog, In The Loop
There are three primary ways to collect household recycling: single stream, source separation, and no separation from trash (or “all in one”). Each of these methods poses unique benefits and trade-offs. In the last ReLoop blog, we covered single-stream recycling. This month we take a closer look at source separated recycling.
Recycling is a process in which valuable materials flow from collection to an end user, who makes the materials into new products. This flow of materials is often called the recycling “stream.” In single-stream recycling, mixed recyclable materials travel together (separately from trash) in one stream to a sorting facility, or Material Recovery Facility (MRF).
Source separated recycling is “separating materials by type at the point of discard so they can be recycled.” For example, there may be separate streams of metal, glass, paper, and plastic; or there may be one stream for paper and one for mixed containers. Source separated recycling may also be called sorted stream recycling or dual stream recycling. These terms are used synonymously and all mean that the consumer sorts their recyclables.
Items collected may still go to a MRF for further sorting. For example, North Carolina has a network of “Dual Stream MRFs,” where two or more streams of recycling are fed separately into the facility. In this example, mixed paper is one stream and mixed containers are a second.
GreenBlue’s Source Separated Recycling Bins
The primary methods to collect source separated recycling are drop-off centers and curbside collection. In our office, we separate our recyclables into multiple bins, which are then taken to a local drop-off recycling center. At this drop-off, there are separate bins for each material. Our items are pre-sorted in the office, but sorting can also be done at the drop-off site if you bring a bin of mixed recyclables and hand sort them into the appropriate bins. These bins can then go directly to a buyer.
Source separated recycling can also be collected at curbside. Trucks collecting these materials have multiple chambers, one for each stream of materials. Programs may use multiple recycling bins or large carts with a center divider, creating two chambers. Materials are then dumped into the corresponding chamber. This contrasts to single-stream recycling, where the bin of mixed recyclables goes directly into a collection truck with no additional sorting.
Good – Materials from source separated recycling are generally higher in quality and can be sold at a higher price than materials collected as a single stream. There is also less potential contamination of recyclables (for example, left over liquids do not spill on paper and broken pieces of glass do not mix in with other items). Source separated recycling also does not rely as heavily on expensive sorting technology or manual labor.
Bad – Source separated recycling requires more effort by the consumer to either leave sorted items at their curb or take them to a drop-off site. In an area with a low recycling ethic, this can negatively impact participation in recycling, making collection volumes low.
The Grey Area – When it comes to recycling, many communities must make tough decisions between ease of use, quality of recyclables, and quantity of collection. Source separated requires more effort, but single stream (and all-in-one to a greater degree) results in more contamination, making a certain amount of materials unsuitable for sale and the processing of recyclables more difficult. Both programs require effective communication to consumers. Placing the wrong items in the recycling stream makes the materials less desirable, less valuable, and more difficult to manufacture into new products. Cost is another important factor in analyzing different types of recycling programs. The cost of a program is heavily dependent upon existing infrastructure, local markets for materials, and community goals.
We encourage you to explore your own recycling options, and let us know what you find!