Dual Stream Recycling

Dual Stream Recycling Offers Benefit of Less Contamination

Recycling sorted
••• Fuse/Getty Images

As contamination and inefficiency problems associated with single stream recycling become more apparent, a dual stream approach is being increasingly considered as an alternative. Dual stream recycling requires consumers or depositors to pre-sort the recyclables before putting the materials into the curbside recycling bins. As the name suggests, materials are divided into two categories: mixed containers and paper boxes and bags.

So, under the dual stream recycling system, there will always have two separate containers to put the materials; one for mixed containers and the other for paper boxes and bags. The materials are collected by two separate trucks or by a single truck with two sections to keep two streams separated.

Advantages of Dual Stream Recycling

Single Stream Recycling and Multi-stream Recycling are other two types of recycling systems. Under single stream recycling, consumers are not required to pre-sort the materials and can simply put everything that is not trash into a single bin. Under Multi-stream Recycling, consumers are required to pre-sort the recyclable materials into multiple categories and put the right kind of materials into the correct bins. There are advantages and disadvantages from the perspectives of both consumers and recyclers in single and multiple stream recycling systems. Dual Stream Recycling is something in between single and multi-stream recycling systems.

The major advantages of dual stream recycling are:-

Lower Levels of Contaminations: Under single stream recycling, the levels of contamination of collected materials are relatively higher as all the materials are put into a single bin. But under dual stream recycling system, as the materials are pre-sort, the quality of materials recovered is relatively better.

Moderate Collection Costs: Collection costs is highest under multi-stream recycling system as a good number of collection bins must be placed to allow consumers to put all the different kinds of materials into different bins. Again, under single stream recycling, the collection costs is lowest as the number of bins required to be placed is lower. So, the collection cost under dual stream recycling is moderate as it requires two collection containers placed at each collection point.

Lower Processing Cost: As the level of contamination under dual stream recycling system is lower and materials are pre-sort, the cost of processing is lower. It takes lesser energy and manpower to sort the materials and make bales for separate materials.

Disadvantages of Dual Stream Recycling

Lower Public Convenience and Participation: Proponents of single stream recycling argues that single stream recycling offers better public convenience and increase participation as the residents are not required to pre-sort the materials. They can simply put everything that is not trash into a single bin. Under dual stream recycling system, surely the public convenience is comparatively lower but the rate of participation can vary.

But the general understanding is that due to lower convenience, the public participation too is lower. Putting materials into two separate bins should not be called inconvenient for consumers as it should not take more than a minute to separate all kinds of containers from the paper or paper boxes.

Single-stream Versus Dual Stream Recycling

Research has been done in this field but no consistent body of research could demonstrate definitively that either single or dual stream recycling is a specific best practice. A research project was conducted in Florida based on solid waste management data of different counties in Florida from 1996 to 2012.   

No conclusive decision has been made and further research is recommended to come to a fact based conclusion. The advantages and disadvantages of both single and dual stream recycling are general understanding.

“Dual Stream Recycling lessen contamination of materials” and “Single Stream Recycling increases public participation and recycling rates” these statements are yet to be verified by intensive research.