In response to these issues, dual-stream recycling emerged. By separating mixed paper into one bin, and all containers in another, this helped solve issues such as expanding the scope of recycling, while making things more simple for residents, and increasing the efficiency of curbside collection.
Due to the commingling of products, however, this approach led to the need for materials recovery facilities (MRF) to sort various materials, utilizing both manual and mechanical processes.
In the latter 1990s, single-stream recycling emerged. Single-stream or commingled recycling involves the placement of all allowable materials in the same curbside container, as well as mixed together on the same collection truck. This approach facilitates ease of recycling for both residents, thereby increasing recycling rates, as well simplifying curbside pickup, facilitating the introduction of automation, and requiring fewer collection trucks.
Single-stream recycling has its own set of challenges, however, with respect to contamination of materials, loss of potentially recyclable materials, and the non-recyclable residuals requiring disposal after sortation. Single-stream recycling also requires labor intensive, or equipment intensive sorting processesCompare curbside recycling container prices.