Single-stream (also known as “fully commingled” or "single-sort") recycling refers to a system in which all paper fibers, plastics, metals, and other containers are mixed in a collection truck, instead of being sorted by the depositor into separate commodities (newspaper, paperboard, corrugated fiberboard, plastic, glass, etc.) and handled separately throughout the collection process. In single-stream, both the collection and processing systems are designed to handle this fully commingled mixture of recyclables, with materials being separated for reuse at a materials recovery facility.[1][2]
The single-stream option replaces the dual-stream option, which is where people separate certain recyclable materials and place them in separate containers for collection. Typically, dual-stream has partial commingled materials such as glass, plastic and metals in one stream separated from paper products in the other stream.[3] From an end consumer perspective, single-stream is easier to participate in. However, single-stream recycling has disadvantages, including the output of lower quality plastics and paper to recyclers. This lower quality material has to be processed more downstream. The increased flow of decreased quality recyclables from Europe and North America in part due to single-stream recycling was part of China's motivation for launching its Operation National Sword policy.[4]