Best Practices Report: Compaction vs. Loose Collection

Both compaction and loose collection methods of curbside recycling have advantages and disadvantages. While compaction-equipped vehicles will yield greater amounts of material on a collection route, the compaction process greatly increases the possible introduction of contaminants to the PET recycling process. NAPCOR reports the following "best practices" to maximize the efficiency of PET curbside collection. These best practices were developed by the Association for Post-Consumer Recyclers, the Clean Washington Center for the Environmental Protection Agency, and NAPCOR.

The Benefits of Compaction

Collecting recyclables in compaction vehicles, like the ones used to collect household trash, offers many benefits in the collection and transportation of recyclables. Longer routes, faster collection, and more efficient loads for transportation are among the clear advantages of compaction. However, if compaction is used to increase the efficiency of a curbside program, communities should examine and, if necessary, alter the mix of recyclable materials collected through the curbside program to avoid some of the serious contamination problems that can be encountered.

Glass Contamination

When commingled containers get compacted, there is a much greater tendency for glass breakage than when collection occurs without compaction. When glass breaks, small pieces of glass can get trapped inside PET bottles and containers. This trapped glass can cause serious damage to processing equipment throughout the PET recycling process. Therefore, the best practice for curbside collection of PET plastics in compaction vehicles is to collect PET plastic containers commingled with other recyclable containers except glass.

Curbside collection programs that have utilized compaction vehicles and excluded glass from the mix of recyclables report the best collection efficiencies and economics.

Alternatives to Glass Compaction

Glass can be collected efficiently in the same vehicles as PET plastic and other commingled recyclables if collection workers sort the materials at the curb and place all glass in a separate collection compartment. Also, communities may elect to collect recyclable glass through a separate companion program if materials are collected in an automated fashion during which no curbside sorting takes place.

Finally, many programs around the country have established convenient drop-off locations strictly for glass containers while removing glass from the list of acceptable curbside collection materials. These alternatives allow communities to maintain efficient curbside collection systems while still offering recycling opportunities for a variety of materials.