Mattress recycling

Mattresses, which are classed as bulky items, can enter the waste stream either by kerbside collection or by way of household waste recycling centres. They are of a composite construction, with a material panel over a steel spring assembly. The design is heavily influenced by type and manufacturer. An analysis of a range of mattresses entering a recycling facility was undertaken and key physical parameters were determined to assess type, size, mass and methods of construction. Of the mattresses entering the facility, 58% were classed as double size and the remaining 42% were single. It was found that the panels were attached to the spring assembly by staples and they were either unstitched, stitched together using a range of designs or joined using tufted buttons. Furthermore, 98% of the mattresses examined were of a simple open spring design. The average mass varied from 15 kg for single mattresses to 25 kg for doubles. The steel spring assembly accounted for about 45% of the total mass. Currently, recycling takes place in dedicated centres using manual or automated processes. The type of construction heavily influences the recycling route: stitched panels are sent to energy from waste plants, whereas unstitched material is sent for further processing due to its ease of separation. The calorific value of the panel material ranged from 18·55 to 23·78 MJ/kg, making them ideally suited to energy applications.