By 2005, there were over 480,000 tonnes of used tyres arisings per year in the UK (Environment Waste Strategy, 2007). Since July 2006, both whole and shredded tyres have been banned from landfill, following implementation of the UK Landfill Regulations. There is therefore an urgent need to find new applications and markets for tyre arisings.
In November 2005, BRE was commissioned by WRAP to identify applications for waste tyres in construction products. The principal objective of the project was to use tyre waste to develop and provide industry with a number of new sustainable, viable, low-cost composite construction products that are easy to manufacture. The aim of the project was to contribute to the remit of WRAP to reduce the volume of waste tyres going to landfill, and to research new market opportunities for waste tyre-derived materials. The project was completed in March 2007.
The objectives of the project were:
- to understand and characterise waste-tyre raw materials;
- to establish the properties, reactivity and functionality of these raw materials for the development of construction composites;
- to develop a ‘matrix-used tyre-performance-demand’ model for used tyre-based composites;
- to investigate the modification of a new generation of reprocessed used tyre constituents, if necessary;
- to develop new processes for manufacturing these composites.
The main tasks undertaken under the project were as follows:
- property testing of the tyre-derived raw materials, including recommendations on raw material including recommendations on raw material modifustry consultative group;
- laboratory manufacture of prototype products identified by BRE and an industry consultative group;
- assessment of the properties of the developed prototypes;
- development of a matrix of used tyre vs. property demand for the plasterboad/tyre buffings-derived panel;
- industrial assessment of the plasterboard/buffings product;
- assessment of economic and market factors;
During the project, a series of prototypes based on a range of waste tyre-derived raw materials (shreds, dusbuffings) with plasterboard, oriented strand board (OSB) and laminate floor were produced. A plasterboard sandwich panel with a rubber layer in the middle was successfully developed and a variety of this subsequently tested by Lafarge Gypsum, who were interested in its acoustic insulation properties. Further work is still needed to bring this product to market, but results so far are promising. The results of the tests are given in AppenA range of other potential products were prototyped in the laboratory, including underlay for use beneath laminate floors, and sandwich panel for door or wall partition with OSB. However (with industry agreement), these have not been taken further at this stage, some of them because they appear to be uneconomical given current cost models.
Members of an industry consultative group contributed to the project through the provision of testing facilities, materials and advice. Key contributors were: Murfitts Industries, Charles Lawrence International Ltd, CEnvironmental Ltd, Tyre Recovery Association, Biffa Was Composite construction products from waste tyres 1.