Putting Scrap Tyres Into Good Use
A Climate Change Mitigation Initiative
To Reduce Our Carbon Footprint
For A Greener World
More than 3 billion tyres will reach its end of life this year and should all of them be discarded would be a serious health and environmental issue. Tyres are designed and built to last and are not biodegradable, thus the problem caused by this accumulation is being compounded year after year.
If they are dumped in landfills, breeding grounds for disease carrying insects and pests would be created. Furthermore, fires can easily occur in these landfills, spewing noxious smoke into our atmosphere and causing run-off of toxic oil and heavy metals into our ground and water.
However, those same characteristics which make scrap tyres such a challenge in disposal also make them suitable to be reused for numerous applications because rubber is such a resilient material.
The management of scrap tyres can be categorize into:-
– Product recycling
– Material recycling
– Energy recovery
– Landfill
Product recycling
Scrap tyres, whether used as a whole, cut or granulated, can be used in many civil engineering applications to take advantage of their shape, impact and sound absorption properties or material characteristics.
Coastal and Ground Protection
Some applications:-
- erosion barriers
- slope protection
- sea walls
- dock fenders
- artificial reefs
- off-shore breakwater
Material Recycling
i. Reclaim Rubber
Scrap tyres are shredded and granulated, and the rubber crumbs separated from the steel and nylon to be reprocessed into reclaim rubber for reuse.
Some applications:-
ii. Pyrolysis
Pyrolysis is the chemical conversion or breakdown of scrap tyres by heating in total or partial absence of oxygen.
Some applications:-
- oil that may be used as fuel
- scrap steel to be recycled
- char could be used as asphalt or cement filler
- gas for burning
Energy recovery
Scrap tyres represent an alternative supplementary non-fossil fuel. Tyre-derived fuel provides the same heat energy achieved by coal.
Some applications:-
- cement and lime kilns
- steel mills
- power generation plants
- steam generation for industrial uses
- incinerators for burning refuse
Landfill
Landfill is the least desired options, and should be adopted only when no viable alternative exists.
Tyres can trap methane gases, causing them to become buoyant, rising to the surface. This effect can damage liners that have been installed to help keep landfill contaminants from polluting the environment and becoming a health hazard.
Risk of fire would also be a major concern.
Applications for Steel and Nylon Fibres
Scrap steel applications
- cut wire pellets
- wires
Scrap nylon applications
- ropes
- safety nets