Waste tyre pyrolysis involves the thermal degradation in the absence of oxygen to produce a gas (or liquid) that can be for fuel. The pyrolysis method for recycling used tyres is a technique which heats whole or shredded tyres in a reactor vessel containing an oxygen free atmosphere and a heat source. In the reactor the rubber
is softened after which the rubber polymers continuously breakdown into smaller molecules. These smaller molecules eventually vaporise and exit from the reactor. These vapours can be burned directly to produce power or condensed into an oily type liquid, generally used as a fuel. Some molecules are too small to condense. They remain as a gas which can be burned as fuel. The minerals that were part of the tyre, about 40% by weight, are removed as a solid. When performed well a tyre pyrolysis process is a very clean operation and has nearly no emissions or waste.
One of the great advantages of pyrolysis is that it is environmentally friendly, not only in it’s process, but in the fact that it provides a opportunity of eradicating the huge stockpiles of used vehicle tyres that blight our environment.
ETL (Pty.) Ltd. Botswana has been involved in negotiations with the Botswana Chamber of Mines and Debswana Diamond Mine in Jwaneng to install a 100 ton per day Waste Tyre Pyrolysis Plant in order to recycle thousands of tons of waste tyres that has been stockpiled over the years and is posing environmental and storage problems due to the tyres not being easy to dispose of.
The plant will be situated approximately 7km from the mine and will create over 300 jobs in the districts of Jwaneng and Sese. The total investment is in the region of BWP150 Million and will take 12 months to install and commission. The products that will be produced from this plant are:-
The plant will produce 16 million litres of Diesel, 9000 tons of Carbon Black and 4500 tons of Steel per annum.
Advantages of Tyre Recycling: