Bitumen rubber has been generically specified by the government, road authorities and owners for use in the construction of roads throughout the country.
The use of large amounts of recycled rubber crumb for the manufacture of road surfaces and related products is propelling South Africa towards a circular economy, where waste products are usefully used to address key infrastructure needs.
From tyre to road
The Mathe Group factory recycles approximately 1 000 radial truck tyres per day, to produce 45 tons of rubber crumb. Much of this production goes to bitumen product manufacturer, Tosas, to be used in the manufacture of rubber modified bitumen.
This product is being used by the South Africa National Road Agency (SANRAL) for massive upgrades to the N1 in Gauteng and the N2/N3 leading from the port of Durban.
Rubber bitumen being applied for a spray-seal application.
Building with bitumen
Deon Pagel, managing director of Tosas, explains that although people still refer to so-called black top roads as “tarred” roads, the use of tar, which is extracted from coal and is carcinogenic, has been discontinued. It has been replaced with bitumen, which is extracted from crude oil.
Bitumen, for chipseal applications, is sprayed onto the road surface at up to double the temperature of boiling water. This seals the top road layer, protecting the foundation layers beneath and acting as a waterproofing layer. Alternatively, it can be mixed in with the asphalt and acts as a glue, strengthening the road itself.
The road ahead
Mathe Group’s role goes beyond simply producing rubber crumb through the ambient grinding of radial truck tyres for Tosas. Together with Tosas, it designed and developed a second plant to produce what is known as New Crumb Rubber Technology (NCRT). This involves coating the rubber crumb with aromatic oil and specialised waxes to produce a pre-swollen rubber crumb, which is bitumen rubber for asphalt mixes and spray-seal applications, that have greater longevity and much lower mixing temperatures.
With plans to double the output at its Hammarsdale factory, Dr Mehran Zarrebini, chief executive officer (CEO) of Mathe Group, is confident that the company can accommodate the growing need for rubber crumb for roads as well as other applications.
Room for growth
According to Dr Zarrebini, there is room for growing the amount of rubber crumb utilised in the roads industry, although this is largely dependent on SANRAL awarding tenders for infrastructure projects and having the available funding to follow through with these projects.
Issue: Moving closer to a circular economy.
Solution: Mathe Group and Tosas are working together to convert old tyres into rubber crumb bitumen, one of the most superior road bitumen products in the world.
For more information, contact Mathe Group:
Tel: +27 87 460 0400
Email: sales@mathegroup.com
Website: www.mathegroup.com
LinkedIn: https://www.linkedin.com/company/mathe-group/
X: @mathegroup