On the road to more sustainable asphalt
AN industry group, funded by investment from the Carbon Trust under the Industrial Energy Efficiency Accelerator (IEEA), has embarked on a two-year research initiative to develop a unique approach for more sustainable asphalt production. Led by Tarmac Ltd, the project team consists of Nynas UK, Atkins and the Mineral Industry Research Organisation (MIRO).
The group aims to design, test and demonstrate the viability of semi-warm and cold-temperature asphalt as an alternative to the traditional hot-mix material. The ultimate goal is to save energy in the asphalt production process and reduce the carbon footprint of roads, by developing more carbon-efficient technology and new specifications that can be adopted across the UK.
‘This project is an important step in making the UK asphalt and road industry more sustainable and carbon efficient. By reducing the temperatures needed during asphalt production we can minimize energy consumption and achieve major reductions in asphalt-related carbon emissions,’ explained Dr Nizar Ghazireh, project director at Tarmac Ltd.
‘In addition to the technical research we’re carrying out, this project will also deliver workable specifications that allow lower-temperature asphalts to be adopted by UK highway operators.
‘Early indications are that this approach can also offer significant carbon savings in transportation (the major carbon contributor in the aggregates sector) through the use of mobile plants and manufacturing cold-mix using locally sourced recycled asphalt planings.’
Nynas UK’s product application manager for cold-paving technology, Dennis Day, added: ‘Low-temperature asphalts have been used extensively overseas but the technology has not been employed as much in the UK. A major obstacle has been a lack of client understanding about the products and how they should be specified.
‘The support from the Carbon Trust will allow the project team to engage clients in developing guidelines which will help them specify lower-temperature asphalts – assisting the industry in reducing its carbon footprint.’
The benefits of using asphalt produced at lower temperatures have already been widely recognized across Europe. As part of the project, the group will undertake extensive production and demonstration trials to demonstrate the capabilities of semi-warm and cold-mix asphalt, including plant production, installation and in-situ product performance.
The project team will research and identify how these materials have been used and specified across Europe, and, through dialogue with key industry stakeholders, develop a guidance note to facilitate their use across the industry.
Tarmac and Nynas will work jointly using binder technology developed by Nynas in Europe and asphalt developed by Tarmac in the UK to lay the site trials. These sites will then be monitored and evaluated by Atkins and Tarmac, and the findings will be used to develop working specifications.