Over the past two years bituminous road binders incorporating a proportion of biogenic (plant grown) material were introduced in Australia. These binders have significantly reduced carbon footprints, because plants absorb atmospheric carbon dioxide and store the carbon. The carbon bearing plant material is processed into a biogenic bitumen component and blended with conventional bitumen. When the resulting binder is used in roads this completes the permanent sequestration of the carbon from the atmosphere.
This first generation of biogenic binders meets existing binder specifications and is now widely used and accepted in Australia. The journey towards binders with a net zero carbon footprint continues. This paper presents the development of the next iteration of biogenic binder. It is technically possible to create road binders with a net zero carbon footprint, but changes to petroleum orientated bitumen specifications will be required for these products to enter the market.
