Bitumen obtained from petroleum has traditionally been used to make asphalt as a raw material and binder. TNO has developed a sustainable alternative for this: ECO-Bind. Biomass as a residual product from the waste water treatment can be used as an environmentally friendly substitute for bitumen. This offers the asphalt industry and road construction a great opportunity to become more sustainable.


Bitumen scarcer and more expensive

The idea arose from the research project 'Advanced Solutions for Asphalt Pavements' by TNO in collaboration with TU Delft. The aim was to use biopolymers and bio-oils from waste water streams in asphalt mixtures. Because now that oil is becoming scarcer and more expensive, the asphalt industry is finding it increasingly difficult to get bitumen supplied at reasonable prices. Research has been done into alternatives such as vegetable oils, such as soybean, palm or sunflower oil, but the drawbacks are the unnecessary claim on valuable land and competition with food supplies.

Lab proven

ECO-Bind has proven itself in the laboratory as a suitable replacement for bitumen. A practical test will follow in the near future under real weather and traffic conditions. This could mean a radical turnaround for road construction. The global road network is estimated to cover 65 million kilometers. About 750 billion euros is spent annually in the EU, US and China on roads construction and maintenance. The complete replacement of bitumen with an environmentally friendly product in the long term reduces dependence on fossil raw materials and at the same time means that much less polluted water is discharged into rivers, lakes and seas.

Microorganisms in wastewater

The biopolymers and bio-oils required for ECO-Bind are formed by micro-organisms in the wastewater treatment process. For example, sludge can be digested, resulting in polymer-containing bacteria. The biopolymer (PHBV) separated from this serves as a replacement for bitumen, while the remaining residue contains nutrients for soil fertilization.

First major innovation in a century

The application of ECO-Bind would mean the first real innovation with a major environmental impact in road construction after a long time. Over the past century, the composition and production of asphalt have hardly changed, except for the ban on tar. Experiments have been done with biomaterials in the last two decades, but these have not yet led to a real breakthrough.

Complete replacement of fossil bitumen

With this new technology and application, the fossil-based bitumen can be completely replaced in the long term. Dependence on crude oil is falling sharply, asphalt producers and road builders are innovating and society can continue to count on a good quality road network.

TNO is happy to enter into discussions with market parties that are interested in applying ECO-Bind or investing in its development.