Preparation for Industrial Scale Implementation of Eco-Friendly Foamed Bitumen Mineral-Asphalt Mixtures

How to Produce Eco-Friendly Asphalt?

What is commonly referred to as asphalt is, in reality, a mineral-asphalt mixture used to construct road pavements. Asphalt itself serves as the binder that holds aggregate grains together, which account for over 90% of the total content in such mixtures. Combining asphalt binder with aggregates requires heating these materials to relatively high temperatures, posing one of the primary challenges associated with mineral-asphalt mixture production. First, this process generates high emissions of hazardous compounds into the atmosphere; second, heating causes the asphalt binder to alter its properties through aging processes right from the manufacturing stage. Another growing issue is the depletion of natural aggregate deposits driven by intensifying construction activities. Agnieszka Woszuk, Ph.D. Eng., from Lublin University of Technology, is addressing these challenges by developing a novel, eco-friendly production method for mineral-asphalt mixtures. Her research is funded by the European Funds for a Modern Economy 2021–2027 (FENG) program under the Proof of Concept action implemented by the Foundation for Polish Science (FNP).

Pavement cracking and crumbling, typically observed during spring, are largely the result of binder aging. Over time, asphalt changes its properties, becoming increasingly stiff and brittle. Temperature fluctuations accelerate this aging process, which initiates during the production of the mineral-asphalt mixture itself. Higher manufacturing temperatures result in more rapid and severe binder aging. Consequently, the asphalt binder turns brittle, stiff, and prone to low-temperature cracking, leading to significant road degradation in spring. Damaged asphalt pavements are milled, and after appropriate processing (such as crushing), reclaimed asphalt pavement (RAP) is produced. RAP can be added to new mixtures to partially replace virgin aggregates. However, because RAP contains aged, stiffened asphalt, its addition is typically capped at around 10% to preserve the structural quality of the final mixture.

"The project I am leading aims to develop a manufacturing method for mineral-asphalt mixtures that addresses all of these challenges—reducing production temperatures while simultaneously improving mixture quality and durability. This approach will extend the pavement service life and allow degraded pavements to be recycled into RAP for reuse in new mineral-asphalt mixtures. By utilizing suitable softening agents for the aged asphalt, its original properties will be restored, allowing for higher percentages of RAP in new mixtures. This new technology is more environmentally friendly in several ways: it reduces atmospheric emissions and lowers the demand for virgin aggregates mined from natural sources," says Dr. Agnieszka Woszuk.

The planned experimental campaign encompasses both laboratory testing and industrial-scale technology trials. During the laboratory phase, binder test results will be used to optimize the process conditions for blending asphalt with aging inhibitors. Subsequently, the quality parameters of the final product—the mineral-asphalt mixture incorporating RAP—will be thoroughly evaluated. The final stage of the project involves testing the eco-friendly production technology under real-world, industrial conditions in collaboration with an industry partner. "This is a crucial phase, as transitioning from micro-scale to macro-scale is challenging. In the laboratory, we produce several kilograms of mixture under strictly controlled conditions, whereas actual industrial production reaches dozens of tons per hour, which may introduce new operational challenges. However, if any arise, we will address them," concludes Dr. Agnieszka Woszuk.

Agnieszka Woszuk, Ph.D. Eng., is a graduate of both the Faculty of Civil and Environmental Engineering and the Faculty of Management and Fundamentals of Technology at Lublin University of Technology. She has authored and co-authored 21 publications indexed in the Journal Citation Reports (JCR). Dr. Woszuk has participated in 11 research projects, serving as principal investigator on five of them. She possesses extensive experience in technology transfer and commercialization, holding 25 patents, 15 industrial implementations, and 21 technical reports and expert evaluations for industry. Her professional background includes two scientific research fellowships at foreign academic institutions and two industrial internships at road construction companies. For her inventions and technological implementations, she has received numerous awards, including a Gold Medal at the International Exhibition of Inventions and Technology INNO WINGS (2022), the Platinum Award at the 15th International Invention and Innovation Show INTARG (2022), the Minister of Education and Science Award for Implementation Achievements (2022), Intelligent Development Forum Awards ("Meritorious for Intelligent Development" in 2020 and "Young Innovative Science Leader" in 2018), as well as the Honorary Badge "Meritorious for Invention" awarded by the Prime Minister of Poland (2021).