Ergon’s modified asphalt composition uses waste tyre pyrolysis oil
A recently granted patent (Publication Number: US11970619B2) discloses a modified asphalt composition that involves combining an asphaltic binder with a reduced-PAH pyrolysed oil fraction. The process includes pyrolysing rubber articles or rubber particles separately to obtain the pyrolysed oil fraction with a specified initial boiling point or flash point, and then removing polycyclic aromatic hydrocarbon (PAH) compounds from the fraction. Various methods such as fractionally distilling, solvent extracting, centrifuging, or wiped film evaporating are employed to eliminate PAH compounds from the pyrolysed oil fraction.
Furthermore, the patent claims specify the characteristics of the modified asphalt composition, including the maximum allowable PAH content, concentration of specific PAH compounds, carbon black solids content, transparency, flash point, and the percentage of the pyrolysed oil fraction in the overall composition. The composition can also include synthetic polymers to enhance its properties and can be used in asphalt emulsions for pavement construction or maintenance. Additionally, the patent describes a method for maintaining pavements by applying the modified asphalt composition as a pavement maintenance binder, followed by a layer of aggregate chips to create a skid-resistant surface. The temperature ranges for the pavement maintenance binder and asphalt emulsion are also detailed in the claims, along with the use of the modified asphalt composition in asphalt paving mixtures with aggregate.
This adds to the pathways to recycling tyre derived materials and to the sustainability of asphalt.
Source: Global Data
