Application of biochar from crop straw in asphalt modification

Abstract

The objective of this study is to verify the feasibility of using biochar made from crop straw as a bitumen additive to improve some properties of bitumen. The differences between crop straw biochar prepared in a laboratory and commercial charcoal were investigated through scanning electron microscopy and laser particle size analyses. Furthermore, biochar-modified asphalt was prepared using the high-speed shear method, and the penetration, softening point, ductility at 15°C, and apparent viscosity of the asphalt binder with 6% biochar were measured at 120, 135, 150, 160, and 175°C. It was found that both the crop straw biochar and the commercial charcoal consist mainly of C, O, Si, and K, but the C content of crop straw biochar is slightly higher than that of commercial charcoal. The particle size of biochar is smaller than that of commercial charcoal, while the specific surface area is larger. It was determined that the addition of crop straw biochar significantly improved the high-temperature performance of asphalt, and that biochar and commercial charcoal have a similar influence on the high temperature performance of asphalt.

The efficiency of bio-char as bitumen modifier

“…Like other powders containing micro- and nano-sized particles, which have been shown to have a beneficial effects on bitumens even at low percentages [ 23 ], bio-char allows for increased pavement loading capacity and decreased fatigue cracking during the pavement's operational life. pavement, as widely reported in the literature [ [24] , [25] , [26] ]. Anti-aging effects have also been explored.…”

Biochar for agronomy, animal farming, anaerobic digestion, composting, water treatment, soil remediation, construction, energy storage, and carbon sequestration: a review

“…The addition of straw-derived biochar significantly improved the high-temperature performance of asphalt. Biochar performed comparably to commercial coal in this investigation, and it was determined that 6% of straw-derived biochar powder should be used in asphalt applications (Gan and Zhang 2021 ).…”

Performance Study on Laterite Road Base Stabilised with Emulsions Incorporating Biochar

“…When used as a construction material, biochar essentially acts as a carbon sink, potentially sequestering carbon for hundreds of years within the built structure. In the realm of road construction, biochar is primarily utilised in flexible asphalt pavements to produce bioasphalt and modify asphalt binders, thereby reducing carbon emissions [9][10][11][12][13]. The inherent properties of biochar, including high stability, large surface area, and aromatic structure, contribute significantly to enhancing the mechanical properties of asphalt bitumen [6].…”