Bitumen expanding using bio-oil product of rose pulp’s pyrolysis process

•Waste rose pulp has been reused after pyrolysis process.•Mixing and compaction temperature are reduced up to 8 °C.•Neat bitumen ratio is decreased up to 2.4%.•Strength value is increased up to 4.1%. Within the study, the usability of rose pulp, which is the common waste of many industrial products produced by using rose, was examined as bitumen modification material. In order to investigate this possibility and potential benefits, waste rose pulp was subjected to the pyrolysis process to obtain the biochar, bio-oil and biogas. Since it has a viscous liquid form, the bio-oil product has been selected to modify the bitumen for this study. Supplied wet rose pulp was first dried until the water content decreases to around 10%. Afterwards, the dried rose pulp subjected to pyrolysis process for one hour at 450 °C after 30 min heating period. Used neat bitumen’s grade was PG 64–22. Bio-oil product has been mixed 2 and 4% by weight into the bitumen at 160 °C for 30 min. After the modification process, bitumen performance tests have been done. Because of the analysis, it was concluded that modification did not change the bitumen grade, reduced the mixing and compaction temperature up to 8⁰C and so saving energy. In addition, the modification increases the optimum bitumen ratio up to 5%, strength value up to 4.1%, tensile strength ratio (TSR) value up to 2.3%, and the wheel tracking depth up to 95.2% but still remains within the Hamburg wheel tracking test specification limits.