回收沥青方法研究——蒸馏温度和延迟时间

Study on Recycling Method for Asphalt——Distillation Temperature and Intercept Time

测试、对比了回收沥青和原沥青的基本性能、热失重和流变性能，分析了回收沥青和原沥青的微观结构．结果表明：采用阿布森标准方法（蒸馏温度165℃、延迟时间5min）回收的沥青针入度增加，软化点下降，15℃延度减小，135℃布什黏度上升，热失重增大，流变特性发生变化，并出现因氧化而生成的O-H，C-0，S-O和C-C基团，因此该回收沥青存在沥青老化和三氯乙烯残留问题；当蒸馏温度为135℃、延迟时间为1，2h时，回收沥青基本性能、热失重和流变性能与原沥青基本一致，没有氧化基团出现；当蒸馏温度为135℃、延迟时间为4，8h时，回收沥青中虽无三氯乙烯残留，但是其发生轻质油挥发和沥青氧化反应，因此建议在回收沥青时，蒸馏温度宜为135℃，延迟时间宜为1～2h．

The basic performance, thermal mass loss, rheological properties and microscopic of recycled as- phalt and original asphalt were tested and compared. The results show that when asphalt is recycled using standard method Abu Sen（distillation temperature 165 ℃, intercept time 5 min）, asphalt penetration in- creases, soft point decreases, 15 ℃ ductility shortens and 135 ℃ Brookfield viscosity rises, O-H, C-O, S -O and C ~C groups appear in infrared spectrogram, thermal mass loss rises and rheological properties change. So this recycled asphalt contains trichloroethylene and shows aging. If distillation temperature drops to 135℃, while intercept time is 1, 2 h,the basic performance of recycled asphalt is the same as the original asphalt, none groups generated by oxidation can be seen in infrared spectrogram, and thermal mass loss and rheological properties do not change. If distillation temperature drops to 135 ℃, while inter- cept time is 4,8 h,no trichloroethylene remain, but recycled asphalt shows aging. It is suggested that the distillation temperature should drop to 135 ℃ and intercept time keeps 1 -2 h.