Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Recycling Spent Asphaltic Concrete
Conventional asphaltic concrete paving materials comprise a major proportion of aggregate and an amount of asphalt cement sufficient to serve as a binder for the aggregate. The asphalt cement may consist of asphalt alone, or may include fillers or structuring materials such as sulfur, mineral dusts and fly ash, depending on the type of aggregate material employed. Various prior art processes have been employed for recycling of spent asphaltic paving mateials. According to the process of the invention, spent asphaltic concrete paving material may be effectively and economically recycled by means of a process comprising heating the spent material to a suitable mixing temperature, i.e., about 120 to 150C, in a nonoxidizing atmosphere, and mixing the heated material at that temperature with sulfur for a time sufficient to provide thorough mixing and reaction between the sulfur and the asphalt binder. This results in lowering the viscosity and increasing the penetration point of the binder with minimal lowering of the softening point. The process of the invention has been found to be particularly effective in recycling spent asphaltic paving material in which the aggregate consists of well graded aggregate materials such as graded crushed limestone or basalt, or combinations of the two, in which the particle sizes of the aggregate vary from about 3/4 inch to 200 mesh.
Recycling Spent Asphaltic Concrete
Conventional asphaltic concrete paving materials comprise a major proportion of aggregate and an amount of asphalt cement sufficient to serve as a binder for the aggregate. The asphalt cement may consist of asphalt alone, or may include fillers or structuring materials such as sulfur, mineral dusts and fly ash, depending on the type of aggregate material employed. Various prior art processes have been employed for recycling of spent asphaltic paving mateials. According to the process of the invention, spent asphaltic concrete paving material may be effectively and economically recycled by means of a process comprising heating the spent material to a suitable mixing temperature, i.e., about 120 to 150C, in a nonoxidizing atmosphere, and mixing the heated material at that temperature with sulfur for a time sufficient to provide thorough mixing and reaction between the sulfur and the asphalt binder. This results in lowering the viscosity and increasing the penetration point of the binder with minimal lowering of the softening point. The process of the invention has been found to be particularly effective in recycling spent asphaltic paving material in which the aggregate consists of well graded aggregate materials such as graded crushed limestone or basalt, or combinations of the two, in which the particle sizes of the aggregate vary from about 3/4 inch to 200 mesh.
Recycling Spent Asphaltic Concrete
W. C. McBee (Autor:in) / T. A. Sullivan (Autor:in)
1979
3 pages
Report
Keine Angabe
Englisch
Recycling Spent Asphaltic Concrete
| NTIS | 1979
Hot Plant Recycling of Asphaltic Concrete
| NTIS | 1980
| TIBKAT | 1962
| Engineering Index Backfile | 1922