A comprehensive review on asphalt fume suppression and energy saving technologies in asphalt pavement industry

Based on the environmental issues of high energy consumption and high emissions of asphalt fumes that are associated with hot mixing asphalt pavement construction, especially with modified asphalt mixtures such as waste rubber modified asphalt (WRMA) mixtures, significant environmentally-friendly new technologies have been successfully applied in the field of asphalt pavement materials. These include fume purification equipment, fume suppression or flame-retarding asphalt mixture, and warm mixing or cold mixing asphalt mixture. This paper provides a comprehensive review of the latest technology in this area regarding both asphalt fume suppression and energy conservation within the last six years. Firstly, asphalt fume suppression technologies in production, laying, and combustion scenarios of an asphalt mixture are identified, and asphalt fume purification equipment utilized in the production process is thoroughly examined. The impacts and mechanisms of various fume suppressants and flame retardants of asphalt fumes regarding their influence on the performance of asphalt pavement are discussed. Secondly, from the perspective of reducing asphalt mixture temperature, different mixing techniques such as cold mixing asphalt (CMA), warm mixing asphalt (WMA), and warm mixing based retarding viscosity asphalt (WM-RVA) are introduced and evaluated utilizing energy consumption and carbon emission evaluation models. These results show that the combination of advanced oxidation and traditional purification methods is critical for promoting the green production of asphalt mixtures. In-depth research on nanomaterials and composite-type asphalt fume suppression materials, WM-RVA, and effective combinations of high-performance modification, recycled materials, fume suppression functional materials, and WMA or CMA hold great promise for future development in this field.