Characterization of effects of thermal property of aggregate on the carbon footprint of asphalt industries in China

- Specific heat capacity of aggregate has significant role on energy saving in asphalt mix production.
- Specific energy can be decreased from 30% to 64% owing to use of low specific heat capacity aggregate.
- Results clearly showed the energy saving is sufficient to supply power 44,007 to 664,880 Chinese households per annum.

In this study, the effects of the thermal properties of asphalt binders and aggregate materials were characterized in terms of the specific heat capacity (C) for energy consumption and environmental footprints of hot mix asphalt (HMA) and warm mix asphalt (WMA). Asphalt mixes produced using low-C aggregate are found to be more energy-efficient and environmental friendly, irrespective of the binder type and construction technology. Therefore, different fractions of aggregate blends were replaced with the aggregate provided from a low-C source or sustainable source. Analysis of energy consumption clearly indicated that the specific energy and environmental footprints decrease linearly as the low-C aggregate content increases. The amount of energy saving realized in the asphalt industries by the use of low-C aggregate is significant on a national scale in China. In this regard, China was chosen as a case study. Analysis of fuel requirement clearly indicated that the production of WMA using high thermal sensitivity aggregate can yield significant energy saving sufficient to fuel 44,007 to 664,880 Chinese households per year. Therefore, use of low C aggregate in asphalt mix production can be adopted as a strategy to produce WMA and HMA.