An eco-friendly asphalt pavement deicing method by microwave heating and its comprehensive environmental assessments

Abstract

The chemical deicing method and the conventional asphalt pavement deicing method by microwave have low efficiency, large construction pollution, and serious energy waste. This paper proposes an eco-friendly microwave deicing method based on the heat generation of the pavement's upper surface. In order to achieve the effect of heat generation on pavement's upper surface, four kinds of waste materials were selected to be mixed with asphalt mixture for experiments. Among these experiments, the temperature field distribution coefficient N was proposed to judge the appropriate types of admixtures, and the ice layer-pavement separation coefficient E was proposed to determine the admixtures' optimum content. Meanwhile, the effect of the heating equipment's moving speed on deicing and snow-melting was studied. Finally, a case study demonstrates this method has the effect of improving deicing efficiency, and comprehensive environmental assessments demonstrate this method has the effects of energy-saving and emission reduction. The results show that waste steel wool is the appropriate type of admixture for microwave deicing and snow-melting. The optimum waste steel wool content is 6%(by asphalt's volume). In addition, emissions are reduced by 5.34 kg in a unit of pavement (2 km long,7.5 m wide with 2 cm thickness of ice layer). The deicing speed can reach 9.7 km/h (36 kW). While improving the operating speed, the method protects the environment and also saves energy.