Title: Method and mechanism research on highway asphalt pavement hot in-place and central plant recycling based on microwave and hot air combining multi-dimensional low temperature heating

Abstract

The recycling of waste asphalt pavement materials is a major problem faced by countries all over the world. Our country produces as much as 300 million tons every year, and long-term stacking takes up a lot of land and pollutes the environment. In 2021, the State Council clearly pointed out to promote the resource utilization of waste roads, asphalt and other materials. Hot recycling is one of the important ways. Traditional Hot recycling methods uses high temperature heating to cause asphalt aging and carbonization on the surface of the aggregate, which affects the fusion of new and old materials and asphalt, and is not conducive to recycling. Moreover, traditional hot in-place recycling has limited grading adjustment, large environmental pollution, and low quality of the recycled asphalt pavement; although the central plant recycling can adjust the grading greatly, it is limited by traditional heating. High-quality recycling is still not high, increasing transportation costs. The microwave regeneration heating efficiency is high and will not cause the asphalt to age. The regenerated asphalt mixture has better high temperature stability, crack resistance and fatigue resistance, but its heating cost is higher. Therefore, the research group proposed the method and mechanism research on highway asphalt pavement hot in-place and central plant recycling based on microwave and hot air combining multi-dimensional low temperature heating, from the heating method, mechanism and thermal regeneration method to jointly solve the current problems of thermal regeneration, in line with the national concept of developing a green and low-carbon circular economy, it has a clear leading and pioneering, innovative asphalt pavement recycling technology.