The Study On The Thermal Efficiency Of Old Asphalt Recycling Drying Cylinder And Its Structural Optimization

With the growing popularity and development of China’s highway, scrap asphalt regeneration becomes the focus of people’s concern, therefore used hot mix asphalt plant regeneration technology has become a hot research. Old asphalt drying cylinder is the key equipment of the old asphalt recycling system, it not only has impact on energy consumption and thermal efficiency, but also has a very important significance on energy saving.This article outlines the aging mechanism of asphalt pavement damage and regeneration of the old asphalt.It also has a brief introduction of the main structure forced intermittent hot mix asphalt plant reproducing apparatus and production process. Based on the research on the combustion characteristics of the fuel, the amount of fuel required for combustion air and flue gas volume produced, the combustion temperature of hot gas, fuel usage have benn calculed. It can calculate the thermal efficiency of the drying cylinder, and there is some room for improvement. The temperatre of hot air in drying cylinder can be calculated for each zone, thus each zone’s length can be devided. It analyses the temperature distribution in the drying cylinde and on the tube wall.It helps to verify the reasonableness of sectorization. Use Matlab to anlyse the influence of the mounting angle and the blade angle to the material temperatural rise,which helps to optimize the structure of the drying cylinder. Based on the simulation,we can find that when the two angles are 90 degrees, old asphalt can have the best material temperatural rise.Using box-shaped leaves in the preheating zone of the drying cylinder,which can improve its efficiency.