Energy Consumption and Greenhouse Gas Emissions of High Rap Central Plant Hot Recycling Technology Using Life Cycle Assessment:case Study

Traditional LCA of central plant hot recycling shows that, the higher RAP added, the less energy consumed. This conclusion is mainly based on the calculation of reduced raw material. However, when the content of Reclaimed asphalt pavement mixture (RAP) reaches some level, it is needed to take measures such as using additive or improved construction method for maintain the performance of asphalt pavement. For the situation of high RAP central plant hot recycling technology has become more and more widely used, in order to evaluate its effect of energy saving and emission reduction, this paper investigate and compare the life cycle energy consumption and greenhouse gas emissions with the method of LCA, with considering the matters of RAP addition, asphalt-recycling agent, warm agent and transport distance. The study results indicate that, it is not appropriate say that the higher RAP added, the less energy used. Raw material transportation distance is the key factor of energy consumption and greenhouse gas emissions, while asphalt-recycling agent is the least factor. Besides, with theoretical calculation of different warm mix method, the result show that mechanical foaming is more energy saving than the organic additive warm agent, while being used in high RAP central plant hot recycling.