Estimation of cumulative energy demand and green house gas emissions of ethanol foamed WMA using life cycle assessment analysis

Abstract

The purpose of this project is to evaluate the possibility of using ethanol as a foaming agent for low emission asphalt technology via life cycle assessment (LCA) analysis. LCA analysis was conducted at two different stages. Firstly, the analysis was performed to estimate the energy consumption and CO2 emission in the cradle to gate stages incorporating the effects of various foaming agent contents. In the second assessment, the analysis attempts to incorporate the required information based on the available published papers to get a clear idea about the energy consumption and GHG emission involved in all stages from the raw materials production to the end of life of asphalt pavement. The scope and boundaries of this analysis have been set based on several assumptions made prior to performing the analysis. LCA software, SimaPro 7.3, was used to estimate the cumulative energy demand and global warming potential (GWP) of Ethanol-foamed Warm Mix Asphalt (EWMA) and compare these to the results of Hot Mix Asphalt (HMA) and Water-foamed Warm Mix Asphalt (WWMA). Eco-Indicator 95 analysis was also conducted to establish the weighting factors for the various environmental effects of each asphalt mixture. Based on the results, it was found that the EWMA performed better in terms of energy demand, and lowered GHG emissions compared to HMA and WWMA. EWMA has high potential to reduce the detrimental impacts from the asphalt pavement industry based on Eco-Indicator 95 analysis, which has a lower impact in terms of GHG emissions, ozone layer depletion, acidification, eutrophication, summer smog, and winter smog, as well as energy resources.