Carbon dioxide (CO2) emission from bitumen during road constructionfor Greenhouse Gas emission calculations presentlyis taken based on its embodied emission factor.The direct emission component which accounts for significantemissions arising during heating of bitumen for mixing with aggregate is not accounted for.
This Paper presents findings of an experimental work of measuring direct carbon dioxide emitted by different bitumen binders during heating using Non Dispersive Infrared Radiation (NDIR) technology based CO2 analyzer.
Samples of various types of bitumen binders like Crumb Rubber Modified Bitumen (CRMB), Polymer Modified Bitumen(PMB), Viscosity Grade (VG)-30, and VG-40 taken from various sources were tested in the laboratory. Results from the experimental work show that there is direct, measureable emission of CO2 from bitumen binders during heating for mixing, and that this information should form the basis for more detailed investigation for assisting a better informed selection criterionbetween the straight run and polymer modified variants of bitumen binders.Comparison of emissions at their respective mixing temperatures, as specified in the Codes,shows that PMB-40 has the highest direct CO2 emission factor followed by CRMB-60, VG-30 and VG-40.