Laboratory identification of fumes during manufacturing of hydrocarbon mixtures

Increasingly there are more demanding health and environmental criteria involved in the construction field and thus in the road construction and maintenance domain. This requires a better understanding of the fumes generated during the manufacturing of hydrocarbon based materials. This study carried out at the Laboratoire Central des Ponts et Chaussées (LCPC) is part of a research partnership between Shell Bitumen and LCPC in order to determine the nature of the organic compounds emitted during mixing of hydrocarbon maerials used as road construction products, such as the fundamental parameters influencing emissions (mixture features an process used). These organic components include Polycyclic Aromatic Hydrocarbons (PAHs) and Total Organic Compounds (TOC). In this study LCPC has developed a device allowing the collection of fumes from bituminous mixtures. The analysis of emitted TOC was continuously carried out during mixing, using a FID type TOC analyser. The analysis of PAHs trapped on filters was performed in the Shell Bitumen laboratory using high pressure liquid chromatography HPLC equipped with a fluorescence detector. Firstly, feasibility measurements were performed to establish a reliable test protocol and to determine the test repeatability. Then, the evolution of the organic emissions with time was studied. The results obtained highlight the influence of mixing conditions on the nature and the quantity of the emitted compounds.