Among the measures to reduce PM emissions, street cleaning (water only) and the application of calcium magnesium acetate (CMA) on roads was tested to prevent or reduce emissions of PM by resuspension of dust previously deposited on circulating ways, at both URBAN and INDUSTRIAL areas, with high traffic density.
Concerning INDUSTRIAL areas, AIRUSE has performed tests both on paved and unpaved industrial roads.
PAVED ROAD: The tested paved road in one of the most important ceramic tile clusters of Europe was selected: l’Alcora. This road shows a traffic density of heavy vehicles higher than 500 trucks a day, mainly carrying powdered raw materials. Therefore, significant amounts of dust are deposited on this roadway.
The study was carried out from 26th June 2014 until 31st July 2014 with the cooperation of l’Ajuntament de l’Alcora (the City Council and the local police), as well as with the companies located at the selected road. After a first control period without cleaning, 5 applications of about 50 g /m2 of CMA were implemented throughout the study period.
To evaluate the effectiveness of steet cleaning and the application of the CMA on reducing PM emissions, PM and gaseous pollutant concentrations were continuously measured and recorded, using a mobile lab located in the studied road, equipped also with a PM high volume sampler to allow the chemical analysis of the collected PM10 .
UNPAVED ROAD: This video (July 2014) shows the comparison between two mitigation measures for the prevention of emissions of PM on not asphalted roads: the application of water (left) and the application of water complemented with spraying of 200 g/m2 of CMA (right). Under the image of each experience, a chart is showed with the temporal evolution of the concentrations, recorded continuously in the vicinity of the road. This chart also identifies the elapsed time, which is accelerated in the video.
In the selected road there are exclusive and continually dump trucks that carry blasting material from a quarry nearby. Unlike what happens with road dust emissions in urban environments, the emissions generated on non-paved roads are perfectly visible. It can thus be noted, both visually and by the time series of concentrations, that water irrigation is an effective measure which almost completely eliminates the emission. However, the effect does not persist indefinitely, so irrigation must be periodic throughout the day, as does the company that owns the selected path. The application of CMA did not appear to contribute or to reduce emissions or to prolong the effect of irrigation, at least in a meaningful way.