Quantification And Factors Influencing Fugitive Dust Generated During Road Sweeping

Road dust is a principal form of dust in urban areas, and the road dust caused from street cleaning is an important component of it, which is also the major source contributing to the dust. In the present day, there are two main ways to clean the streets in urban cities:mechanical cleaning and manual cleaning. While street cleaning is an efficient way to keep the road clean, it is the road dust maker as well. The dust caused form street cleaning contributes a large proportion of dust pollution in urban cities, and the dust pollution is a major type of particulate air pollution, which jeopardizes the environment and human health. Chongqing is situated at Sichuan Basin, covering a large area crisscrossed by mountain, which means that there is a large source of dust pollution. Besides, as an important industrial city, the particulate air pollution in Chongqing is severe. Therefore, due to the geographic condition that can easily give rise to haze weather and the particulate air pollution, the control of dust pollution can’t be ignored. Since relevant research on the control and quantificational calculation of dust pollution causing by street cleaning is rare, this experiment conducts a method of stimulation test by stimulating mechanical cleaning and manual cleaning in order to investigate the street cleaning’s influence onthe quantity of road dust and the rule behind in Chongqing. We have constructed a quantitative calculation model of the TSP density dust by mechanical cleaning and manual cleaning. And we think this model is be instructive and meaningful for enacting measures on the control of road dust causing by street cleaning and improving the efficiency of environmental work. This study demonstrates that:During the process of mechanical street cleaning, the material of road, road dust load, the mechanical machine speed, and Sampling height will affect of the quantity of dust, which occupy36.15%、32.63%、20.73%and10.49%of the dust causing by street cleaning respectively. The weather condition and number of cars play a less important role during the mechanical cleaning. In manual cleaning, the humidity of dust, road dust load, Sampling height and cleaning strength will influence the quantity of dust, and they make up75.64%.9.71%、8.69%and5.96%of the road dust respectively.In mechanical cleaning, the quantity of dust from cement road is larger than from tarmac road, and the mechanical machine speed, Sampling height, and road dust load will also bring about the road dust, which means that faster speed, higher dust load, and The higher the sampling height contribute to more dust within certain limits. While in manual cleaning, the cleaning strength, road dust load, and Sampling height will increase the dust, which means that bigger cleaning strength, higher dust load, and the higher the sampling height contribute to more road dust within certain limits. The humidity of road dust, in fact, has inhibiting effect on road dust. Therefore, higher humidity means less road dust.In mechanical cleaning, the model of the effect on road dust(y) from the road material(x1),cleaning speed(x2),road dust load(x3) and Sampling height(x4) is:y=0.1446-0.1473x1+0.0146x2+2.00821x3+0.0857x4.In manual cleaning, the model of the effect on road dust(y) from cleaning strength (x1),road dust Ioad(x2),humidity of road dust(x3) and Sampling height(x4) is:y=0.5875+0.0016x1+0.2236x2-0.0099x3+0.0435x4.We have constructed a mathematical model of multivariate curve regression of road dust in mechanical cleaning(y),cleaning speed(x1), road dust load(x2), and traffic flow(x3):yi=p1x1+p2x2+p3x3+p4sqrt(x1)+p5sqrt(x2)+p6sqrt(x3)+p7.In manual cleaning, the mathematical model of multivariate curve regression of road dust (yi), road dust load (x1),humidity of dust (x2) and cleaning strength (x3): y1.0m=0.2364x1-0.0125x2-0.0043x3+0.0222sqrt(x1)+0.0169sqrt(x2)+0.0421sqrt(x3)+0.229y1.4m=0.3617x1-0.0127x2-0.0061x3-0.0949sqrt(x1)+0.0172sqrt(x2)+0.0523sqrt(x3)+0.245y1.6m=0.3829x1-0.0131x2+0.0007x3-0.1095sqrt(x1)+0.0136sqrt(x2)+0.0047sqrt(x3)+0.242Manual and mechanical cleaning have their own advantages in that mechanical cleaning is efficient and safe, while manual cleaning is more adapted to the working environment and does not requires high-quality labors, which is a kind of simple and physical work. Rational use of the two ways will improve working efficiency as well as environment benefits.