Monitoring and Quantifying Particles Emissions around Industrial Sites and Cities with Scanning Doppler LIDARs

Mining, quarrying and cement manufacturing plants, as with other heavy industrial activities involve a series of operations which can produce significant quantities of fugitive particles like dust or soot, with potentially adverse effects on the local and neighbouring environments. Effective control of their occurrence is necessary in order to comply with environmental regulations involving the maximum level of particle emissions, and also in order to optimize the operational processes of these industries. At some locations, industrial emissions can also be limited by the background level of particles as in desert areas, where dust concentration can be close to the maximum level of particles permitted. In addition to conventional in-situ particles counters located at specific points, the monitoring in 2D of particles around industrial plants or cities allows for better characterization and thus management of particles emissions. Scanning Doppler LIDARs have been used over the last decade for measuring wind for applications in wind energy, professional meteorology and aviaiton. They allow for accurate measurements of wind speeds up to a vertical height of 10 km based on the Doppler shift effect of aerosols. The signal reflectivity (CNR or Carrier-to-Noise Ratio) profiles can also be retrieved from the strength of the LIDAR signal. In this study, we will present the developments of new algorithms for detecting aerosol layers, and for retrieving aerosol optical properties like the relative and absolute attenuated backscatter coefficients. The use of these algorithms during two trials on two different industrial sites will be presented showing comparison of the retrieved mass concentrations of particles with conventional particles counters. The methodology developed as well as the current performances obtained will be detailed. The study will also show the ability of scanning LIDARs to provide both the quantification and the dynamics of industrial plumes over industrial plants. Figure 1 – Maps of relative backscatter coefficient over an industrial site in the North of France showing three plumes of particles. References [1] Otsu, N., 1979: A threshold selection method from gray-level histograms, IEEE Trans. Sys., Man., Cyber., vol. 9,‎ 1979, p. 62–66 [2] Bianco, L., Wilczak, J. M., White, A. B., 2008: Convective Boundary Layer Depth Estimation from Wind Profilers: Statistical Comparison between an Automated Algorithm and Expert Estimations, J. Tech. A, DOI: 10.1175/2008JTECHA981.1, 1397-1413. [3] Basart et al., 2012: Development and evaluation of the BSC-DREAM8b dust regional model over Northern Africa, the Mediterranean and the Middle East, Tellus B, 64, 18539, doi:10.3402/tellusb.v64i0.18539.