A Study of the Size Distributions and the Chemical Characterization of Airborne Particles in the Vicinity of a Large Integrated Steelworks

An atmospheric measurement campaign took place in the spring of 2006 to characterize the emission of particles from an integrated iron and steelmaking site. During the measurement campaign, the PM10 daily limit value of 50 µg/m³ was not exceeded on any day; however, excursions in PM10 concentrations occurred over periods of a few hours associated with wind passing over the steelworks’ site. Measurements with an Aerosol Time-of-Flight Mass Spectrometer (A-TOFMS) identified six particle classes linked to emissions from steelmaking processes, including iron-rich particles with internal mixing with nitrate and phosphate. Subsequent analysis identified these as arising from the ironmaking sector and the hot and cold mills as the dominant sources. Other A-TOFMS classes were found to be rich in lead, zinc, and nickel, also attributed to steelmaking sources. A Micro Orifice Uniform Deposit Impactor (MOUDI) was employed to measure particle size distributions over periods of 19–42 hours, revealing two characteristic size distributions for iron: one bimodal with modes at 0.45 µm and 4 µm, and the other unimodal centered at 6 µm, with the smaller mode exhibiting a peak for lead at the same particle size.