AIR QUALITY MANAGEMENT at URBAN REGIONAL and GLOBAL SCALES 4 International and IUAPPA Regional Conference,10-13 September 2012 Istanbul-Turkey

AIR QUALITY MANAGEMENT at URBAN REGIONAL and GLOBAL SCALES 4 International and IUAPPA Regional Conference,10-13 September 2012 Istanbul-Turkey

WHERE Monitoring sites Rural site Plaine of Aosta Aosta urban area Rural site Lower Valley

Air ambient monitoring sites Roof deposimeter Stack emissions Plouves Dora Supermaket Industrial Area

STACK EMISSIONS

DIFFUSE EMISSIONS

TO THE STACK PRIMARY COLLECTION SYSTEM EAF PRIMARY COLLECTION SYSTEM AOD TO THE STACK GASES (Ar. O2) EAF = Electric Arc Furnace AOD = Argon Oxygen Decarburization Electric steelmaking emissions can be distinguished in primary and secondary emissions Primary emissions are derived from operations carried out at high temperatures as melting of scrap (in EAF) and refining of molten steel (in AOD)

Secondary emissions are derived from production steps such as: furnace charging de-slagging liquid steel transfers handling of additives TO THE STACK SECONDARY COLLECTION SYSTEM DUST, FUMES SCRAP, LIME, COAL SLAG MOLTEN STEEL

ROOF OF THE BUILDING DEPOSIMETER FABRIC FILTER DIFFUSE EMISSIONS FABRIC FILTER FABRIC FILTER EAF AOD GASES (Ar. O2) Off-gases extraction system of Aosta steel mill

DIFFUSE EMISSIONS MONITORING BY DEPOSITION SAMPLING SECONDARY HOODS DEPOSIMETER

ROOF OF THE STEEL MILL BUILDING SUPERMARKET SITE

STACK EMISSIONS 90% of the dust comes from melting and refining processes (container is closed) at high temperature (>1600 C) Zn and Fe are volatilized and oxidized Particles size distribution: 85% is < 10 µm ~100% of dust emissions is collected and treated by fabric filters DIFFUSE EMISSIONS Furnace charging, tapping of molten steel, deslagging (container is opened) Layer of slag in the surface of melt Emission of coarse particles with slag composition Diffuse emissions are not collected and treated Stack emissions consist mainly of PM10 particles composed mainly by zinc and iron oxydes Diffuse emissions consist mainly of coarse particles with the same composition of the slag

The environmental monitorings were conducted by ARPA Valle d Aosta (Regional Agency of Environmental Protection) and are referred to the years from 2008 until 2011.. The temporal coverage of the series extended to 100% of the considered years. Stack and diffuse emissions data were carried out within the integrated pollution prevention and control (IPPC) permit in the same years. PM10 and metals determinations in ambient air quality monitoring have been performed according to the EU Directive 2004/107/EC and UNI EN 14902-2005. Measurements of metals in stack emissions have been carried out according to the UNI EN 13284-1 method. Monitoring of total depositions has been conducted following the Italian laws and regulations (National Institute of Health, 2006) according to EU Directive 2004/107/EC. Total depositions are determined as sum of dry and wet fractions collected by passive exposure of a HDPE bottle/cylindrical funnel system with standardised dimensions, for one month exposure time. The deposited samples are filtrated, then both the particulate matter collected on filter and the filtrate are processed and carried out according to UNI EN 14902-2005 method.

PM10 Distribution of metals content (% on weight) in Stack Emissions and PM10 with respect to the sum of Cr, Ni, Mn, Zn and Fe (divided by 5 for a better reading) 60% 50% 40% Stack Emissions PM10 Industrial Area DEPOSITIONS Distribution of metals content (% on weight) in depositions with respect to the sum of Cr, Ni, Mn, Zn and Fe (divided by 5 for a better reading) Comparison between metal slag composition and the fingerprint of depositions of the roof of the steel mill building 60% 50% 40% 60% Roof Building Steel Mill Slag Composition 50% 40% Roof Building Steel Mill Industrial Area Supermarket Deposition 30% 30% 30% 20% 20% 20% 10% 10% 10% 0% 0% 0% Cr Ni Mn Cr Ni Mn Fe/5 Zn Cr Ni Fe/5 Mn Fe/5 Zn Zn

(µg m -2 d -1 ) PM10 Depositions 25 250 ng/m 3 20 15 10 Aosta Plaine of Aosta Lower Valley Rural Area 200 150 100 Aosta Plaine of Aosta Lower Valley Rural Area 5 50 0 Cr Ni Pb 0 Cr Ni Pb Zn

Milano Brescia Bolzano Verona Venezia Padova Udine Parma Perugia Roma Torino Aosta Urban Area Aosta Industrial Area ng/m³ 22 20 18 16 LIMIT VALUE dir. 2008/50/EC Aosta industrial area 14 12 10 8 6 Other italian cities Aosta Urban Area 4 2 0

80 223 70 68 60 µg m -2 d -1 50 40 30 20 10 0 4,51 9,3 8,5 9,9 4,19 STANDARD LEVEL GERMANY (TA LUFT) 11 4,3 5 0,03 2,3 22 5

Chemical characterization of metal content of stack and diffuse emissions of the steel mill allowed to determine two different fingerprints referable to primary and secondary emissions of steelmaking processes respectively Fine particles (PM10) disperse uniformly along the urban area and the Plaine of Aosta Cr and Ni content in PM10 in these areas are determined by steel mill primary emissions, and result significantly higher respect to other Italian cities. Conversely, in the Lower Valley, metals levels in PM10 are comparable with rural areas. Coarse particles from diffuse emissions determine critical levels of deposition of Cr and Ni in urban area, comparable with levels measured near metal processing plants and higher with respect to TALuft Germany standard values. Taking into account these results, appropriate management and technical measures should be applied to prevent diffuse emissions and to reduce stack emissions from steelmaking process.