PM_2.5 Emissions from Aluminum Smelters: Coefficients and Environmental Impact

Abstract

From 2004 to 2009, aiming to better understand implications for its smelters, Rio Tinto Alcan conducted a detailed study of PM 2.5 and PM 10 (particulate matter [PM] Յ 2.5 and 10 m in aerodynamic diameter, respectively) in its facilities. This involved a two-level study: part 1, emission quantification; and part 2, assessment of aluminum smelter contribution to the surrounding environment. In the first part, U.S. Environmental Protection Agency Other Test Method (OTM) OTM27 and OTM28 are assessed as relevant and efficient methods for measuring fine particle emissions from aluminum smelter stacks. Rio Tinto Alcan has also developed a safe and robust method called CYCLEX to measure PM 2.5 and condensable particulate matter (CPM) at the roof vents of potrooms. This work aims to determine the PM 2.5 emission coefficients of 17, 55, and 417 g⅐t Ϫ1 of aluminum produced (including CPM) in anode baking furnace exhaust (fume treatment center), at potroom scrubber stacks (gas treatment centers), and at potroom roof vents, respectively. Results indicate that roof vents are the primary PM 2.5 emitters (85% of all smelter emissions) and that 71% of all smelter PM 2.5 comes from CPM. In the second part, preliminary inorganic speciation studies are conducted by scanning electron microscopy-energy-dispersive X-ray analysis and by isotopic ratios to track smelter emissions to their surrounding environment. This paper releases the first speciation results for an aluminum smelter, and the preliminary isotopic ratio study indicates a 3% impact in terms of PM 2.5 emissions for a representative smelter in an urban area.

Systematic review of potential health risks posed by pharmaceutical, occupational and consumer exposures to metallic and nanoscale aluminum, aluminum oxides, aluminum hydroxide and its soluble salts

“…Boullemant (2011) compared collection methods used to capture total particulate matter (PM total = PM > 0.3 mm plus condensables), PM 10 and PM 2.5 in Al smelter emissions (e.g., anode baking furnace exhaust, potroom scrubber stacks, and potroom roof vents). Two primary Al smelters (both using prebake technologies) with different production rates (190 and 420 kt/year) were studied.…”

Community Health Risk Assessment of Primary Aluminum Smelter Emissions

“…The more urban the setting and the more densely inhabited and industrialized, the more difficult that task will be. Some, like Boullemant, 43 have been able to use novel approaches using isotope tracing to calculate the proportion of community PM 2.5 that originated from the anodes of the local smelter, but such technical aids are the exception.…”

“…Estimated smelter contribution = 3%. 43 **Estimate based on the assumption that fluorides represent 50% of a modern smelter air emissions. Furthermore, from the work of Boullemant, 43 PM 2.5 emission from a modern primary aluminum smelter represents 3% of the total concentration of PM 2.5 in urban air.…”

A New Method for Estimation of Emissions and Sources of Measurements Error in the Silicon Refining Process

“…The industry is subjected to extensive regulations with regard to these emissions-both in terms of outdoor and indoor environment-and in particular emissions containing toxic compounds, heavy metals, or greenhouse gases. 1,2 Furthermore, the health risks associated with the dust and fumes from the smelting and foundry industries in general, and the silicon and ferro-silicon industry in particular, are well documented. [3][4][5][6][7] The adverse health effects caused by long-term exposure and inhalation of fume are numerous and the workers are at risk of developing respiratory problems, including chronic obstructive pulmonary disease (COPD).…”

“…1,13,14 The fuming mechanisms in silicon production have been studied 15,16 and some problems of the fugitive emissions have been documented with respect to the plant and local community. 17 The elemental distributions in silicon and ferrosilicon production have been studied previously with respect to the electric furnace operation.…”