Development of low-cost video emissions monitoring technique for aluminum smelting applications

Abstract

Aluminum smelting plants emit gaseous and particulate fluoride, sulfur dioxide (SO2), carbon oxides (CO and CO2), perfluorocarbons (CF4 and C2F6), and other by-products of aluminum electrolysis processes. Potroom fugitive emissions intensity for some of these pollutants (most notably, fluorides) is strongly correlated with potroom work activities and work practices (e.g., anode change operations, metal tapping practices, pot hood placement, etc.). Therefore, work practice standardization and potroom personnel education regarding the impact of their day-to-day activities on smelter emissions are important components of pollution control and prevention strategy. This work introduces a low-cost video emissions monitoring technique utilized at Alcoa that allows overlaying real-time emissions measurements (e.g., HF, SO2, dust, etc.) on video recordings of specific work activities. The developed capability is used to more effectively and uniformly communicate the impact of work practices on plant environmental performance. Specific examples of high-impact work practices are presented and discussed.