Dispersion and stack height estimates for a planned aluminium smelter in Reyðarfjördur, Iceland. Fume treatment plant of the anode-baking furnace.

NILU has carried out dispersion calculations for three different stack heights (28, 40 and 50 m) of the Fume treatment plant of a planned aluminium smelter in Reyðarfjördur. Two emission alternatives were considered: for a production of 280 000 and of 420 000 tons of aluminium per year. The maximum estimated concentrations drop drastically with an increase of the stack height from 28 to 40 m, especially near the source and under high wind speeds. NILU recommends that the FTC stack is at least 40 m high, in order to avoid trapping of the plume in the cavity zone of adjacent buildings and improve the ground level concentrations near the source. For a stack height of 40 m, the calculated maximum SO2 hourly concentration is 200 μg/m^3 for all meteorological conditions and bigger distances than 500 m from the source, considering the contribution from FTC.