Table 5 Summary of mercury-specific control techniques for the non-ferrous metal smelting and roasting processes (typical emission performance is shown and may not be demonstrative of all possible situations)38,41 () a Performance data on data for Boliden’s Rönnskärsverken Copper-Lead-Zinc Smelter, as reported in Mercury control Description Typical performance Advantages/comments Disadvantages technique (mercury removal efficiency) a Boliden-Norzink Based on a wet scrubber using the 99.7% Widely demonstrated Chlorine gas handling reaction between mercury(II) inlet concentration of ~ 9900 Calomel handling – chloride and mercury to form g/m3 Calomel disposal as hazardous waste mercury(I) chloride (calomel), 74% which precipitates from the liquor. inlet concentration 51 g/m3 – Selenium filters The selenium filter consists of a 95% Especially suited to low Limited inlet mercury concentration porous inert material soaked with inlet concentration 1000 mercury concentrations in the Spent filter requires environmentally – selenious acid which is then dried g/m3 gas sound disposal to precipitate red amorphous 71% selenium. The red amorphous inlet concentration 42 g/m3 Successful installation at – selenium reacts with the mercury in metallurgical plants the gas to form HgSe. Activated carbon is well known for 97% Sulfur-impregnated activated Spent carbon requires disposal in landfill Activated carbon filter beds its adsorption properties. For the inlet concentration 1,200 carbon is commercially – adsorption of mercury, activated g/m3 available carbon can normally adsorb 10-12 93% Removes Hg0 and other per cent of its own weight. inlet concentration 37 g/m3 species – Low potential for leaching of mercury from spent carbon DOWA Based on the adsorption of mercury 97% Not widely used onto pumice stones coated with inlet concentration 50 g/m3 Mercury sulfide disposal as hazardous – lead sulfide waste 88% inlet concentration 11 g/m3 – Jerritt Based on conversion of elemental 99.97% Very high mercury removal By product disposal consistent with other mercury to mercury (II) chloride by efficiency relevant articles of the Convention reaction with dissolve chlorine Cl2
Table 5 Summary of mercury-specific control techniques for the non-ferrous metal smelting and roasting processes (typical emission performance is shown and may not be demonstrative of all possible situations)38,41 () Mercury control technique Description Typical performance (mercury removal efficiency) a Advantages/comments Disadvantages Boliden-Norzink Based on a wet scrubber using the reaction between mercury(II) chloride and mercury to form mercury(I) chloride (calomel), which precipitates from the liquor. 99.7% – inlet concentration of ~ 9900 g/m3 74% – inlet concentration 51 g/m3 Widely demonstrated Chlorine gas handling Calomel handling Calomel disposal as hazardous waste Selenium filters The selenium filter consists of a porous inert material soaked with selenious acid which is then dried to precipitate red amorphous selenium. The red amorphous selenium reacts with the mercury in the gas to form HgSe. 95% – inlet concentration 1000 g/m3 71% – inlet concentration 42 g/m3 Especially suited to low mercury concentrations in the gas Successful installation at metallurgical plants Limited inlet mercury concentration Spent filter requires environmentally sound disposal Activated carbon filter beds Activated carbon is well known for its adsorption properties. For the adsorption of mercury, activated carbon can normally adsorb 10-12 per cent of its own weight. 97% – inlet concentration 1,200 g/m3 93% – inlet concentration 37 g/m3 Sulfur-impregnated activated carbon is commercially available Removes Hg0 and other species Low potential for leaching of mercury from spent carbon Spent carbon requires disposal in landfill DOWA Based on the adsorption of mercury onto pumice stones coated with lead sulfide 97% – inlet concentration 50 g/m3 88% – inlet concentration 11 g/m3 Not widely used Mercury sulfide disposal as hazardous waste Jerritt Based on conversion of elemental mercury to mercury (II) chloride by reaction with dissolve chlorine Cl2 99.97% Very high mercury removal efficiency By product disposal consistent with other relevant articles of the Convention a Performance data on data for Boliden’s Rönnskärsverken Copper-Lead-Zinc Smelter, as reported in
BATBEP_nonferrous.docx