Major Reduction of the Environmental Footprint in Non-Ferrous Concentrate Drying

摘要

Non-ferrous metal concentrates contain typically 7 - 12 % water when received at the smelter. Removal of this water prior to smelting is always economically feasible because unnecessary heating of vapor (from 100 °C to 1,200 °C) can thus be eliminated. This results in major reduction in CO_2 emission.The next step to further improve the energy efficiency, and simultaneously cut emission is to select modern technology for the drying process. Consequently, all CO_2 emission will be completely eliminated (typically from 30,000 - 50,000 tonnes per year down to 0 tpy), SO_2 emission will be negligible (down by over 99.9+ %) and NO_x emission will be complete eliminated.Replacing conventional direct heated drying technology with modern indirect steam drying brings, in addition to dramatic emission reduction, additional savings due to further improved energy efficiency. Direct energy savings count for 900 - 1,300 MJ/t_(H2O), which depending on the concentrate feed rate, its moisture content and price of energy is worth 1 - 3 MEUR every year. Furthermore, in addition to energy savings, other operational expenses can also be cut by another 1-3 MEUR resulting in combined 2-6 MEUR direct savings annually in operational expenses. Sustainability is the key issue today in process industry. Kumera Steam Dryer is already recognized as a symbol of the energy saving and emission-free equipment for non-ferrous metallurgical industry world-wide. Major savings together with significant emission reduction are readily available by proper dryer technology selection for various non-ferrous metal concentrates, like copper, nickel, lead, zinc and complex concentrates.