The MECS® metallurgical process is based on years of experience in ore and metal process design. We provide metallurgical plants around the world with technologies that can treat off-gas with high levels of impurity including arsenic, fluorides and mercury.
Off-gas from essentially any continuous or semi-continuous metallurgical process that contains SO2 gas is pulled through the primary MECS® DynaWave® reverse jet scrubber, where it is cleaned and cooled to its adiabatic saturation temperature by recirculation of weak acid. Next, the gas is cooled in the high-efficiency MECS® ZeCor® tower, to a point where the moisture level is reduced to the amount required in the product acid. Depending on the level of impurities in the feed gas, another DynaWave® jet scrubber may be used. The final stage of gas cleaning is a MECS® WESP, which removes both liquid and solid particulate matter, to prevent corrosion and fouling in the acid plant. The gas is then pulled through the high-efficiency ZeCor® drying tower, where remaining water vapor is removed. A MECS® Brink® mist eliminator provides efficient acid mist removal for the protection of the main compressor. The dry, clean gas is then compressed and introduced to the converter system.
In the contact section of the plant, the gas flows through three passes of MECS® GEAR™ and Cesium Catalyst, as well as their respective cooling equipment, and is then absorbed with 98% sulfuric acid (H2SO4) in the Interpass Absorbing Tower. The lean SO2 gas flows through another Brink® Mist Eliminator to remove fine mist particles, protecting downstream equipment. The clean gas is then reheated and enters the converter to complete the fourth conversion pass of SO2 to SO3 using MECS® Super Cesium Catalyst SCX-2000, to achieve the highest possible conversion. The resulting SO3 is absorbed in 98% H2SO4 in the ZeCor® Final Absorbing Tower. Brink® Mist Eliminators are installed in the final tower to ensure the stack gas will meet acid mist environmental regulations.
By using this combination of metallurgical process technologies, non-ferrous metal producers will not only be able to reduce emission levels as required, but also cut energy and water use while optimizing equipment utilization. Among the adopters of the MECS® metallurgical sulfuric acid process technology is the world’s largest copper producer, Codelco.