Off gas from essentially any continuous or semi-continuous process that contains SO2 gas is pulled through the primary DynawaveŽ Reverse Jet Scrubber where it is cleaned and cooled to its adiabatic saturation temperature by recirculation weak acid. Next, the gas is cooled in the gas-cooling tower, to a point where the moisture level is reduced to the amount required in the product acid. Next, depending on the level of impurities in the feed gas, a final Dynawave Jet Scrubber may be used. The final stage of gas cleaning is a wet electrostatic precipitator (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-drying tower where the remaining water vapor is removed. A 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.
SO3 Absorption
After passing through the first three layers of MECS LP and Cesium catalyst, SO3 rich gas is cooled and absorbed with 98% sulfuric acid (H2SO4) in the Interpass absorption tower. The lean SO2 gas flows through a Brink Mist Eliminator to remove fine mist particles, thereby protecting downstream equipment. The clean gas is then reheated and enters the converter to complete the conversion of SO2 to SO3. The SO3 formed is absorbed in 98% H2SO4 in the final absorbing tower. Brink Mist Eliminators are installed in the final tower to insure the stack gas will meet environmental regulations on acid mist.
