Large Volume Inorganic Chemicals - Ammonia ... - ammk-rks.net

Chapter 44.2.3.6 Other raw gas sourcesA variety of gases containing sulphur can be used directly or after suitable processing as rawgases to produce H 2 SO 4 . These include:• various gases arising from combustion or catalytic conversion of H 2 S and/or CS 2 or COSExamples are H 2 S rich tail gases from coke ovens, synthesis gas production, gasifiers andHDS units at refineries, tail gases from Claus units or the manufacture of viscose. Theresulting SO 2 raw gases also contain water, which requires drying prior to H 2 SO 4 productionor specific wet catalysis processes (see Sections 4.4.8 and 4.4.9).• flue-gases from combustion of fuels containing sulphur [10, European Commission, 2005]One example is the “Wellman-Lord” process that removes SO 2 from flue-gases and yieldsan SO 2 rich gas for H 2 SO 4 production. The process is based on absorption and desorption ofSO 2 in NaSO 3 solutions.Another example is the “Bergbau-Forschung” or “activated carbon” process, also forremoving SO 2 from flue-gases. The process is based on adsorption and desorption of SO 2 onactivated carbon and yields a SO 2 /steam mixture, which is used for the downstream wetcatalysis H 2 SO 4 plant (see Sections 4.4.8 and 4.4.9).• gases containing up to 90 % SO 2 from the production of organic compounds such assulphonates or sulphites can also be used, after the removal of organic compounds, as asource of SO 2 .In these cases, the driving force for the production of H 2 SO 4 can be understood as the recoveryof sulphur compounds from tail gases or as emission abatement technique.Large Volume Inorganic Chemicals – Ammonia, Acids and Fertilisers 159