Oleum (30%) (made by double contact process of sulfur)

Process description: The double contact process of sulfur produces the main product oleum (30%). For this purpose, the process consumes caustic soda (50%), sulfur, hydrochloric acid, and boiler feedwater. Utilities consumed comprise cooling water, process water, unspecific inorganic chemical, cement, and disposal of cement. Additionally, the process produces electricity as a utility by-product. The multifunctionality problem for the utility by-product is solved by system expansion via the avoided burden approach. Dataset type is technology-specific (extension layer). Allocation type is no allocation needed in this unit process. In case of energy co-production, allocation via avoided burden is applied for the co-produced energy. CAS RN is 8014-95-7. All datasets are based on the attributional LCA approach and the methodology defined in the cm.chemicals methodology document. The fossil emissions value is negative as it uses a systems-expansion approach that creates a credit for the use of a byproduct as a low-carbon substitute input to another process. For more details see the methodology.