title: Design of a continuous process setup for precipitated calcium carbonate production from steel converter slag.
abstract: A mineral carbonation process "slag2PCC" for carbon capture, utilization, and storage is discussed. Ca is extracted from steel slag by an ammonium salt solvent and carbonated with gaseous CO2 after the separation of the residual slag. The solvent is reused after regeneration. The effects of slag properties such as the content of free lime, fractions of Ca, Si, Fe, and V, particle size, and slag storage on the Ca extraction efficiency are studied. Small particles with a high free-lime content and minor fractions of Si and V are the most suitable. To limit the amount of impurities in the process, the slag-to-liquid ratio should remain below a certain value, which depends on the slag composition. Also, the design of a continuous test setup (total volume ∼75 L) is described, which enables quick process variations needed to adapt the system to the varying slag quality. Different precipitated calcium carbonate crystals (calcite and vaterite) are generated in different parts of the setup.
authors.affiliation: Thermal and Flow Engineering Laboratory, Åbo Akademi University, Piispankatu 8, FI-20500 Turku (Finland). hmattila@abo.fi.
authors.forename: Hannu-Petteri
authors.initials: HP
authors.lastname: Mattila
authors.forename: Ron
authors.initials: R
authors.lastname: Zevenhoven
mesh_terms: D064751:Ammonium Compounds / Q000737:chemistry; D002119:Calcium Carbonate / Q000737:chemistry* / Q000302:isolation & purification*; D005591:Chemical Fractionation / Q000295:instrumentation / Q000379:methods*; D011232:Chemical Precipitation; D007220:Industrial Waste / Q000032:analysis; D010316:Particle Size; D013232:Steel / Q000737:chemistry*
chemical_list: D064751:Ammonium Compounds; D007220:Industrial Waste; D013232:Steel; D002119:Calcium Carbonate
keywords: calcium; carbon storage; environmental chemistry; industrial chemistry; waste prevention