Mineral Carbonation of Basic Oxygen Furnace Slags
Mineral carbonation is a method in carbon capture and utilization (CCU) in which carbon dioxide reacts with natural or synthetic mineral phases to form carbonates. In this study, BOF slag consisting of alite, Ca<sub>3</sub>SiO<sub>5</sub>, belite, Ca<sub>2</sub>Si...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-11-01
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| Series: | Recycling |
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| Online Access: | https://www.mdpi.com/2313-4321/7/6/84 |
| _version_ | 1797455525841993728 |
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| author | Daniel Vollprecht Dominik Wohlmuth |
| author_facet | Daniel Vollprecht Dominik Wohlmuth |
| author_sort | Daniel Vollprecht |
| collection | DOAJ |
| description | Mineral carbonation is a method in carbon capture and utilization (CCU) in which carbon dioxide reacts with natural or synthetic mineral phases to form carbonates. In this study, BOF slag consisting of alite, Ca<sub>3</sub>SiO<sub>5</sub>, belite, Ca<sub>2</sub>SiO<sub>4</sub>, melilite, (Ca,Na)<sub>2</sub>(Mg,Al)<sup>[4]</sup>[Si<sub>2</sub>O<sub>7</sub>], brownmillerite, Ca(Fe,Al)<sub>2</sub>O<sub>5</sub>, calcium ferrite, Ca<sub>2</sub>FeO<sub>4</sub> and Ca-, Mg- and Mn-bearing wuestite, (Mg,Ca,Mn,Fe)O, was crushed into different particle size fractions and exposed over various durations (1 d, 3 d, 9 d, 14 d, 24 d) at a grate to 120 °C hot off-gas with a CO<sub>2</sub> content of 25%. However, the total inorganic carbon (TIC) content never increases above the detection limit of 0.5% throughout the experimental duration. The determination of the carbonation depth using phenolphthalein does not reveal a homogeneous carbonation front, but an irregular carbonation. This observation was confirmed by microprobe analyses using elemental mapping. The solubility of the slag increases with increasing carbonation, e.g., the leachability of sulfate increases from 7.8 to 8270 mg/kg dry matter (DM), and of calcium from 940 to 3860 mg/kg DM. The leaching of environmentally relevant element varies: the leachable concentration of molybdenum increases from 0.017 mg/kg DM to 0.089 mg/kg DM, that of chromium remains constant (ca. 0.05 mg/kg DM) whereas that of vanadium decreases from 1.1 to 0.45 mg/kg. In summary, the chosen carbonation technology must be improved to enhance carbonate yield. |
| first_indexed | 2024-03-09T15:54:35Z |
| format | Article |
| id | doaj.art-82cb8de73a234e9ea4dd9726fe029257 |
| institution | Directory Open Access Journal |
| issn | 2313-4321 |
| language | English |
| last_indexed | 2024-03-09T15:54:35Z |
| publishDate | 2022-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Recycling |
| spelling | doaj.art-82cb8de73a234e9ea4dd9726fe0292572023-11-24T17:43:42ZengMDPI AGRecycling2313-43212022-11-01768410.3390/recycling7060084Mineral Carbonation of Basic Oxygen Furnace SlagsDaniel Vollprecht0Dominik Wohlmuth1Chair of Waste Processing Technology and Waste Management, Montanuniversität Leoben, 8700 Leoben, AustriaVoestalpine Stahl Donawitz GmbH, 8700 Leoben, AustriaMineral carbonation is a method in carbon capture and utilization (CCU) in which carbon dioxide reacts with natural or synthetic mineral phases to form carbonates. In this study, BOF slag consisting of alite, Ca<sub>3</sub>SiO<sub>5</sub>, belite, Ca<sub>2</sub>SiO<sub>4</sub>, melilite, (Ca,Na)<sub>2</sub>(Mg,Al)<sup>[4]</sup>[Si<sub>2</sub>O<sub>7</sub>], brownmillerite, Ca(Fe,Al)<sub>2</sub>O<sub>5</sub>, calcium ferrite, Ca<sub>2</sub>FeO<sub>4</sub> and Ca-, Mg- and Mn-bearing wuestite, (Mg,Ca,Mn,Fe)O, was crushed into different particle size fractions and exposed over various durations (1 d, 3 d, 9 d, 14 d, 24 d) at a grate to 120 °C hot off-gas with a CO<sub>2</sub> content of 25%. However, the total inorganic carbon (TIC) content never increases above the detection limit of 0.5% throughout the experimental duration. The determination of the carbonation depth using phenolphthalein does not reveal a homogeneous carbonation front, but an irregular carbonation. This observation was confirmed by microprobe analyses using elemental mapping. The solubility of the slag increases with increasing carbonation, e.g., the leachability of sulfate increases from 7.8 to 8270 mg/kg dry matter (DM), and of calcium from 940 to 3860 mg/kg DM. The leaching of environmentally relevant element varies: the leachable concentration of molybdenum increases from 0.017 mg/kg DM to 0.089 mg/kg DM, that of chromium remains constant (ca. 0.05 mg/kg DM) whereas that of vanadium decreases from 1.1 to 0.45 mg/kg. In summary, the chosen carbonation technology must be improved to enhance carbonate yield.https://www.mdpi.com/2313-4321/7/6/84BOF slagmineral carbonationcarbon capture and utilization |
| spellingShingle | Daniel Vollprecht Dominik Wohlmuth Mineral Carbonation of Basic Oxygen Furnace Slags Recycling BOF slag mineral carbonation carbon capture and utilization |
| title | Mineral Carbonation of Basic Oxygen Furnace Slags |
| title_full | Mineral Carbonation of Basic Oxygen Furnace Slags |
| title_fullStr | Mineral Carbonation of Basic Oxygen Furnace Slags |
| title_full_unstemmed | Mineral Carbonation of Basic Oxygen Furnace Slags |
| title_short | Mineral Carbonation of Basic Oxygen Furnace Slags |
| title_sort | mineral carbonation of basic oxygen furnace slags |
| topic | BOF slag mineral carbonation carbon capture and utilization |
| url | https://www.mdpi.com/2313-4321/7/6/84 |
| work_keys_str_mv | AT danielvollprecht mineralcarbonationofbasicoxygenfurnaceslags AT dominikwohlmuth mineralcarbonationofbasicoxygenfurnaceslags |