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Full-Text Articles in Engineering
Co2 Energy Reactor – Integrated Mineral Carbonation: Perspectives On Lab-Scale Investigation And Products Valorization, Rafael M. Santos, Pol C. M. Knops, Keesjan L. Rijnsburger, Yi Wai Chiang
Co2 Energy Reactor – Integrated Mineral Carbonation: Perspectives On Lab-Scale Investigation And Products Valorization, Rafael M. Santos, Pol C. M. Knops, Keesjan L. Rijnsburger, Yi Wai Chiang
Faculty Publications and Scholarship
To overcome the challenges of mineral CO2 sequestration, Innovation Concepts B.V. is developing a unique proprietary gravity pressure vessel (GPV) reactor technology and has focussed on generating reaction products of high economic value. The GPV provides intense process conditions through hydrostatic pressurization and heat exchange integration that harvests exothermic reaction energy, thereby reducing energy demand of conventional reactor designs, in addition to offering other benefits. In this paper, a perspective on the status of this technology and outlook for the future is provided. To date, laboratory-scale tests of the envisioned process have been performed in a tubular “rocking autoclave” reactor. …
Nickel Extraction From Olivine: Effect Of Carbonation Pre-Treatment, Rafael M. Santos, Aldo Van Audenaerde, Yi Wai Chiang, Remus I. Iacobescu, Pol Knops, Tom Van Gerven
Nickel Extraction From Olivine: Effect Of Carbonation Pre-Treatment, Rafael M. Santos, Aldo Van Audenaerde, Yi Wai Chiang, Remus I. Iacobescu, Pol Knops, Tom Van Gerven
Faculty Publications and Scholarship
In this work, we explore a novel mineral processing approach using carbon dioxide to promote mineral alterations that lead to improved extractability of nickel from olivine ((Mg,Fe)2SiO4). The precept is that by altering the morphology and the mineralogy of the ore via mineral carbonation, the comminution requirements and the acid consumption during hydrometallurgical processing can be reduced. Furthermore, carbonation pre-treatment can lead to mineral liberation and concentration of metals in physically separable phases. In a first processing step, olivine is fully carbonated at high CO2 partial pressures (35 bar) and optimal temperature (200 °C) with the addition of pH buffering …
Distinguishing Between Carbonate And Non-Carbonate Precipitates From The Carbonation Of Calcium-Containing Organic Acid Leachates, Rafael M. Santos, Yi Wai Chiang, Jan Elsen, Tom Van Gerven
Distinguishing Between Carbonate And Non-Carbonate Precipitates From The Carbonation Of Calcium-Containing Organic Acid Leachates, Rafael M. Santos, Yi Wai Chiang, Jan Elsen, Tom Van Gerven
Faculty Publications and Scholarship
Two organic acids were trialled for the extraction of calcium from steelmaking blast furnace slag for the purpose of precipitated calcium carbonate (PCC) production: succinic and acetic acids. While the leaching performance of succinic acid was superior, carbonation of its leachate did not result in the production of PCC, but rather the precipitation of calcium succinate, and only after the use of pH buffering agents (sodium hydroxide or bicarbonate). In contrast, carbonation of the acetic acid leachate resulted in the production of PCC, also with the aid of buffering agents. This discrepancy highlights the need for a combination of chemical, …
Towards Zero-Waste Mineral Carbon Sequestration Via Two-Way Valorization Of Ironmaking Slag, Yi Wai Chiang, Rafael M. Santos, Jan Elsen, Boudewijn Meesschaert, Johan A. Martens, Tom Van Gerven
Towards Zero-Waste Mineral Carbon Sequestration Via Two-Way Valorization Of Ironmaking Slag, Yi Wai Chiang, Rafael M. Santos, Jan Elsen, Boudewijn Meesschaert, Johan A. Martens, Tom Van Gerven
Faculty Publications and Scholarship
A three-stage process was developed to transform blast furnace slag (BFS) into two valuable products: precipitated calcium carbonate (PCC) and zeolitic materials. The conceptualized process aims to simultaneously achieve sustainable CO2 sequestration and solid waste elimination. Calcium is first selectively extracted by leaching with an organic acid, followed by carbonation of the leachate to precipitate CaCO3. In parallel, the hydrothermal conversion of the extracted solid residues in alkali solution induces the dissolution/precipitation mechanism that leads to the formation of micro- and meso-porous zeolitic materials. Leaching selectivity was identified as a key factor in the valorization potential of both products. Acetic …
Chemoorganotrophic Bioleaching Of Olivine For Nickel Recovery, Yi Wai Chiang, Rafael M. Santos, Aldo Van Audenaerde, Annick Monballiu, Tom Van Gerven, Boudewijn Meesschaert
Chemoorganotrophic Bioleaching Of Olivine For Nickel Recovery, Yi Wai Chiang, Rafael M. Santos, Aldo Van Audenaerde, Annick Monballiu, Tom Van Gerven, Boudewijn Meesschaert
Faculty Publications and Scholarship
Bioleaching of olivine, a natural nickel-containing magnesium-iron-silicate, was conducted by applying chemoorganotrophic bacteria and fungi. The tested fungus, Aspergillus niger, leached substantially more nickel from olivine than the tested bacterium, Paenibacillus mucilaginosus. Aspergillus niger also outperformed two other fungal species: Humicola grisae and Penicillium chrysogenum. Contrary to traditional acid leaching, the microorganisms leached nickel preferentially over magnesium and iron. An average selectivity factor of 2.2 was achieved for nickel compared to iron. The impact of ultrasonic conditioning on bioleaching was also tested, and it was found to substantially increase nickel extraction by A. niger. This is credited to an enhancement …
Effect Of Accelerated Carbonation On Aod Stainless Steel Slag For Its Valorisation As A Co2-Sequestering Construction Material, Muhammad Salman, Özlem Cizer, Yiannis Pontikes, Rafael M. Santos, Ruben Snellings, Lucie Vandewalle, Bart Blanpain, Koen Van Balen
Effect Of Accelerated Carbonation On Aod Stainless Steel Slag For Its Valorisation As A Co2-Sequestering Construction Material, Muhammad Salman, Özlem Cizer, Yiannis Pontikes, Rafael M. Santos, Ruben Snellings, Lucie Vandewalle, Bart Blanpain, Koen Van Balen
Faculty Publications and Scholarship
Non-stabilized Argon Oxygen Decarburisation (AODNS) slag in powdered form was examined for its carbon dioxide sequestration capacity and for its potential utilization in the fabrication of high value building materials. The curing of the sample was carried out in two accelerated carbonation environments: i) in a carbonation chamber, maintained at atmospheric pressure, 22 °C, 5 vol.% CO2 and 80% RH; and ii) in a carbonation reactor, where the CO2 partial pressure (pCO2) and temperature could be further increased. In the carbonation chamber, an average compressive strength of over 20 MPa, on a 64 cm …
Magnesium Chloride As A Leaching And Aragonite-Promoting Self-Regenerative Additive For The Mineral Carbonation Of Calcium-Rich Materials, Rafael M. Santos, Marius Bodor, Paul N. Dragomir, Andreea G. Vraciu, Maria Vlad, Tom Van Gerven
Magnesium Chloride As A Leaching And Aragonite-Promoting Self-Regenerative Additive For The Mineral Carbonation Of Calcium-Rich Materials, Rafael M. Santos, Marius Bodor, Paul N. Dragomir, Andreea G. Vraciu, Maria Vlad, Tom Van Gerven
Faculty Publications and Scholarship
Two approaches for the intensification of the mineral carbonation reaction are combined and studied in this work, namely: (i) the calcium leaching and aragonite promoting effects of magnesium chloride (MgCl2), and (ii) the passivating layer abrasion effect of sonication. The alkaline materials subjected to leaching and carbonation tests included lime, wollastonite, steel slags, and air pollution control (APC) residue. Batch leaching tests were conducted with varying concentrations of additives to determine extraction efficiency, and with varying solids-to-liquid ratios to determine solubility limitations. Aqueous mineral carbonation tests, with and without the use of ultrasound, were conducted applying varying concentrations of magnesium …
Recent Developments And Perspectives On The Treatment Of Industrial Wastes By Mineral Carbonation - A Review, Marius Bordor, Rafael M. Santos, Tom Van Gerven, Maria Vlad
Recent Developments And Perspectives On The Treatment Of Industrial Wastes By Mineral Carbonation - A Review, Marius Bordor, Rafael M. Santos, Tom Van Gerven, Maria Vlad
Faculty Publications and Scholarship
Besides producing a substantial portion of anthropogenic CO2 emissions, the industrial sector also generates significant quantities of solid residues. Mineral carbonation of alkaline wastes enables the combination of these two by-products, increasing the sustainability of industrial activities. On top of sequestering CO2 in geochemically stable form, mineral carbonation of waste materials also brings benefits such as stabilization of leaching, basicity and structural integrity, enabling further valorization of the residues, either via reduced waste treatment or landfilling costs, or via the production of marketable products. This paper reviews the current state-of-the-art of this technology and the latest developments in this field. …
Accelerated Mineral Carbonation Of Stainless Steel Slags For Co2 Storage And Waste Valorization: Effect Of Process Parameters On Geochemical Properties, Rafael M. Santos, Jens Van Bouwel, Ellen Vandevelde, Gilles Mertens, Jan Elsen, Tom Van Gerven
Accelerated Mineral Carbonation Of Stainless Steel Slags For Co2 Storage And Waste Valorization: Effect Of Process Parameters On Geochemical Properties, Rafael M. Santos, Jens Van Bouwel, Ellen Vandevelde, Gilles Mertens, Jan Elsen, Tom Van Gerven
Faculty Publications and Scholarship
This work explores the mineral carbonation of stainless steel slags in search for a technically and economically feasible treatment solution that steers these waste residues away from costly disposal in landfills and into valuable applications. Argon Oxygen Decarburization (AOD) and Continuous Casting (CC) slags prove ideal for mineral carbonation as their powdery morphology forgoes the need for milling and provides sufficient surface area for high reactivity towards direct aqueous carbonation. Experiments were undertaken using two methodologies: unpressurized thin-film carbonation, and pressurized slurry carbonation. The influence of process parameters (temperature, CO2 partial pressure, time, solids loading) on the slag carbonation conversion …
Ultrasound-Intensified Mineral Carbonation, Rafael M. Santos, Davy Francois, Gilles Mertens, Jan Elsen, Tom Van Gerven
Ultrasound-Intensified Mineral Carbonation, Rafael M. Santos, Davy Francois, Gilles Mertens, Jan Elsen, Tom Van Gerven
Faculty Publications and Scholarship
Several aspects of ultrasound-assisted mineral carbonation were investigated in this work. The objectives were to intensify the CO2 sequestration process to improve reaction kinetics and maximal conversion. Stainless steel slags, derived from the Argon Oxygen Decarburization (AOD) and Continuous Casting / Ladle Metallurgy (CC/LM) refining steps, were used for assessing the technical feasibility of this concept, as they are potential carbon sinks and can benefit from reduction in alkalinity (pH) by mineral carbonation. Ultrasound was applied by use of an ultrasound horn into the reaction slurry, where mineral carbonation reaction took place at 50 oC for up to …
Stabilization Of Basic Oxygen Furnace Slag By Hot-Stage Carbonation Treatment., Rafael M. Santos, Da Ling, Amin Sarvaramini, Muxing Guo, Jan Elsen, Faïçal Larachi, Georges Beaudoin, Bart Blanpain, Tom Van Gerven
Stabilization Of Basic Oxygen Furnace Slag By Hot-Stage Carbonation Treatment., Rafael M. Santos, Da Ling, Amin Sarvaramini, Muxing Guo, Jan Elsen, Faïçal Larachi, Georges Beaudoin, Bart Blanpain, Tom Van Gerven
Faculty Publications and Scholarship
Treatment and disposal of Basic Oxygen Furnace (BOF) slag, a residue of the steel production process characterized by high basicity and propensity for heavy metal leaching, is a costly burden on metallurgical plants; a sustainable valorization route is desired. The stabilization of BOF slag utilizing hot-stage carbonation treatment was investigated; this approach envisions carbonation during the hot-to-cold pathway followed by the material after the molten slag is poured and solidified. Three experimental methodologies were employed: (i) in-situ thermogravimetric analyzer (TGA) carbonation was used to assess carbonation reaction kinetics and thermodynamic equilibrium at high temperatures; (ii) pressurized basket reaction carbonation was …
Synthesis Of Pure Aragonite By Sonochemical Mineral Carbonation., Rafael M. Santos, Pieter Ceulemans, Tom Van Gerven
Synthesis Of Pure Aragonite By Sonochemical Mineral Carbonation., Rafael M. Santos, Pieter Ceulemans, Tom Van Gerven
Faculty Publications and Scholarship
The objective of this work was to promote the formation of the aragonite polymorph of calcium carbonate, which has some valuable applications in industry, via the mineral carbonation route. The combination of ultrasound with magnesium ions promoted the formation of pure aragonite crystals at optimum conditions. It was possible to synthesize high purity aragonite precipitates at temperatures ranging from 24 oC to 70 oC, with the resulting powders possessing varying particle size distributions (from sub-micron up to 20 μm) and crystal morphologies (from acicular needles to novel hubbard squash-like particles). Several process parameters were found to influence the …
Process Intensification Routes For Mineral Carbonation, Rafael M. Santos, Tom Van Gerven
Process Intensification Routes For Mineral Carbonation, Rafael M. Santos, Tom Van Gerven
Faculty Publications and Scholarship
Mineral carbonation is a realistic route for capture and storage of carbon dioxide. The principal advantages of this approach are the chemical stability and storage safety of mineral carbonates, the opportunities for process integration available, and the potential for conversion of low-value materials into useful products. In this work the valorisation of alkaline waste materials from thermal processes by mineral carbonation utilizing intensified and integrated mineral carbonation routes is explored. Process intensification is the chemical engineering of the 21st century, and aims at providing the paradigm-shifting techniques that will revolutionize the industry. The combination of process intensification and process integration …