Co2 Sequestration By Ex-situ Mineral Carbonation

Co2 Sequestration By Ex-situ Mineral Carbonation PDF Author: Aimaro Sanna
Publisher: World Scientific
ISBN: 1786341611
Category : Technology & Engineering
Languages : en
Pages : 192

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Book Description
To meet human energy needs, the use of fossil fuels is set to continue well into the second half of the 21st century. In order to avoid irreversible climate change, carbon dioxide capture and storage (CCS) must be integrated into industrial processes. Mineral carbonation (MC) is increasingly seen as an effective technology solution for CCS of CO2. With the potential to sequester billions of tonnes per year, remarkable developments in mineral carbonation technology are taking place, particularly in USA, Australia and the European Union.This book brings together some of the world's leading experts in the field of sequestration to provide a critical assessment of progress to date. Chapters cover the resources available for MC, and also give a critical analysis of the technologies developed for sequestering carbon from industrial and power plants, including the use of the resultant carbonated product. The studies conclude with evaluation of key technical and economic obstacles which need to be addressed for future research, development and application. CO2 Sequestration by Ex-Situ Mineral Carbonation is essential reading for engineers, chemists and materials scientists in graduate or research positions, and for those interested in sustainability, the environment and ecology.

Carbon Dioxide Sequestration by Ex-situ Mineral Carbonation

Carbon Dioxide Sequestration by Ex-situ Mineral Carbonation PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 10

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Book Description
The process developed for carbon dioxide sequestration utilizes a slurry of water mixed with olivine- forsterite end member (Mg2SiO4), which is reacted with supercritical CO2 to produce magnesite (MgCO3). Carbon dioxide is dissolved in water to form carbonic acid, which likely dissociates to H and HCO3−. The H hydrolyzes the silicate mineral, freeing the cation (Mg{sup 2+}), which reacts with the HCO3− to form the solid carbonate. Results of the baseline tests, conducted on ground products of the natural mineral, have demonstrated that the kinetics of the reaction are slow at ambient temperature (22 degrees C) and subcritical CO2 pressures (below 7.4 MPa). However, at elevated temperature and pressure, coupled with continuous stirring of the slurry and gas dispersion within the water column, significant conversion to the carbonate occurs. Extent of reaction is roughly 90% within 24 h, at 185 degrees C and partial pressure of CO2 (P{sub CO{sub 2}}) of 11.6 MPa. Current studies suggest that reaction kinetics can be improved by pretreatment of the mineral, catalysis of the reaction, and/or solution modification. Subsequent tests are intended to examine these options, as well as other mineral groups.

Ex-situ and In-situ Mineral Carbonation as a Means to Sequester Carbon Dioxide

Ex-situ and In-situ Mineral Carbonation as a Means to Sequester Carbon Dioxide PDF Author: William K. O'Connor
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
The U.S. Department of Energy's Albany Research Center is investigating mineral carbonation as a method of sequestering CO2 from coal-fired-power plants. Magnesium-silicate minerals such as serpentine [Mg3Si2O5(OH)4] and olivine (Mg2SiO4) react with CO2 to produce magnesite (MgCO3), and the calcium-silicate mineral, wollastonite (CaSiO3), reacts to form calcite (CaCO3). It is possible to carry out these reactions either ex situ (above ground in a traditional chemical processing plant) or in situ (storage underground and subsequent reaction with the host rock to trap CO2 as carbonate minerals). For ex situ mineral carbonation to be economically attractive, the reaction must proceed quickly to near completion. The reaction rate is accelerated by raising the activity of CO2 in solution, heat (but not too much), reducing the particle size, high-intensity grinding to disrupt the crystal structure, and, in the case of serpentine, heat-treatment to remove the chemically bound water. All of these carry energy/economic penalties. An economic study illustrates the impact of mineral availability and process parameters on the cost of ex situ carbon sequestration. In situ carbonation offers economic advantages over ex situ processes, because no chemical plant is required. Knowledge gained from the ex situ work was applied to long-term experiments designed to simulate in situ CO2 storage conditions. The Columbia River Basalt Group (CRBG), a multi-layered basaltic lava formation, has potentially favorable mineralogy (up to 25% combined concentration of Ca, Fe2+, and Mg cations) for storage of CO2. However, more information about the interaction of CO2 with aquifers and the host rock is needed. Core samples from the CRBG, as well as samples of olivine, serpentine, and sandstone, were reacted in an autoclave for up to 2000 hours at elevated temperatures and pressures. Changes in core porosity, secondary mineralizations, and both solution and solid chemistry were measured.

Carbon Dioxide Sequestration by Direct Mineral Carbonation with Carbonic Acid

Carbon Dioxide Sequestration by Direct Mineral Carbonation with Carbonic Acid PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
The Albany Research Center (ARC) of the U.S. Dept. of Energy (DOE) has been conducting a series of mineral carbonation tests at its Albany, Oregon, facility over the past 2 years as part of a Mineral Carbonation Study Program within the DOE. Other participants in this Program include the Los Alamos National Laboratory, Arizona State University, Science Applications International Corporation, and the DOE National Energy Technology Laboratory. The ARC tests have focused on ex-situ mineral carbonation in an aqueous system. The process developed at ARC utilizes a slurry of water mixed with a magnesium silicate mineral, olivine [forsterite end member (Mg2SiO4)], or serpentine [Mg3Si2O5(OH)4]. This slurry is reacted with supercritical carbon dioxide (CO2) to produce magnesite (MgCO3). The CO2 is dissolved in water to form carbonic acid (H2CO3), which dissociates to H+ and HCO3 -. The H+ reacts with the mineral, liberating Mg2+ cations which react with the bicarbonate to form the solid carbonate. The process is designed to simulate the natural serpentinization reaction of ultramafic minerals, and for this reason, these results may also be applicable to in-situ geological sequestration regimes. Results of the baseline tests, conducted on ground products of the natural minerals, have been encouraging. Tests conducted at ambient temperature (22 C) and subcritical CO2 pressures (below 73 atm) resulted in very slow conversion to the carbonate. However, when elevated temperatures and pressures are utilized, coupled with continuous stirring of the slurry and gas dispersion within the water column, significant reaction occurs within much shorter reaction times. Extent of reaction, as measured by the stoichiometric conversion of the silicate mineral (olivine) to the carbonate, is roughly 90% within 24 hours, using distilled water, and a reaction temperature of 185?C and a partial pressure of CO2 (PCO2) of 115 atm. Recent tests using a bicarbonate solution, under identical reaction conditions, have achieved roughly 83% conversion of heat treated serpentine and 84% conversion of olivine to the carbonate in 6 hours. The results from the current studies suggest that reaction kinetics can be improved by pretreatment of the mineral, catalysis of the reaction, or some combination of the two. Future tests are intended to examine a broader pressure/temperature regime, various pretreatment options, as well as other mineral groups.

A Method for Permanent CO2 Mineral Carbonation

A Method for Permanent CO2 Mineral Carbonation PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
The Albany Research Center (ARC) of the U.S. Department of Energy (DOE) has been conducting research to investigate the feasibility of mineral carbonation as a method for carbon dioxide (CO2) sequestration. The research is part of a Mineral Carbonation Study Program within the Office of Fossil Energy in DOE. Other participants in this Program include DOE?s Los Alamos National Laboratory and National Energy Technology Laboratory, Arizona State University, and Science Applications International Corporation. The research has focused on ex-situ mineral carbonation in an aqueous system. The process developed at ARC reacts a slurry of magnesium silicate mineral with supercritical CO2 to produce a solid magnesium carbonate product. To date, olivine and serpentine have been used as the mineral reactant, but other magnesium silicates could be used as well. The process is designed to simulate the natural serpentinization reaction of ultramafic minerals, and consequently, these results may also be applicable to strategies for in-situ geological sequestration. Baseline tests were begun in distilled water on ground products of foundry-grade olivine. Tests conducted at 150 C and subcritical CO2 pressures (50 atm) resulted in very slow conversion to carbonate. Increasing the partial pressure of CO2 to supercritical (>73 atm) conditions, coupled with agitation of the slurry and gas dispersion within the water column, resulted in significant improvement in the extent of reaction in much shorter reaction times. A change from distilled water to a bicarbonate/salt solution further improved the rate and extent of reaction. When serpentine, a hydrated mineral, was used instead of olivine, extent of reaction was poor until heat treatment was included prior to the carbonation reaction. Removal of the chemically bound water resulted in conversion to carbonate similar to those obtained with olivine. Recent results have shown that conversions of nearly 80 pct are achievable after 30 minutes at test conditions of 155 C and 185 atm CO2 in a bicarbonate/salt solution. The results from the current studies suggest that reaction kinetics can be further improved. Future tests will examine additional pressure/temperature regimes, various pretreatment options, and solution modifications.

Carbon Dioxide Sequestration by Direct Aqueous Mineral Carbonation

Carbon Dioxide Sequestration by Direct Aqueous Mineral Carbonation PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
Carbon dioxide sequestration by an ex-situ, direct aqueous mineral carbonation process has been investigated over the past two years. This process was conceived to minimize the steps in the conversion of gaseous CO2 to a stable solid. This meant combining two separate reactions, mineral dissolution and carbonate precipitation, into a single unit operation. It was recognized that the conditions favorable for one of these reactions could be detrimental to the other. However, the benefits for a combined aqueous process, in process efficiency and ultimately economics, justified the investigation. The process utilizes a slurry of water, dissolved CO2, and a magnesium silicate mineral, such as olivine [forsterite end member (Mg2SiO4)], or serpentine [Mg3Si2O5(OH)4]. These minerals were selected as the reactants of choice for two reasons: (1) significant abundance in nature; and (2) high molar ratio of the alkaline earth oxides (CaO, MgO) within the minerals. Because it is the alkaline earth oxide that combines with CO2 to form the solid carbonate, those minerals with the highest ratio of these oxides are most favored. Optimum results have been achieved using heat pretreated serpentine feed material, sodium bicarbonate and sodium chloride additions to the solution, and high partial pressure of CO2 (PCO2). Specific conditions include: 155?C; PCO2=185 atm; 15% solids. Under these conditions, 78% conversion of the silicate to the carbonate was achieved in 30 minutes. Future studies are intended to investigate various mineral pretreatment options, the carbonation solution characteristics, alternative reactants, scale-up to a continuous process, geochemical modeling, and process economics.

Carbon Dioxide Sequestration by Mineral Carbonation of Iron-bearing Minerals

Carbon Dioxide Sequestration by Mineral Carbonation of Iron-bearing Minerals PDF Author: Kristin D. Lammers
Publisher:
ISBN:
Category :
Languages : en
Pages : 230

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Book Description
Carbon dioxide (CO2) is formed when fossil fuels such as oil, gas and coal are burned in power producing plants. CO2 is naturally found in the atmosphere as part of the carbon cycle, however it becomes a primary greenhouse gas when human activities disturb this natural balanced cycle by increasing levels in the atmosphere. In light of this fact, greenhouse gas mitigation strategies have garnered a lot of attention. Carbon capture, utilization and sequestration (CCUS) has emerged as a possible strategy to limit CO2 emissions into the atmosphere. The technology involves capturing CO2 at the point sources, using it for other markets or transporting to geological formations for safe storage. This thesis aims to understand and probe the chemistry of the reactions between CO2 and iron-bearing sediments to ensure secure storage for millennia. The dissertation work presented here focused on trapping CO2 as a carbonate mineral as a permanent and secure method of CO2 storage. The research also explored the use of iron-bearing minerals found in the geological subsurface as candidates for trapping CO2 and sulfide gas mixtures as siderite (FeCO3) and iron sulfides. Carbon dioxide sequestration via the use of sulfide reductants of the iron oxyhydroxide polymorphs lepidocrocite, goethite and akaganeite with supercritical CO2 (scCO2) was investigated using in situ attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The exposure of the different iron oxyhydroxides to aqueous sulfide in contact with scCO2 at ~70-100 ̊C resulted in the partial transformation of the minerals to siderite (FeCO3). The order of mineral reactivity with regard to siderite formation in the scCO2/sulfide environment was goethite

Carbon Dioxide Sequestration in Cementitious Construction Materials

Carbon Dioxide Sequestration in Cementitious Construction Materials PDF Author: Fernando Pacheco-Torgal
Publisher: Woodhead Publishing
ISBN: 0081024479
Category : Technology & Engineering
Languages : en
Pages : 474

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Book Description
Carbon Dioxide Sequestration in Cementitious Construction Materials provides an updated, state-of-the-art review on the development of cementitious construction materials based on carbon dioxide storage, which will have a major eco-efficient and economic benefit for the construction industry. Key chapters include methods for the assessment of carbon dioxide absorbed by cementitious materials, air and water-based carbon dioxide storage, carbon dioxide storage modeling, carbonation mechanisms, carbon dioxide storage on recycled aggregates, calcium, sodium and magnesium- based binders, properties and the durability of carbon dioxide based concrete. Promotes the importance of CO2 storage in carbonation of these materials, especially reincorporation of CO2 during fabrication Discusses a wide range of cementitious materials with CO2 storage capabilities Features redesign of cementation mechanisms to utilize CO2 during fabrication

Factors Affecting Ex-situ Aqueous Mineral Carbonation Using Calcium and Magnesium Silicate Minerals

Factors Affecting Ex-situ Aqueous Mineral Carbonation Using Calcium and Magnesium Silicate Minerals PDF Author: William K. O'Connor
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
Carbonation of magnesium- and calcium-silicate minerals to form their respective carbonates is one method to sequester carbon dioxide. Process development studies have identified reactor design as a key component affecting both the capital and operating costs of ex-situ mineral sequestration. Results from mineral carbonation studies conducted in a batch autoclave were utilized to design and construct a unique continuous pipe reactor with 100% recycle (flow-loop reactor). Results from the flow-loop reactor are consistent with batch autoclave tests, and are being used to derive engineering data necessary to design a bench-scale continuous pipeline reactor.

Co2 Sequestration By Ex-situ Mineral Carbonation

Co2 Sequestration By Ex-situ Mineral Carbonation PDF Author: Aimaro Sanna
Publisher: World Scientific
ISBN: 1786341611
Category : Technology & Engineering
Languages : en
Pages : 192

View

Book Description
To meet human energy needs, the use of fossil fuels is set to continue well into the second half of the 21st century. In order to avoid irreversible climate change, carbon dioxide capture and storage (CCS) must be integrated into industrial processes. Mineral carbonation (MC) is increasingly seen as an effective technology solution for CCS of CO2. With the potential to sequester billions of tonnes per year, remarkable developments in mineral carbonation technology are taking place, particularly in USA, Australia and the European Union.This book brings together some of the world's leading experts in the field of sequestration to provide a critical assessment of progress to date. Chapters cover the resources available for MC, and also give a critical analysis of the technologies developed for sequestering carbon from industrial and power plants, including the use of the resultant carbonated product. The studies conclude with evaluation of key technical and economic obstacles which need to be addressed for future research, development and application. CO2 Sequestration by Ex-Situ Mineral Carbonation is essential reading for engineers, chemists and materials scientists in graduate or research positions, and for those interested in sustainability, the environment and ecology.

CO2 Sequestration by Ex-situ Mineral Carbonation

CO2 Sequestration by Ex-situ Mineral Carbonation PDF Author: Aimaro Sanna
Publisher:
ISBN: 9781786341600
Category : TECHNOLOGY & ENGINEERING
Languages : en
Pages :

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Book Description


Carbon Dioxide Sequestration by Ex-situ Mineral Carbonation

Carbon Dioxide Sequestration by Ex-situ Mineral Carbonation PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 10

View

Book Description
The process developed for carbon dioxide sequestration utilizes a slurry of water mixed with olivine- forsterite end member (Mg2SiO4), which is reacted with supercritical CO2 to produce magnesite (MgCO3). Carbon dioxide is dissolved in water to form carbonic acid, which likely dissociates to H and HCO3−. The H hydrolyzes the silicate mineral, freeing the cation (Mg{sup 2+}), which reacts with the HCO3− to form the solid carbonate. Results of the baseline tests, conducted on ground products of the natural mineral, have demonstrated that the kinetics of the reaction are slow at ambient temperature (22 degrees C) and subcritical CO2 pressures (below 7.4 MPa). However, at elevated temperature and pressure, coupled with continuous stirring of the slurry and gas dispersion within the water column, significant conversion to the carbonate occurs. Extent of reaction is roughly 90% within 24 h, at 185 degrees C and partial pressure of CO2 (P{sub CO{sub 2}}) of 11.6 MPa. Current studies suggest that reaction kinetics can be improved by pretreatment of the mineral, catalysis of the reaction, and/or solution modification. Subsequent tests are intended to examine these options, as well as other mineral groups.

Ex-situ and In-situ Mineral Carbonation as a Means to Sequester Carbon Dioxide

Ex-situ and In-situ Mineral Carbonation as a Means to Sequester Carbon Dioxide PDF Author: William K. O'Connor
Publisher:
ISBN:
Category :
Languages : en
Pages :

View

Book Description
The U.S. Department of Energy's Albany Research Center is investigating mineral carbonation as a method of sequestering CO2 from coal-fired-power plants. Magnesium-silicate minerals such as serpentine [Mg3Si2O5(OH)4] and olivine (Mg2SiO4) react with CO2 to produce magnesite (MgCO3), and the calcium-silicate mineral, wollastonite (CaSiO3), reacts to form calcite (CaCO3). It is possible to carry out these reactions either ex situ (above ground in a traditional chemical processing plant) or in situ (storage underground and subsequent reaction with the host rock to trap CO2 as carbonate minerals). For ex situ mineral carbonation to be economically attractive, the reaction must proceed quickly to near completion. The reaction rate is accelerated by raising the activity of CO2 in solution, heat (but not too much), reducing the particle size, high-intensity grinding to disrupt the crystal structure, and, in the case of serpentine, heat-treatment to remove the chemically bound water. All of these carry energy/economic penalties. An economic study illustrates the impact of mineral availability and process parameters on the cost of ex situ carbon sequestration. In situ carbonation offers economic advantages over ex situ processes, because no chemical plant is required. Knowledge gained from the ex situ work was applied to long-term experiments designed to simulate in situ CO2 storage conditions. The Columbia River Basalt Group (CRBG), a multi-layered basaltic lava formation, has potentially favorable mineralogy (up to 25% combined concentration of Ca, Fe2+, and Mg cations) for storage of CO2. However, more information about the interaction of CO2 with aquifers and the host rock is needed. Core samples from the CRBG, as well as samples of olivine, serpentine, and sandstone, were reacted in an autoclave for up to 2000 hours at elevated temperatures and pressures. Changes in core porosity, secondary mineralizations, and both solution and solid chemistry were measured.

Carbon Dioxide Sequestration by Direct Mineral Carbonation with Carbonic Acid

Carbon Dioxide Sequestration by Direct Mineral Carbonation with Carbonic Acid PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

View

Book Description
The Albany Research Center (ARC) of the U.S. Dept. of Energy (DOE) has been conducting a series of mineral carbonation tests at its Albany, Oregon, facility over the past 2 years as part of a Mineral Carbonation Study Program within the DOE. Other participants in this Program include the Los Alamos National Laboratory, Arizona State University, Science Applications International Corporation, and the DOE National Energy Technology Laboratory. The ARC tests have focused on ex-situ mineral carbonation in an aqueous system. The process developed at ARC utilizes a slurry of water mixed with a magnesium silicate mineral, olivine [forsterite end member (Mg2SiO4)], or serpentine [Mg3Si2O5(OH)4]. This slurry is reacted with supercritical carbon dioxide (CO2) to produce magnesite (MgCO3). The CO2 is dissolved in water to form carbonic acid (H2CO3), which dissociates to H+ and HCO3 -. The H+ reacts with the mineral, liberating Mg2+ cations which react with the bicarbonate to form the solid carbonate. The process is designed to simulate the natural serpentinization reaction of ultramafic minerals, and for this reason, these results may also be applicable to in-situ geological sequestration regimes. Results of the baseline tests, conducted on ground products of the natural minerals, have been encouraging. Tests conducted at ambient temperature (22 C) and subcritical CO2 pressures (below 73 atm) resulted in very slow conversion to the carbonate. However, when elevated temperatures and pressures are utilized, coupled with continuous stirring of the slurry and gas dispersion within the water column, significant reaction occurs within much shorter reaction times. Extent of reaction, as measured by the stoichiometric conversion of the silicate mineral (olivine) to the carbonate, is roughly 90% within 24 hours, using distilled water, and a reaction temperature of 185?C and a partial pressure of CO2 (PCO2) of 115 atm. Recent tests using a bicarbonate solution, under identical reaction conditions, have achieved roughly 83% conversion of heat treated serpentine and 84% conversion of olivine to the carbonate in 6 hours. The results from the current studies suggest that reaction kinetics can be improved by pretreatment of the mineral, catalysis of the reaction, or some combination of the two. Future tests are intended to examine a broader pressure/temperature regime, various pretreatment options, as well as other mineral groups.

A Method for Permanent CO2 Mineral Carbonation

A Method for Permanent CO2 Mineral Carbonation PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

View

Book Description
The Albany Research Center (ARC) of the U.S. Department of Energy (DOE) has been conducting research to investigate the feasibility of mineral carbonation as a method for carbon dioxide (CO2) sequestration. The research is part of a Mineral Carbonation Study Program within the Office of Fossil Energy in DOE. Other participants in this Program include DOE?s Los Alamos National Laboratory and National Energy Technology Laboratory, Arizona State University, and Science Applications International Corporation. The research has focused on ex-situ mineral carbonation in an aqueous system. The process developed at ARC reacts a slurry of magnesium silicate mineral with supercritical CO2 to produce a solid magnesium carbonate product. To date, olivine and serpentine have been used as the mineral reactant, but other magnesium silicates could be used as well. The process is designed to simulate the natural serpentinization reaction of ultramafic minerals, and consequently, these results may also be applicable to strategies for in-situ geological sequestration. Baseline tests were begun in distilled water on ground products of foundry-grade olivine. Tests conducted at 150 C and subcritical CO2 pressures (50 atm) resulted in very slow conversion to carbonate. Increasing the partial pressure of CO2 to supercritical (>73 atm) conditions, coupled with agitation of the slurry and gas dispersion within the water column, resulted in significant improvement in the extent of reaction in much shorter reaction times. A change from distilled water to a bicarbonate/salt solution further improved the rate and extent of reaction. When serpentine, a hydrated mineral, was used instead of olivine, extent of reaction was poor until heat treatment was included prior to the carbonation reaction. Removal of the chemically bound water resulted in conversion to carbonate similar to those obtained with olivine. Recent results have shown that conversions of nearly 80 pct are achievable after 30 minutes at test conditions of 155 C and 185 atm CO2 in a bicarbonate/salt solution. The results from the current studies suggest that reaction kinetics can be further improved. Future tests will examine additional pressure/temperature regimes, various pretreatment options, and solution modifications.

Carbon Dioxide Sequestration by Direct Aqueous Mineral Carbonation

Carbon Dioxide Sequestration by Direct Aqueous Mineral Carbonation PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

View

Book Description
Carbon dioxide sequestration by an ex-situ, direct aqueous mineral carbonation process has been investigated over the past two years. This process was conceived to minimize the steps in the conversion of gaseous CO2 to a stable solid. This meant combining two separate reactions, mineral dissolution and carbonate precipitation, into a single unit operation. It was recognized that the conditions favorable for one of these reactions could be detrimental to the other. However, the benefits for a combined aqueous process, in process efficiency and ultimately economics, justified the investigation. The process utilizes a slurry of water, dissolved CO2, and a magnesium silicate mineral, such as olivine [forsterite end member (Mg2SiO4)], or serpentine [Mg3Si2O5(OH)4]. These minerals were selected as the reactants of choice for two reasons: (1) significant abundance in nature; and (2) high molar ratio of the alkaline earth oxides (CaO, MgO) within the minerals. Because it is the alkaline earth oxide that combines with CO2 to form the solid carbonate, those minerals with the highest ratio of these oxides are most favored. Optimum results have been achieved using heat pretreated serpentine feed material, sodium bicarbonate and sodium chloride additions to the solution, and high partial pressure of CO2 (PCO2). Specific conditions include: 155?C; PCO2=185 atm; 15% solids. Under these conditions, 78% conversion of the silicate to the carbonate was achieved in 30 minutes. Future studies are intended to investigate various mineral pretreatment options, the carbonation solution characteristics, alternative reactants, scale-up to a continuous process, geochemical modeling, and process economics.

Carbon Dioxide Sequestration by Mineral Carbonation of Iron-bearing Minerals

Carbon Dioxide Sequestration by Mineral Carbonation of Iron-bearing Minerals PDF Author: Kristin D. Lammers
Publisher:
ISBN:
Category :
Languages : en
Pages : 230

View

Book Description
Carbon dioxide (CO2) is formed when fossil fuels such as oil, gas and coal are burned in power producing plants. CO2 is naturally found in the atmosphere as part of the carbon cycle, however it becomes a primary greenhouse gas when human activities disturb this natural balanced cycle by increasing levels in the atmosphere. In light of this fact, greenhouse gas mitigation strategies have garnered a lot of attention. Carbon capture, utilization and sequestration (CCUS) has emerged as a possible strategy to limit CO2 emissions into the atmosphere. The technology involves capturing CO2 at the point sources, using it for other markets or transporting to geological formations for safe storage. This thesis aims to understand and probe the chemistry of the reactions between CO2 and iron-bearing sediments to ensure secure storage for millennia. The dissertation work presented here focused on trapping CO2 as a carbonate mineral as a permanent and secure method of CO2 storage. The research also explored the use of iron-bearing minerals found in the geological subsurface as candidates for trapping CO2 and sulfide gas mixtures as siderite (FeCO3) and iron sulfides. Carbon dioxide sequestration via the use of sulfide reductants of the iron oxyhydroxide polymorphs lepidocrocite, goethite and akaganeite with supercritical CO2 (scCO2) was investigated using in situ attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The exposure of the different iron oxyhydroxides to aqueous sulfide in contact with scCO2 at ~70-100 ̊C resulted in the partial transformation of the minerals to siderite (FeCO3). The order of mineral reactivity with regard to siderite formation in the scCO2/sulfide environment was goethite

Carbon Dioxide Sequestration in Cementitious Construction Materials

Carbon Dioxide Sequestration in Cementitious Construction Materials PDF Author: Fernando Pacheco-Torgal
Publisher: Woodhead Publishing
ISBN: 0081024479
Category : Technology & Engineering
Languages : en
Pages : 474

View

Book Description
Carbon Dioxide Sequestration in Cementitious Construction Materials provides an updated, state-of-the-art review on the development of cementitious construction materials based on carbon dioxide storage, which will have a major eco-efficient and economic benefit for the construction industry. Key chapters include methods for the assessment of carbon dioxide absorbed by cementitious materials, air and water-based carbon dioxide storage, carbon dioxide storage modeling, carbonation mechanisms, carbon dioxide storage on recycled aggregates, calcium, sodium and magnesium- based binders, properties and the durability of carbon dioxide based concrete. Promotes the importance of CO2 storage in carbonation of these materials, especially reincorporation of CO2 during fabrication Discusses a wide range of cementitious materials with CO2 storage capabilities Features redesign of cementation mechanisms to utilize CO2 during fabrication

Factors Affecting Ex-situ Aqueous Mineral Carbonation Using Calcium and Magnesium Silicate Minerals

Factors Affecting Ex-situ Aqueous Mineral Carbonation Using Calcium and Magnesium Silicate Minerals PDF Author: William K. O'Connor
Publisher:
ISBN:
Category :
Languages : en
Pages :

View

Book Description
Carbonation of magnesium- and calcium-silicate minerals to form their respective carbonates is one method to sequester carbon dioxide. Process development studies have identified reactor design as a key component affecting both the capital and operating costs of ex-situ mineral sequestration. Results from mineral carbonation studies conducted in a batch autoclave were utilized to design and construct a unique continuous pipe reactor with 100% recycle (flow-loop reactor). Results from the flow-loop reactor are consistent with batch autoclave tests, and are being used to derive engineering data necessary to design a bench-scale continuous pipeline reactor.