Carbon Dioxide Uptake During Concrete Life Cycle

Carbon Dioxide Uptake During Concrete Life Cycle PDF Author: Björn Lagerblad
Publisher:
ISBN: 9789197607001
Category : Atmospheric carbon dioxide
Languages : en
Pages : 47

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Book Description
Carbonation results when carbonate ions from dissolved carbon dioxide react with the Ca ions of the cement paste and precipitate calcium carbonate. By time all Ca-bearing cement hydrates will decompose and form calcite. The end product will apart from calcite be silica gels, metal hydroxides and clays. Carbon dioxide and water can be found in almost every environment and thus all concretes will be subjected to carbonation. The cement paste will in the course of time go back to the basic components in cement production. Therefore, the question is not if concrete and other cementitious products will carbonate, but how fast they will carbonate. In geological terns the cement paste turns into marly limestone and the concrete into marly agglomerate. Old Roman concrete structures are basically such a rock. Carbonation is a process from the surface, i.e. the amount of carbonated material is related to exposure time and surface. Surfaces in direct contact with carbon dioxide and water will carbonate rapidly but a shell of already carbonated concrete will slow down the carbonation of the interior. Thus to be able to calculate the CO2-uptake we must know the transport mechanism of carbon dioxide and carbonate ions through the already altered product. The process of passing a shell of already carbonated concrete is complex. The speed of carbonation is apart from the amount of CO2 in the environment also governed by the size and geometry of the porosity, the degree of water saturation, the type of cement/binder, the temperature, etc. Even concrete submerged in water or buried in soil will carbonate but at a slow speed due to biological degradation and the slowness of exchange reactions between water and the gases in the atmosphere. To be able to calculate CO2 uptake one must consider the microclimate at individual concrete surfaces, concrete qualities and cement/binder types in a time frame. Thus approximations are needed. In the general case assuming a similar environment and concrete quality the carbonation rate slows down with the square root of time. By choosing the most common types of concrete structures, estimating the exposed surfaces in different environments and concrete qualities it is possible to get a good estimate of the rate of carbon dioxide uptake. As a consequence of the rapidly decreasing rate of carbonation one can assume that most of the carbonation of concrete structures takes place during the first 50 years and after demolition as this will increase the surfaces dramatically. One must, however, also consider that the types of cement and quality of the concrete have changed and will change over time. Thus there will be a difference between how much is taken up today and how much that will be taken up in 50 years from now. Concrete is a fairly modern material and most concrete structures still remain but we can expect the amount of demolished concrete to increase in the future. A guess is that a 100-year perspective most concrete structures that exist today will probably be demolished and most of the carbonate rock calcinated during cement production will be back as a carbonate rock. To be able to calculate the carbonation rate some simplifications are needed. In this report concrete strength is used as a substitute for porosity and from literature data constants for different environmental classes are selected. The influence of different cements and additions is handled by correction factors.

Carbon Dioxide Uptake During Concrete Life Cycle

Carbon Dioxide Uptake During Concrete Life Cycle PDF Author: Björn Lagerblad
Publisher:
ISBN: 9789197607001
Category : Atmospheric carbon dioxide
Languages : en
Pages : 47

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Book Description
Carbonation results when carbonate ions from dissolved carbon dioxide react with the Ca ions of the cement paste and precipitate calcium carbonate. By time all Ca-bearing cement hydrates will decompose and form calcite. The end product will apart from calcite be silica gels, metal hydroxides and clays. Carbon dioxide and water can be found in almost every environment and thus all concretes will be subjected to carbonation. The cement paste will in the course of time go back to the basic components in cement production. Therefore, the question is not if concrete and other cementitious products will carbonate, but how fast they will carbonate. In geological terns the cement paste turns into marly limestone and the concrete into marly agglomerate. Old Roman concrete structures are basically such a rock. Carbonation is a process from the surface, i.e. the amount of carbonated material is related to exposure time and surface. Surfaces in direct contact with carbon dioxide and water will carbonate rapidly but a shell of already carbonated concrete will slow down the carbonation of the interior. Thus to be able to calculate the CO2-uptake we must know the transport mechanism of carbon dioxide and carbonate ions through the already altered product. The process of passing a shell of already carbonated concrete is complex. The speed of carbonation is apart from the amount of CO2 in the environment also governed by the size and geometry of the porosity, the degree of water saturation, the type of cement/binder, the temperature, etc. Even concrete submerged in water or buried in soil will carbonate but at a slow speed due to biological degradation and the slowness of exchange reactions between water and the gases in the atmosphere. To be able to calculate CO2 uptake one must consider the microclimate at individual concrete surfaces, concrete qualities and cement/binder types in a time frame. Thus approximations are needed. In the general case assuming a similar environment and concrete quality the carbonation rate slows down with the square root of time. By choosing the most common types of concrete structures, estimating the exposed surfaces in different environments and concrete qualities it is possible to get a good estimate of the rate of carbon dioxide uptake. As a consequence of the rapidly decreasing rate of carbonation one can assume that most of the carbonation of concrete structures takes place during the first 50 years and after demolition as this will increase the surfaces dramatically. One must, however, also consider that the types of cement and quality of the concrete have changed and will change over time. Thus there will be a difference between how much is taken up today and how much that will be taken up in 50 years from now. Concrete is a fairly modern material and most concrete structures still remain but we can expect the amount of demolished concrete to increase in the future. A guess is that a 100-year perspective most concrete structures that exist today will probably be demolished and most of the carbonate rock calcinated during cement production will be back as a carbonate rock. To be able to calculate the carbonation rate some simplifications are needed. In this report concrete strength is used as a substitute for porosity and from literature data constants for different environmental classes are selected. The influence of different cements and additions is handled by correction factors.

Cement Chemistry

Cement Chemistry PDF Author: H F W Taylor
Publisher: Thomas Telford
ISBN: 9780727725929
Category : Science
Languages : en
Pages : 488

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Book Description
A revised and updated text on cement chemistry. This edition forms a comprehensive and in-depth reference work that explains in detail all aspects of cement chemistry.

Cementitious Materials

Cementitious Materials PDF Author: Herbert Pöllmann
Publisher: Walter de Gruyter GmbH & Co KG
ISBN: 3110473720
Category : Science
Languages : en
Pages : 518

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Book Description
Aside from water the materials which are used by mankind in highest quantities arecementitious materials and concrete. This book shows how the quality of the technical product depends on mineral phases and their reactions during the hydration and strengthening process. Additives and admixtures infl uence the course of hydration and the properties. Options of reducing the CO2-production in cementitious materials are presented and numerous examples of unhydrous and hydrous phases and their formation conditions are discussed. This editorial work consists of four parts including cement composition and hydration, Special cement and binder mineral phases, Cementitious and binder materials, and Measurement and properties. Every part contains different contributions and covers a broad range within the area. Contents Part I: Cement composition and hydration Diffraction and crystallography applied to anhydrous cements Diffraction and crystallography applied to hydrating cements Synthesis of highly reactive pure cement phases Thermodynamic modelling of cement hydration: Portland cements – blended cements – calcium sulfoaluminate cements Part II: Special cement and binder mineral phases Role of hydrotalcite-type layered double hydroxides in delayed pozzolanic reactions and their bearing on mortar dating Setting control of CAC by substituted acetic acids and crystal structures of their calcium salts Crystallography and crystal chemistry of AFm phases related to cement chemistry Part III: Cementitious and binder materials Chemistry, design and application of hybrid alkali activated binders Binding materials based on calcium sulphates Magnesia building material (Sorel cement) – from basics to application New CO2-reduced cementitious systems Composition and properties of ternary binders Part IV: Measurement and properties Characterization of microstructural properties of Portland cements by analytical scanning electron microscopy Correlating XRD data with technological properties No cement production without refractories

A Review of Carbonation in Reinforced Concrete

A Review of Carbonation in Reinforced Concrete PDF Author: L. J. Parrott
Publisher:
ISBN: 9780721013657
Category : Reinforced concrete
Languages : en
Pages : 43

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Book Description
This book reviews the damage that can arise when concrete cover becomes carbonated and the underlying reinforcing steel corrodes. It includes a description of what is known of carbonation from laboratory tests, a compilation and assessment of field data, reports of carbonation-induced damage in reinforced concrete and conclusions regarding present understanding and future research needs.

Gaseous Carbon Waste Streams Utilization

Gaseous Carbon Waste Streams Utilization PDF Author: National Academies of Sciences, Engineering, and Medicine
Publisher: National Academies Press
ISBN: 0309483360
Category : Science
Languages : en
Pages : 257

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Book Description
In the quest to mitigate the buildup of greenhouse gases in Earth's atmosphere, researchers and policymakers have increasingly turned their attention to techniques for capturing greenhouse gases such as carbon dioxide and methane, either from the locations where they are emitted or directly from the atmosphere. Once captured, these gases can be stored or put to use. While both carbon storage and carbon utilization have costs, utilization offers the opportunity to recover some of the cost and even generate economic value. While current carbon utilization projects operate at a relatively small scale, some estimates suggest the market for waste carbon-derived products could grow to hundreds of billions of dollars within a few decades, utilizing several thousand teragrams of waste carbon gases per year. Gaseous Carbon Waste Streams Utilization: Status and Research Needs assesses research and development needs relevant to understanding and improving the commercial viability of waste carbon utilization technologies and defines a research agenda to address key challenges. The report is intended to help inform decision making surrounding the development and deployment of waste carbon utilization technologies under a variety of circumstances, whether motivated by a goal to improve processes for making carbon-based products, to generate revenue, or to achieve environmental goals.

Handbook of Recycled Concrete and Demolition Waste

Handbook of Recycled Concrete and Demolition Waste PDF Author: F. Pacheco-Torgal
Publisher: Elsevier
ISBN: 0857096907
Category : Technology & Engineering
Languages : en
Pages : 671

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Book Description
The civil engineering sector accounts for a significant percentage of global material and energy consumption and is a major contributor of waste material. The ability to recycle and reuse concrete and demolition waste is critical to reducing environmental impacts in meeting national, regional and global environmental targets. Handbook of recycled concrete and demolition waste summarises key recent research in achieving these goals.Part one considers techniques for managing construction and demolition waste, including waste management plans, ways of estimating levels of waste, the types and optimal location of waste recycling plants and the economics of managing construction and demolition waste. Part two reviews key steps in handling construction and demolition waste. It begins with a comparison between conventional demolition and construction techniques before going on to discuss the preparation, refinement and quality control of concrete aggregates produced from waste. It concludes by assessing the mechanical properties, strength and durability of concrete made using recycled aggregates. Part three includes examples of the use of recycled aggregates in applications such as roads, pavements, high-performance concrete and alkali-activated or geopolymer cements. Finally, the book discusses environmental and safety issues such as the removal of gypsum, asbestos and alkali-silica reaction (ASR) concrete, as well as life-cycle analysis of concrete with recycled aggregates.Handbook of recycled concrete and demolition waste is a standard reference for all those involved in the civil engineering sector, as well as academic researchers in the field. - Summarises key recent research in recycling and reusing concrete and demolition waste to reduce environmental impacts and meet national, regional and global environmental targets - Considers techniques for managing construction and demolition waste, including waste management plans, ways of estimating levels of waste, the types and optimal location of waste recycling plants - Reviews key steps in handling construction and demolition waste

Life Cycle Assessment on Green Building Implementation

Life Cycle Assessment on Green Building Implementation PDF Author: Vivian W. Y. Tam
Publisher: MDPI
ISBN: 3038422568
Category : Architecture
Languages : en
Pages : 329

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Book Description
This book is a printed edition of the Special Issue "Life Cycle Assessment on Green Building Implementation" that was published in Sustainability

Climate Intervention

Climate Intervention PDF Author: National Research Council
Publisher: National Academies Press
ISBN: 0309305322
Category : Science
Languages : en
Pages : 235

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Book Description
The signals are everywhere that our planet is experiencing significant climate change. It is clear that we need to reduce the emissions of carbon dioxide and other greenhouse gases from our atmosphere if we want to avoid greatly increased risk of damage from climate change. Aggressively pursuing a program of emissions abatement or mitigation will show results over a timescale of many decades. How do we actively remove carbon dioxide from the atmosphere to make a bigger difference more quickly? As one of a two-book report, this volume of Climate Intervention discusses CDR, the carbon dioxide removal of greenhouse gas emissions from the atmosphere and sequestration of it in perpetuity. Climate Intervention: Carbon Dioxide Removal and Reliable Sequestration introduces possible CDR approaches and then discusses them in depth. Land management practices, such as low-till agriculture, reforestation and afforestation, ocean iron fertilization, and land-and-ocean-based accelerated weathering, could amplify the rates of processes that are already occurring as part of the natural carbon cycle. Other CDR approaches, such as bioenergy with carbon capture and sequestration, direct air capture and sequestration, and traditional carbon capture and sequestration, seek to capture CO2 from the atmosphere and dispose of it by pumping it underground at high pressure. This book looks at the pros and cons of these options and estimates possible rates of removal and total amounts that might be removed via these methods. With whatever portfolio of technologies the transition is achieved, eliminating the carbon dioxide emissions from the global energy and transportation systems will pose an enormous technical, economic, and social challenge that will likely take decades of concerted effort to achieve. Climate Intervention: Carbon Dioxide Removal and Reliable Sequestration will help to better understand the potential cost and performance of CDR strategies to inform debate and decision making as we work to stabilize and reduce atmospheric concentrations of carbon dioxide.

Carbon Dioxide Sequestration in Cementitious Construction Materials

Carbon Dioxide Sequestration in Cementitious Construction Materials PDF Author: F. Pacheco-Torgal
Publisher: Elsevier
ISBN: 0443135789
Category : Technology & Engineering
Languages : en
Pages : 428

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Book Description
Carbon Dioxide Sequestration in Cementitious Construction Materials – Second Edition follows on the success of the previous edition and provides an up-to-date review on recent research developments on cementitious construction materials based on carbon dioxide storage. Along with the addition of an entire new section on bio- sequestration. Brand new chapters are included on carbonation methods such as carbon sequestration of cement pastes during pressurized CO2 curing; carbon dioxide sequestration of low-calcium fly ash via direct aqueous carbonation; increasing the efficiency of carbon dioxide sequestration through high temperature carbonation; and carbon sequestration in engineered cementitious composites. There are also several new case studies on sequestration of industrial wastes, which include carbon dioxide sequestration by direct mineralization of fly ash; the effect of direct carbonation routes of basic oxygen furnace slag on strength and hydration of blended cement paste; carbon sequestration of mine waste and utilization as a supplementary cementitious material and carbon dioxide sequestration on masonry blocks based on industrial wastes. This updated edition will be a valuable reference resource for academic researchers, materials scientists and civil engineers, and other construction professionals looking for viable routes for carbon sequestration in building materials. - Promotes the importance of CO2 storage in carbonation of construction 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 - Includes a new section on bio-sequestration

Carbon Dioxide Utilisation

Carbon Dioxide Utilisation PDF Author: Peter Styring
Publisher: Elsevier
ISBN: 0444627480
Category : Technology & Engineering
Languages : en
Pages : 337

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Book Description
Carbon Dioxide Utilisation: Closing the Carbon Cycle explores areas of application such as conversion to fuels, mineralization, conversion to polymers, and artificial photosynthesis as well as assesses the potential industrial suitability of the various processes. After an introduction to the thermodynamics, basic reactions, and physical chemistry of carbon dioxide, the book proceeds to examine current commercial and industrial processes, and the potential for carbon dioxide as a green and sustainable resource. While carbon dioxide is generally portrayed as a "bad" gas, a waste product, and a major contributor to global warming, a new branch of science is developing to convert this "bad" gas into useful products. This book explores the science behind converting CO2 into fuels for our cars and planes, and for use in plastics and foams for our homes and cars, pharmaceuticals, building materials, and many more useful products. Carbon dioxide utilization is a rapidly expanding area of research that holds a potential key to sustainable, petrochemical-free chemical production and energy integration. - Accessible and balanced between chemistry, engineering, and industrial applications - Informed by blue-sky thinking and realistic possibilities for future technology and applications - Encompasses supply chain sustainability and economics, processes, and energy integration