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(PDF) Use of waste calcium carbonate in sustainable cement
This con tribution illustrates the use of waste calcium carbonate, obtained from marble slurry (waste marble, WM), in sustainable cement materials alternative to
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Calcium Carbonate Cement: A Carbon Capture,
A novel calcium carbonate cement system that mimics the naturally occurring mineralization process of carbon dioxide to biogenic or geologic calcium carbonate deposits was developed utilizing carbon dioxide-containing flue gas and high-calcium industrial solid waste as raw materials. The calcium carbonate cement reaction is based on the
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Calcium carbonate synthesis from waste concrete for
Feb 05, 2021The Ca in the waste cement reacted with HCl to dissolve Ca in solution, and the amount of material and HCl solution could be determined according to the molar ratio of Ca and HCl. Here, since 2 M of HCl reacts with 1 M of Ca, twice as much HCl should be added. The extraction efficiencies with various HCl concentrations were investigated ( Fig. 3 ).
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The role of calcium carbonate in cement hydration
Apr 01, 2007Limestone, mainly consisting of calcite, is a permitted additive to Portland cements often up to a 5 wt.% limit. It is shown by experiment and calculation that much, if not all, of this calcite is reactive and affects the distribution of lime, alumina and sulfate and thereby alters the mineralogy of hydrated cement pastes.
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Production of carbon negative precipitated calcium
Oct 05, 2016The production of cement accounts for 9.5 % of global CO 2 emissions, however up to 50 % of the manufacturing emissions can be mitigated at the end of the materials service life through mineral carbonation. The objective here is to sequester CO 2 through the production of PCC via the recovery and carbonation of calcium from waste cement.
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Green new concrete recycles building waste and captured
Oct 11, 2021It may be easier on the environment, but the calcium carbonate concrete isn’t quite as strong as the usual stuff yet. The average compressive strength of the blocks was 8.6 MPa, which is far lower...
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Recovery and carbonation of 100% of calcium in waste
Feb 10, 2018we propose an indirect, aqueous process consisting of six steps: (i) recovery of waste cement (primarily calcium silicate hydrate) from waste concrete, (ii) leaching of calcium from waste cement using hydrochloric acid, (iii) purification of the leachate through alkalinity addition, (iv) precipitation of calcium carbonate via aqueous reaction
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Carbonation of cement paste: Understanding, challenges
Aug 01, 2016studies by nmr spectroscopy indicate that decomposition of c-s-h caused by carbonation involves two steps [36]: (1) a gradual decalcification of the c-s-h, where calcium is removed from the interlayer and defect sites in the silicate chains until ca/si = 0.67 is reached, ideally corresponding to infinite silicate chains; (2) calcium from the
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Calcium carbonate Wikipedia
Calcium carbonate is a chemical compound with the formula Ca CO 3. It is a common substance found in rocks as the minerals calcite and aragonite (most notably as limestone, which is a type of sedimentary rock consisting mainly of calcite) and is the main component of eggshells, gastropod shells, shellfish skeletons and pearls.
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Calcium carbonate synthesis from waste concrete for carbon
Feb 05, 2021This research article explains the synthesis and scale-up of calcium carbonate (CaCO<sub>3</sub>) from waste concrete as calcium-rich material by an inorganic carbonation process. The operating parameters include S/L ratio, HCl concentration, contact time, and extraction pH were investigated. The ca
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Calcium Carbonate Cement: A Carbon Capture, Utilization,
power plants, chemical plants, and cement kilns. Calcium and alkalinity can come from industrial waste streams that contain both calcium and alkalinity in the form of calcium oxide (CaO), calcium hydroxide (Ca(OH)2), and calcium silicates. Examples of calcium and alkalinity-rich industrial waste streams include: carbide lime sludge, an impure
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Development of a process for producing high‐purity calcium carbonate
Jun 14, 2005A new type of process for producing high-purity calcium carbonate from waste cement powder was developed. The process consists of two main reactions; extraction of calcium in the form of calcium ions from waste cement powder in a water slurry by pressurized CO 2 (typically at several MPa), and precipitation of calcium carbonate (CaCO 3) from the
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Cement from Waste Materials
On the other hand, a wet process cement plant could handle them without much trouble. In the Leblanc Process for making sodium carbonate, calcium sulfide is produced as waste: 2NaCl + H 2 SO 4 → Na 2 SO 4 + 2HCl. Na 2 SO 4 + CaCO 3 + 2C → Na 2 CO 3 + CaS + 2CO 2.
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Materials Free Full-Text Calcium Carbonate Cement: A Carbon
May 21, 2021A novel calcium carbonate cement system that mimics the naturally occurring mineralization process of carbon dioxide to biogenic or geologic calcium carbonate deposits was developed utilizing carbon dioxide-containing flue gas and high-calcium industrial solid waste as raw materials. The calcium carbonate cement reaction is based on the polymorphic
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Experimental and modeling study of calcium carbonate
Jul 18, 2018@article{osti_1467386, title = {Experimental and modeling study of calcium carbonate precipitation and its effects on the degradation of oil well cement during carbonated brine exposure}, author = {Matteo, Edward N. and Huet, Bruno and Jové-Colón, Carlos F. and Scherer, George W.}, abstractNote = {Decalcification of cement in solutions of carbonated
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The Potential to Replace Cement with Nano-Calcium Carbonate and Natural
Mar 09, 2021The effectiveness of mine backfilling depends on the properties of its constituents. The high cost of cement, which is commonly used as a binder in mine backfill, has led researchers to seek alternatives to partially replace it with other binders. This study investigated the potential to use nano-calcium carbonate (NCC) and natural pozzolans (zeolite and
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Microstructure-property relationships in cement mortar with
2 天前Investigating the potential for microbially induced carbonate precipitation to treat mine waste. J Hazard Mater, 424 (2022 M. Cao, X. Ming, H. Yin, L. Li. Influence of high temperature on strength, ultrasonic velocity and mass loss of calcium carbonate whisker reinforced cement paste. Compos B Eng, 163 (2019), pp. 438-446. Article Download
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Scientists create renewable biocement made entirely from waste
May 13, 2022The NTU scientists have now managed to use two common waste materials, industrial carbide sludge and urea—from the urine of mammals—to create biocement. They developed a process in which the reaction of urea with calcium ions in industrial carbide sludge forms a hard solid, or precipitate. When this reaction takes place in soil, the
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Biomineralization of cyanobacteria Synechocystis pevalekii
Microbially induced calcium carbonate precipitation (MICCP) is considered a novel eco-friendly technique to enhance the structural properties of cementitious-based material. Maxim
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Biomineralization of cyanobacteria Synechocystis pevalekii
May 19, 2022Microbially induced calcium carbonate precipitation (MICCP) is considered a novel eco-friendly technique to enhance the structural properties of cementitious-based material. Maximum studies have emphasized using ureolytic bacteria to improve the durability properties of building structures. In this study, the role of photoautotrophic bacteria Synechocystis pevalekii
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Development of a process for producing high‐purity calcium carbonate
Katsuyama et al. [36] developed a new process to extract highpurity calcium carbonate from waste cement. In this process the calcium ions are extracted using desulphurized CO 2
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CO2 Mineralization Methods in Cement and Concrete Industry
Production of Portland clinker is inherently associated with CO2 emissions originating from limestone decomposition, the irreplaceable large-scale source of calcium oxide needed. Besides carbon capture and storage, CO2 mineralization is the only lever left to reduce these process emissions. CO2 mineralization is a reversal reaction to clinker production—CO2 is
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Calcium carbonate Essential Chemical Industry
The calcium sulfite reacts with the air to form calcium sulfate (gypsum), used to make, for example, plaster board and cement. Very fine and pure calcium carbonate is used as filler in and . A filler is a substance that gives bulk but does not alter the properties of the substance to which it is added and is also inert. Calcium
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Development of a process for producing high‐purity calcium carbonate
Katsuyama et al. [36] developed a new process to extract highpurity calcium carbonate from waste cement. In this process the calcium ions are extracted using desulphurized CO 2
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Development of a process for producing high‐purity calcium carbonate
Jun 14, 2005A new type of process for producing high‐purity calcium carbonate from waste cement powder was developed. The process consists of two main reactions; extraction of calcium in the form of calcium ions from waste cement powder in a water slurry by pressurized CO 2 (typically at several MPa), and precipitation of calcium carbonate (CaCO 3) from the
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Calcium Carbonate Cement: A Carbon Capture, Utilization
May 21, 2021A novel calcium carbonate cement system that mimics the naturally occurring mineralization process of carbon dioxide to biogenic or geologic calcium carbonate deposits was developed utilizing carbon dioxide-containing flue gas and high-calcium industrial solid waste as raw materials. The calcium carbonate cement reaction is based on the
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Materials Free Full-Text Calcium Carbonate Cement: A Carbon
May 21, 2021A novel calcium carbonate cement system that mimics the naturally occurring mineralization process of carbon dioxide to biogenic or geologic calcium carbonate deposits was developed utilizing carbon dioxide-containing flue gas and high-calcium industrial solid waste as raw materials. The calcium carbonate cement reaction is based on the polymorphic
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Concrete needs to lose its colossal carbon footprint
Sep 28, 2021The injected CO 2 reacts with calcium ions in the cement, producing more calcium carbonate, the European Union’s Waste Framework Directive requires 70% of construction waste to be reused
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Calcium carbonate Essential Chemical Industry
The calcium sulfite reacts with the air to form calcium sulfate (gypsum), used to make, for example, plaster board and cement. Very fine and pure calcium carbonate is used as filler in and . A filler is a substance that gives bulk but does not alter the properties of the substance to which it is added and is also inert. Calcium
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Recycled concrete and captured CO2 make new building material
Oct 08, 2021Now, the University of Tokyo researchers have demonstrated a method for combining waste concrete and captured CO2 to create a usable form of concrete called calcium carbonate concrete. Inspired by the way some aquatic organisms harden into fossils over time, Professor Ippei Maruyama wondered if the same process for forming hard calcium
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EP2512991A1 Production of calcium carbonate from waste
A method of producing calcium carbonate from a waste sludge containing calcium carbonate and at least one silicate mineral. The method comprises the steps of: (i) incinerating the sludge to an ash in which at least 60 % of the calcium carbonate present in the sludge is converted to free calcium oxide which is unreacted with the silicate mineral(s), (ii) optionally slaking the ash to
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Microstructure-property relationships in cement mortar with
2 天前Investigating the potential for microbially induced carbonate precipitation to treat mine waste. J Hazard Mater, 424 (2022 M. Cao, X. Ming, H. Yin, L. Li. Influence of high temperature on strength, ultrasonic velocity and mass loss of calcium carbonate whisker reinforced cement paste. Compos B Eng, 163 (2019), pp. 438-446. Article Download
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Scientists create renewable biocement made entirely from waste
May 13, 2022The NTU scientists have now managed to use two common waste materials, industrial carbide sludge and urea—from the urine of mammals—to create biocement. They developed a process in which the reaction of urea with calcium ions in industrial carbide sludge forms a hard solid, or precipitate. When this reaction takes place in soil, the
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Calcium carbonate Wikipedia
Calcium carbonate is a chemical compound with the formula Ca CO 3.It is a common substance found in rocks as the minerals calcite and aragonite (most notably as limestone, which is a type of sedimentary rock consisting mainly of calcite) and is the main component of eggshells, gastropod shells, shellfish skeletons and pearls.Calcium carbonate is the active ingredient in agricultural
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Biomineralization of cyanobacteria Synechocystis pevalekii
Microbially induced calcium carbonate precipitation (MICCP) is considered a novel eco-friendly technique to enhance the structural properties of cementitious-based material. Maxim
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Mechanical and Durability Properties of Portland Limestone Cement
Feb 14, 2021This stone evaluates the use of nano calcium carbonate (CaCO 3) as partial replacements (replacement rates of 1%, Additionally, nano CaCO 3 can be produced within the cement plant utilizing the waste CO 2 using an integrated approach for green and economical cement production
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Biomineralization of cyanobacteria Synechocystis pevalekii
May 19, 2022Microbially induced calcium carbonate precipitation (MICCP) is considered a novel eco-friendly technique to enhance the structural properties of cementitious-based material. Maximum studies have emphasized using ureolytic bacteria to improve the durability properties of building structures. In this study, the role of photoautotrophic bacteria Synechocystis pevalekii
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