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P E Tsakiridis - One of the best experts on this subject based on the ideXlab platform.
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silico aluminous bottom ash valorisation in Cement Clinker production synthesis characterization and hydration properties
Construction and Building Materials, 2016Co-Authors: P E Tsakiridis, Michail Samouhos, A Peppas, N S Katsiotis, D Velissariou, Marios S Katsiotis, M BeaziAbstract:Abstract The utilization of Silico-Aluminous Bottom Ash (SABA), derived from bituminous coal combustion in power plants, was investigated as a raw material in the kiln feed for the production of ordinary Portland Cement Clinker. Three different raw meals were studied, containing natural raw materials with 0, 3 and 6 wt% of SABA. The raw mixes reactivity was assessed in terms of unreacted lime content, following sintering at 1200, 1350, 1400 and 1450 °C. Clinkers produced at 1450 °C, were characterized through means of chemical analysis, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The characterized Clinkers were used to produce Cement specimens by co-grinding with suitable amount of gypsum. Accordingly, Cement quality was evaluated by determining setting times, standard consistency, expansibility and compressive strength at 2, 7 and 28 days. XRD and TG/DTG analysis were used for the hydration study evolution after 28 days of curing. SABA presents a promising alternative in waste valorisation practice, as it can readily be used in the raw kiln feed as a partial replaCement of ordinary raw materials.
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Black Dross Leached Residue: An Alternative Raw Material for Portland Cement Clinker
Waste and Biomass Valorization, 2014Co-Authors: P E Tsakiridis, P Oustadakis, S. Agatzini-leonardouAbstract:The possibility of adding an aluminium black dross leached residue (BDLR), mainly consisted of spinel (Al_2MgO_4) and corundum (Al_2O_3), in the raw meal for the production of Portland Cement Clinker was investigated. This leached residue was obtained during the hydrothermal treatment of an aluminium black dross, formed during aluminium scrap melting. The process consisted of crushing and grinding of the as received dross, sieving it to recover the Al metal value, water leaching at high temperature to dissolve the salts and, finally, aluminium recovery by alkaline pressure leaching. Three samples of raw meals were prepared, one with ordinary raw materials, as a reference sample ((PC)_Ref), and two others with different content (2 and 4 wt%) of BDLR ((PC)_BD-2% and (PC)_BD-42%). All raw meals were sintered at 1,450 ^◦C and the produced Clinkers were characterised by chemical analysis, X-ray diffraction (XRD), thermogravimetric/differential thermal analysis (TG/DTA) as well as scanning electron microscopy. The produced Cements were tested by determining their grindability, setting time, compressive strength and expansibility. The hydration products were examined by XRD analysis at 2, 7 and 28 days. The results of the physico-mechanical tests showed that BDLR could be utilized as a raw material in the Cement Clinker production, presenting a promising alternative to disposal in landfills.
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utilization of steel slag for Portland Cement Clinker production
Journal of Hazardous Materials, 2008Co-Authors: P E Tsakiridis, G D Papadimitriou, Sotiris Tsivilis, Christopher KoroneosAbstract:Abstract The aim of the present research work is to investigate the possibility of adding steel slag, a by-product of the conversion of iron to steel process, in the raw meal for the production of Portland Cement Clinker. Two samples of raw meals were prepared, one with ordinary raw materials, as a reference sample ((PC) Ref ), and another with 10.5% steel slag ((PC) S/S ). Both raw meals were sintered at 1450 °C. The results of chemical and mineralogical analyses as well as the microscopic examination showed that the use of the steel slag did not affect the mineralogical characteristics of the so produced Portland Cement Clinker. Furthermore, both Clinkers were tested by determining the grindability, setting times, compressive strengths and soundness. The hydration products were examined by XRD analysis at 2, 7, 28 and 90 days. The results of the physico-mechanical tests showed that the addition of the steel slag did not negatively affect the quality of the produced Cement.
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examination of the jarosite alunite precipitate addition in the raw meal for the production of Portland Cement Clinker
Cement and Concrete Research, 2005Co-Authors: P E Tsakiridis, S Agatzinileonardou, P Oustadakis, M Katsioti, E MauridouAbstract:Abstract The aim of the present research work was to investigate the possibility of adding a jarosite–alunite chemical precipitate, a waste product of a new hydrometallurgical process developed to treat economically low grade nickel oxides ores, in the raw meal for the production of Portland Cement Clinker. For that reason, two samples of raw meals were prepared, one with ordinary raw materials, as a reference sample ((PC)Ref) and another with 1% jarosite–alunite precipitate ((PC)J/A). Both raw meals were sintered at 1450 °C. The results of chemical and mineralogical analyses as well as the microscopic examination showed that the use of the jarosite–alunite precipitate did not affect the mineralogical characteristics of the so produced Portland Cement Clinker. Furthermore, both Clinkers were tested by determining the grindability, setting time, compressive strength and expansibility. The hydration products were examined by XRD analysis at 2, 7, 28 and 90 days. The results of the physico-mechanical tests showed that the addition of jarosite–alunite precipitate did not negatively affect the quality of the produced Cement.
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red mud addition in the raw meal for the production of Portland Cement Clinker
Journal of Hazardous Materials, 2004Co-Authors: P E Tsakiridis, S Agatzinileonardou, P OustadakisAbstract:Abstract The aim of the present research work was to investigate the possibility of adding red mud, an alkaline leaching waste, which is obtained from bauxite during the Bayer process for alumina production, in the raw meal for the production of Portland Cement Clinker. For that reason, two samples of raw meals were prepared: one with ordinary raw materials, as a reference sample ((PC)Ref), and another with 3.5% red mud ((PC)R/M). The effect on the reactivity of the raw mix was evaluated on the basis of the unreacted lime content in samples sintered at 1350, 1400 and 1450 °C. Subsequently, the Clinkers were produced by sintering the two raw meals at 1450 °C. The results of chemical and mineralogical analyses as well as the microscopic examination showed that the use of the red mud did not affect the mineralogical characteristics of the so produced Portland Cement Clinker. Furthermore, both Clinkers were tested by determining the grindability, setting time, compressive strength and expansibility. The hydration products were examined by XRD analysis at 2, 7, 28 and 90 days. The results of the physico-mechanical tests showed that the addition of the red mud did not negatively affect the quality of the produced Cement.
Christopher Koroneos - One of the best experts on this subject based on the ideXlab platform.
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utilization of steel slag for Portland Cement Clinker production
Journal of Hazardous Materials, 2008Co-Authors: P E Tsakiridis, G D Papadimitriou, Sotiris Tsivilis, Christopher KoroneosAbstract:Abstract The aim of the present research work is to investigate the possibility of adding steel slag, a by-product of the conversion of iron to steel process, in the raw meal for the production of Portland Cement Clinker. Two samples of raw meals were prepared, one with ordinary raw materials, as a reference sample ((PC) Ref ), and another with 10.5% steel slag ((PC) S/S ). Both raw meals were sintered at 1450 °C. The results of chemical and mineralogical analyses as well as the microscopic examination showed that the use of the steel slag did not affect the mineralogical characteristics of the so produced Portland Cement Clinker. Furthermore, both Clinkers were tested by determining the grindability, setting times, compressive strengths and soundness. The hydration products were examined by XRD analysis at 2, 7, 28 and 90 days. The results of the physico-mechanical tests showed that the addition of the steel slag did not negatively affect the quality of the produced Cement.
Carl-alexander Graubner - One of the best experts on this subject based on the ideXlab platform.
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eco friendly concretes with reduced water and Cement content mix design principles and experimental tests
2017Co-Authors: Tilo Proske, Stefan Hainer, Moien Rezvani, Carl-alexander GraubnerAbstract:The major environmental impact of concrete is caused by CO 2 emissions during Cement production. Great potential for reducing the impact is seen especially for concretes with normal strength. The use of superplasticizers and highly reactive Cements as well as an optimization of particle-size distribution and reduction in water content allow a significant reduction in Portland Cement Clinker in the Cement and concrete. Essential is the addition of mineral fillers (e.g., limestone powder) to provide an optimal paste volume. In addition, the already practicable substitution of secondary raw materials like fly ash or furnace slag for Cement Clinker is an appropriate option that is, however, limited by the availability of these resources.
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chapter 4 eco friendly concretes with reduced water and Cement content mix design principles and experimental tests
Handbook of Low Carbon Concrete, 2017Co-Authors: Tilo Proske, Stefan Hainer, Moien Rezvani, Carl-alexander GraubnerAbstract:The major environmental impact of concrete is caused by CO2 emissions during Cement production. Great potential for reducing the impact is seen especially for concretes with normal strength. The use of superplasticizers and highly reactive Cements as well as an optimization of particle-size distribution and reduction in water content allow a significant reduction in Portland Cement Clinker in the Cement and concrete. Essential is the addition of mineral fillers (e.g., limestone powder) to provide an optimal paste volume. In addition, the already practicable substitution of secondary raw materials like fly ash or furnace slag for Cement Clinker is an appropriate option that is, however, limited by the availability of these resources. In several test series the fresh and hardened concrete properties of concretes with reduced water and Cement content were investigated, especially their workability, strength development, design-relevant mechanical properties, and durability aspects such as carbonation and resistance against sulfate attack. It was shown that concretes with Cement Clinker and slag contents as low as 150 kg/m³ were able to meet the usual requirements of workability, compressive strength (~40 N/mm²), and mechanical properties. The carbonation depth of concretes with 150–175 kg/m³ Clinker and slag was equal to or lower than the depth of conventional reference concretes for exterior structures. The ecological advantages were identified using environmental performance evaluation. A reduction of up to 35% in environmental impact was calculated compared with conventional concrete and of more than 60% with granulated blast furnace slag. Practical application was verified by means of full-scale tests in a precast and ready-mix concrete plant.
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eco friendly concretes with reduced water and Cement content mix design principles and application in practice
Construction and Building Materials, 2014Co-Authors: Tilo Proske, Stefan Hainer, Moien Rezvani, Carl-alexander GraubnerAbstract:Abstract The major environmental impact of concrete is caused by the CO 2 -emission during the Cement production. Great potential for the reduction of the impact is seen especially for concretes with normal strength. The use of superplasticizer and high reactive Cements as well as the optimization of the particle size distribution and the reduction of the water content allows a significant reduction of the Portland Cement Clinker in the concrete. Essential is the addition of mineral fillers (e.g. limestone powder) to provide an optimal paste volume. In addition the already practicable substitution of the Cement Clinker by secondary raw materials like fly-ash or furnace-slag is an appropriate opportunity but limited by the availability of these resources. In several test series the fresh and hardened concrete properties of water and Cement reduced concretes were investigated, especially the workability, the strength development, the design relevant mechanical properties as well as durability aspects like carbonation. It was shown that concretes with Cement contents lower than 125 kg/m 3 were able to meet the usual required workability, strength (app. 40 MPa) and mechanical properties. The carbonation depth of concretes with 150–175 kg/m 3 of Cement was equal or lower than the depth of the conventional reference concretes for exterior structures. The ecological advantages were identified, using the environmental performance evaluation. A reduction up to 50% in environmental impact compared with the conventional concrete and a reduction of more than 65% by using blast furnace Cement was calculated. The application in practice was verified conducting full-scale tests in a precast and ready-mix concrete plant. The special requirements on workability and early strength were fulfilled with a Cement content of 150 kg/m 3 .
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eco friendly concretes with reduced water and Cement contents mix design principles and laboratory tests
Cement and Concrete Research, 2013Co-Authors: Tilo Proske, Stefan Hainer, Moien Rezvani, Carl-alexander GraubnerAbstract:Abstract The major environmental impact of concrete is caused by CO 2 -emissions during Cement production. Great potential for reducing the impact is seen especially for concretes with normal strength. The use of superplasticizers and highly reactive Cements as well as optimization of particle-size distribution and reduction in water content allows a significant reduction in Portland Cement Clinker in the concrete. Essential is the addition of mineral fillers (e.g. limestone powder) to provide an optimal paste volume. In addition, the already practicable substitution of secondary raw materials like fly-ash or furnace-slag for Cement Clinker is an appropriate option which is however limited by the availability of these resources. In several test series the fresh and hardened concrete properties of concretes with reduced water and Cement contents were investigated, especially their workability, strength development, design-relevant mechanical properties as well as durability aspects such as carbonation. It was shown that concretes with Cement Clinker and slag contents as low as 150 kg/m 3 were able to meet the usual requirements of workability, compressive strength (approx. 40 N/mm 2 ) and mechanical properties. The carbonation depth of concretes with 150-175 kg/m 3 Clinker and slag was equal or lower than the depth of conventional reference concretes for exterior structures. The ecological advantages were identified, using environmental performance evaluation. A reduction of up to 35% in environmental impact was calculated compared with conventional concrete and of more than 60% with granulated blast-furnace slag. Practical application was verified by means of full-scale tests in a precast and ready-mix concrete plant.
G Aouad - One of the best experts on this subject based on the ideXlab platform.
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dredged sediments used as novel supply of raw material to produce Portland Cement Clinker
Cement & Concrete Composites, 2012Co-Authors: G Aouad, A Laboudigue, N Gineys, Noredine AbriakAbstract:Abstract The maintenance of waterways generates large amounts of dredged sediments that are an environmental issue. This paper focuses on the use of fluvial sediment to replace a portion of the raw materials of Portland Cement Clinker, which would otherwise come from natural resources. The mineralogy of the synthetic Cement was characterised using X-ray diffraction and scanning electron microscopy and its reactivity was followed by isothermal calorimetry. Comparisons were made to a commercial ordinary Portland Cement (CEM I 52.5). Compressive strength measurements were conducted on Cement pastes at 1, 2, 4, 7, 14, 28 and 56 days to study strength development. The results showed that Portland Cement Clinker can be successfully synthesised by using up to 39% sediment. The compressive strengths developed by the Cement made from sediment were equivalent to those obtained with the reference at early ages and 20% higher at long term.
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incorporation of trace elements in Portland Cement Clinker thresholds limits for cu ni sn or zn
Cement and Concrete Research, 2011Co-Authors: N Gineys, G Aouad, F Sorrentino, Denis DamidoAbstract:Abstract This paper aims at defining precisely, the threshold limits for several trace elements (Cu, Ni, Sn or Zn) which correspond to the maximum amount that could be incorporated into a standard Clinker whilst reaching the limit of solid solution of its four major phases (C 3 S, C 2 S, C 3 A and C 4 AF). These threshold limits were investigated through laboratory synthesised Clinkers that were mainly studied by X-ray Diffraction and Scanning Electron Microscopy. The reference Clinker was close to a typical Portland Clinker (65% C 3 S, 18% C 2 S, 8% C 3 A and 8% C 4 AF). The threshold limits for Cu, Ni, Zn and Sn are quite high with respect to the current contents in Clinker and were respectively equal to 0.35, 0.5, 0.7 and 1 wt.%. It appeared that beyond the defined threshold limits, trace elements had different behaviours. Ni was associated with Mg as a magnesium nickel oxide (MgNiO 2 ) and Sn reacted with lime to form a calcium stannate (Ca 2 SnO 4 ). Cu changed the crystallisation process and affected therefore the formation of C 3 S. Indeed a high content of Cu in Clinker led to the decomposition of C 3 S into C 2 S and of free lime. Zn, in turn, affected the formation of C 3 A. Ca 6 Zn 3 Al 4 O 15 was formed whilst a tremendous reduction of C 3 A content was identified. The reactivity of Cements made with the Clinkers at the threshold limits was followed by calorimetry and compressive strength measurements on Cement paste. The results revealed that the doped Cements were at least as reactive as the reference Cement.
Noredine Abriak - One of the best experts on this subject based on the ideXlab platform.
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dredged sediments used as novel supply of raw material to produce Portland Cement Clinker
Cement & Concrete Composites, 2012Co-Authors: G Aouad, A Laboudigue, N Gineys, Noredine AbriakAbstract:Abstract The maintenance of waterways generates large amounts of dredged sediments that are an environmental issue. This paper focuses on the use of fluvial sediment to replace a portion of the raw materials of Portland Cement Clinker, which would otherwise come from natural resources. The mineralogy of the synthetic Cement was characterised using X-ray diffraction and scanning electron microscopy and its reactivity was followed by isothermal calorimetry. Comparisons were made to a commercial ordinary Portland Cement (CEM I 52.5). Compressive strength measurements were conducted on Cement pastes at 1, 2, 4, 7, 14, 28 and 56 days to study strength development. The results showed that Portland Cement Clinker can be successfully synthesised by using up to 39% sediment. The compressive strengths developed by the Cement made from sediment were equivalent to those obtained with the reference at early ages and 20% higher at long term.