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Moises Frias - One of the best experts on this subject based on the ideXlab platform.
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Chemical and mineral transformations that occur in mine waste and washery rejects during pre-utilization calcination
International Journal of Coal Geology, 2014Co-Authors: R. Vigil De La Villa, Rosario García Giménez, Moises Frias, Sagrario Martínez-ramírez, Lucía Fernández-carrascoAbstract:Abstract The mineralogical content of coal mine waste consists primarily of inorganic compounds which can be converted into a metakaolin-based product under controlled activation conditions that is also a highly Pozzolanic Material. Activation temperatures ranging from 500 to 900 °C over 2 h retention time affect the mineralogy of coal mine waste, as well as the formation and evolution of the hydrated phases that form during the Pozzolanic reaction. The hydrated phases formed during the Pozzolanic reaction in the activated coal mine waste (ACMW)/Ca(OH) 2 system were C–S–H gels, stratlingite, tetracalcium aluminate hydrate, LDH compounds (phyllosilicate/carbonate) and monosulfoaluminate. Low temperatures (600 °C) favored the formation of LDH compounds and stratlingite; whereas monosulfoaluminate formed during the hydrated phase at higher temperatures (900 °C) during the first day of the Pozzolanic reaction, and tetracalcium aluminate hydrate appeared as the dominant crystalline phase at 7 and 28 days.
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characterisation of sugar cane straw waste as Pozzolanic Material for construction calcining temperature and kinetic parameters
Waste Management, 2007Co-Authors: Moises Frias, E Villarcocina, E ValenciamoralesAbstract:Abstract This paper reports on the influence of calcining temperature (800 and 1000 °C) on the Pozzolanic activation of sugar cane straw (SCS). The reaction kinetics of SCS ash–lime mixtures were inferred from physicochemical characteristics (X-ray diffraction patterns and thermogravimetry analysis. The fitting of a kinetic–diffusive model to the experimental data (fixed lime versus time) allowed the computing of the kinetic parameters (reaction rate constant) of the Pozzolanic reaction. Results obtained confirm that the sugar cane straw ash (SCSA) calcined at 800 and 1000 °C have properties indicative of very high Pozzolanic activity. No influence of calcining temperature on the Pozzolanic activity was observed. Also, no crystalline compounds during the Pozzolanic reaction were identified up to 90 days of reaction. Environmental durability and strength of the consequential mortars remain to be assessed.
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characterisation of sugar cane straw waste as Pozzolanic Material for construction calcining temperature and kinetic parameters
Waste Management, 2007Co-Authors: Moises Frias, E Villarcocina, E ValenciamoralesAbstract:This paper reports on the influence of calcining temperature (800 and 1000 degrees C) on the Pozzolanic activation of sugar cane straw (SCS). The reaction kinetics of SCS ash-lime mixtures were inferred from physicochemical characteristics (X-ray diffraction patterns and thermogravimetry analysis. The fitting of a kinetic-diffusive model to the experimental data (fixed lime versus time) allowed the computing of the kinetic parameters (reaction rate constant) of the Pozzolanic reaction. Results obtained confirm that the sugar cane straw ash (SCSA) calcined at 800 and 1000 degrees C have properties indicative of very high Pozzolanic activity. No influence of calcining temperature on the Pozzolanic activity was observed. Also, no crystalline compounds during the Pozzolanic reaction were identified up to 90 days of reaction. Environmental durability and strength of the consequential mortars remain to be assessed.
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morphology and properties in blended cements with ceramic wastes as a Pozzolanic Material
Journal of the American Ceramic Society, 2006Co-Authors: M Sanchez I De Rojas, J Rivera, F P Marin, Moises FriasAbstract:Divisio´n Tejas, Grupo Uralita, SpainThis paper describes the research run on ceramic Materials, andmorespecificallyfiredclayrooftiles, groundtoafinenesssuitablefor use as an active replacement for portland cements (PCs). Theutilization of waste products from calcined clay roof tiles as aPozzolanic Material in the cement manufacture is studied. OneofthefirstMaterialsusedaspozzo lansinthehistorywasthermal-treated clay, a Material similar to the calcined clay precastelements. For this study, the Materials selected are clay productsthat have been eliminated for different reasons: a wrong tem-perature inside the kiln, dimensional and mechanical failures, anddurability loss. The results showed that these products have goodPozzolanic properties; at an early age, the Pozzolanic activity wasfound to be higher than fly ash, although it was lower than silicafume. The morphology of clay tile–PC pastes are similar to themorphology of the pastes containing other Pozzolanic Materials.Hydrated calcium aluminate products are generated when thepreparation method yields less compact pastes with a greatervoids’ volume to accommodate these products. The hydratedcalcium aluminate phases were analyzed using scanning electro-nic microscopy and X-ray diffraction techniques.I. Introduction
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recycling of silicomanganese slag as Pozzolanic Material in portland cements basic and engineering properties
Cement and Concrete Research, 2006Co-Authors: Moises Frias, Isabel Sanchez M De Rojas, Jesus Santamaria, Cristina RodriguezAbstract:Abstract Correct use of SiMn slags requires a detailed knowledge of their properties, as chemical and mineralogical composition, Pozzolanic activity, reaction kinetics, setting time, volume expansion and strength play important role in the final valorisation of SiMn slag as Pozzolanic Material. This kind of slag is formed mainly of SiO2 and CaO, followed by Al2O3 and MnO which sum is nearly 90%. Sulphites content of 0.42% was detected. The main crystalline compound identified in SiMn slag is akermanite. The results obtained show that SiMn slag blended cements do not show volume instability, the strength values are very close to the control mortar and they have a denser matrix. SiMn blended matrices fulfil standard specification requirements (chemical, physical and mechanical ones) and show that SiMn slag is suitable for blended cements manufacture.
Chai Jaturapitakkul - One of the best experts on this subject based on the ideXlab platform.
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effect of ground bagasse ash on mechanical and durability properties of recycled aggregate concrete
Materials & Design, 2012Co-Authors: Rattapon Somna, Chai Jaturapitakkul, Pokpong Rattanachu, Wichian ChaleeAbstract:Abstract In this study, bagasse ash, which is a large disposal landfill waste from sugar mill industries, is utilized as a Pozzolanic Material to improve the mechanical properties and durability of recycled aggregate concrete. Ground bagasse ash (GBA) was used to replace Portland cement Type I at the percentages of 20, 35, and 50 by weight of binder. Compressive strength, modulus of elasticity, water permeability, and chloride penetration depth of the concretes were determined. The results revealed that the modulus of elasticity of recycled aggregate concrete with and without GBA was lower than that of conventional concrete by approximately 19%. GBA can be used effectively to reduce the water permeability of recycled aggregate concrete. The increase of GBA content in recycled aggregate concrete results in a significant decrease in chloride penetration depths. In addition, the mechanical properties and durability of recycled aggregate concrete were efficiently improved by using 20% of GBA in the concrete mixtures.
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filler effect of fine particle sand on the compressive strength of mortar
International Journal of Minerals Metallurgy and Materials, 2011Co-Authors: Chai Jaturapitakkul, Jatuphon Tangpagasit, Sawang Songmue, Kraiwood KiattikomolAbstract:The river sand, which is a non-Pozzolanic Material, was ground into 3 different particle sizes. Portland cement type I was replaced by the ground river sands at 10wt%–40wt% of binder to cast mortar. Compressive strengths of mortar were investigated and the filler effect of different fine particles of sand on the compressive strength of mortar was evaluated. The results show that the compressive strength of mortar contributed from the filler effect of smaller particles is higher than that of the coarser ones. The difference in compressive strength of mortar tends to be greater as the difference in ground river sand fineness increases. The results also suggest that ASTM C618 specification is not practically suitable for specifying pozzolan in concrete since the strength activity index of mortar containing ground river sand (high crystalline phase) with 33.8wt% of particles retained on a 45-μm sieve can pass the strength requirement.
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strength drying shrinkage and water permeability of concrete incorporating ground palm oil fuel ash
Cement & Concrete Composites, 2010Co-Authors: Weerachart Tangchirapat, Chai JaturapitakkulAbstract:Abstract In this study, palm oil fuel ash (POFA) was used as a Pozzolanic Material in concrete. The POFA was ground to obtain two different finenesses: coarse (CP) and fine (FP). A portion of ordinary type I Portland cement (OPC) was replaced by CP and FP at 10%, 20%, and 30% by weight of binder to cast concrete. Compressive strength, modulus of elasticity, drying shrinkage, and water permeability of concretes containing ground POFA were measured. The results showed that the compressive strength of the concrete increased with the fineness of the POFA. With 10% and 30% replacement of OPC by CP and FP, respectively, the compressive strength of the resulting concrete was as high as that of OPC concrete at 90 days. Moreover, the use of 10–30% of FP as a cement replacement in concrete reduced its drying shrinkage and water permeability. Finally, there was also a strong correlation between the compressive strength and the water permeability of ground POFA concrete.
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utilization of bagasse ash as a Pozzolanic Material in concrete
Construction and Building Materials, 2009Co-Authors: Nuntachai Chusilp, Chai Jaturapitakkul, Kraiwood KiattikomolAbstract:Abstract The physical properties of concrete containing ground bagasse ash (BA) including compressive strength, water permeability, and heat evolution, were investigated. Bagasse ash from a sugar factory was ground using a ball mill until the particles retained on a No. 325 sieve were less than 5wt%. They were then used as a replacement for Type I Portland cement at 10, 20, and 30wt% of binder. The water to binder (W/B) ratio and binder content of the concrete were held constant at 0.50 and 350 kg/m3, respectively. The results showed that, at the age of 28 days, the concrete samples containing 10–30% ground bagasse ash by weight of binder had greater compressive strengths than the control concrete (concrete without ground bagasse ash), while the water permeability was lower than the control concrete. Concrete containing 20% ground bagasse ash had the highest compressive strength at 113% of the control concrete. The water permeability of concrete decreased as the fractional replacement of ground bagasse ash was increased. For the heat evolution, the maximum temperature rise of concrete containing ground bagasse ash was lower than the control concrete. It was also found that the maximum temperature rise of the concrete was reduced 13, 23, and 33% as compared with the control concrete when the cement was replaced by ground bagasse ash at 10, 20, and 30wt% of binder, respectively. The results indicate that ground bagasse ash can be used as a Pozzolanic Material in concrete with an acceptable strength, lower heat evolution, and reduced water permeability with respect to the control concrete.
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use of palm oil fuel ash as a supplementary cementitious Material for producing high strength concrete
Construction and Building Materials, 2009Co-Authors: Weerachart Tangchirapat, Chai Jaturapitakkul, Prinya ChindaprasirtAbstract:Abstract The objective of this study is to investigate the use of ground palm oil fuel ash with high fineness (GPA) as a Pozzolanic Material to produce high-strength concrete. Samples were made by replacing Type I Portland cement with various proportions of GPA. Properties such as the compressive strength, drying shrinkage, water permeability, and sulfate resistance, were then investigated. After aging for 28 days, the compressive strengths of these concrete samples were found to be in the range of 59.5–64.3 MPa. At 90-day the compressive strength of concrete containing GPA 20% was as high as 70 MPa. The drying shrinkage and water permeability were lower than those of high-strength concrete made from Type I Portland cement. When the concrete samples were immersed in a 10% MgSO 4 solution for 180 days, the sulfate resistance in terms of the expansion and loss of compressive strength was improved. The results indicated that GPA is a reactive Pozzolanic Material and can be used as a supplementary cementitious Material for producing high-strength concrete.
Jordi Payá - One of the best experts on this subject based on the ideXlab platform.
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Valorisation of sugarcane bagasse ash (SCBA) with high quartz content as Pozzolanic Material in Portland cement mixtures
Consejo Superior de Investigaciones Científicas, 2018Co-Authors: A. M. Pereira, Jorge Luís Akasaki, José Monzó, C.b. J. Moraes, J.b. M. Moraes, M. M. Tashima, L. Soriano, Jordi PayáAbstract:Portland cement (OPC) production is one of the most contaminating greenhouse gas producing activities. In order to reduce OPC consumption, several alternatives are being assessed, and the use of Pozzolanic Material is one of them. This paper presents study on the reactivity of sugarcane bagasse ash (SCBA), a residue from sugarcane industry, as a Pozzolanic Material. In order to evaluate SCBA reactivity, it was mixed in pastes with hydrated lime and OPC, which were microstructurally characterised. These studies showed that SCBA presents some Pozzolanic characteristics. Studies on mortars in which OPC was replaced by SCBA in the range 10–30% were also carried out. Replacement in the range 15–20% yielded the best behaviour in terms of compressive strength. Finally, it can be concluded this ash could be valorised despite its relative low Pozzolanic reactivity
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Pozzolanic Reactivity Studies on a Biomass-Derived Waste from Sugar Cane Production: Sugar Cane Straw Ash (SCSA)
ACS Sustainable Chemistry & Engineering, 2016Co-Authors: J.c.b. Moraes, José Luiz Pinheiro Melges, Jorge Luís Akasaki, Mauro Mitsuuchi Tashima, Lourdes Soriano, José Monzó, Jordi PayáAbstract:Biomass has gained in importance as an energy source in recent years. One of the crops that presents interesting opportunities with regard to biomass is sugar cane. In Brazil, sugar cane production is increasing for alcohol and sugar manufacture. Some byproducts, such as sugar cane straw, also are obtained during harvesting. Because of the calorific value of the sugar cane straw, its use as biomass is increasing. After the straw is burned to produce energy, an ash is obtained: sugar cane straw ash (SCSA). This waste needs an appropriate destination, and since the recent publication of successful studies using biomass derived-ashes as Pozzolanic Material, the present study aimed to assess the Pozzolanic reactivity of sugar cane straw ash. The Pozzolanic activity was assessed using a new and simple recently proposed method: evaluation of the electrical conductivity of calcium hydroxide (CH) and pozzolan suspensions, in which solid CH is initially present. These results were compared to those of two other we...
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assessment of sugar cane straw ash scsa as Pozzolanic Material in blended portland cement microstructural characterization of pastes and mechanical strength of mortars
Construction and Building Materials, 2015Co-Authors: J.c.b. Moraes, José Luiz Pinheiro Melges, Jorge Luís Akasaki, José Monzó, Jordi Payá, L. Soriano, M V Borrachero, M. M. TashimaAbstract:Abstract The aim of this paper is to assess the Pozzolanic reactivity of sugar cane straw ash (SCSA) obtained through an auto-combustion process and the mechanical properties of SCSA-containing systems. Characterization of SCSA (X-ray diffraction, chemical composition, particle size, and microscopy) and reactivity studies on hydrated lime/SCSA and Portland cement/SCSA pastes through infrared spectroscopy, thermogravimetric analysis, and microscopy demonstrated the high Pozzolanic activity. This reactivity made it possible to achieve good mechanical properties in mortars in which 15–30% of the cement was replaced by SCSA. After 90 days of curing, the SCSA fixed 100% of the lime present in lime/SCSA pastes, and the compressive strength of mortars containing SCSA reached 44 MPa, a value similar to those found for control mortars after the same number of curing days. The results for the microstructural and mechanical properties showed that SCSA is a good Pozzolanic Material.
E Valenciamorales - One of the best experts on this subject based on the ideXlab platform.
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characterisation of sugar cane straw waste as Pozzolanic Material for construction calcining temperature and kinetic parameters
Waste Management, 2007Co-Authors: Moises Frias, E Villarcocina, E ValenciamoralesAbstract:Abstract This paper reports on the influence of calcining temperature (800 and 1000 °C) on the Pozzolanic activation of sugar cane straw (SCS). The reaction kinetics of SCS ash–lime mixtures were inferred from physicochemical characteristics (X-ray diffraction patterns and thermogravimetry analysis. The fitting of a kinetic–diffusive model to the experimental data (fixed lime versus time) allowed the computing of the kinetic parameters (reaction rate constant) of the Pozzolanic reaction. Results obtained confirm that the sugar cane straw ash (SCSA) calcined at 800 and 1000 °C have properties indicative of very high Pozzolanic activity. No influence of calcining temperature on the Pozzolanic activity was observed. Also, no crystalline compounds during the Pozzolanic reaction were identified up to 90 days of reaction. Environmental durability and strength of the consequential mortars remain to be assessed.
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characterisation of sugar cane straw waste as Pozzolanic Material for construction calcining temperature and kinetic parameters
Waste Management, 2007Co-Authors: Moises Frias, E Villarcocina, E ValenciamoralesAbstract:This paper reports on the influence of calcining temperature (800 and 1000 degrees C) on the Pozzolanic activation of sugar cane straw (SCS). The reaction kinetics of SCS ash-lime mixtures were inferred from physicochemical characteristics (X-ray diffraction patterns and thermogravimetry analysis. The fitting of a kinetic-diffusive model to the experimental data (fixed lime versus time) allowed the computing of the kinetic parameters (reaction rate constant) of the Pozzolanic reaction. Results obtained confirm that the sugar cane straw ash (SCSA) calcined at 800 and 1000 degrees C have properties indicative of very high Pozzolanic activity. No influence of calcining temperature on the Pozzolanic activity was observed. Also, no crystalline compounds during the Pozzolanic reaction were identified up to 90 days of reaction. Environmental durability and strength of the consequential mortars remain to be assessed.
J.c.b. Moraes - One of the best experts on this subject based on the ideXlab platform.
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Pozzolanic Reactivity Studies on a Biomass-Derived Waste from Sugar Cane Production: Sugar Cane Straw Ash (SCSA)
ACS Sustainable Chemistry & Engineering, 2016Co-Authors: J.c.b. Moraes, José Luiz Pinheiro Melges, Jorge Luís Akasaki, Mauro Mitsuuchi Tashima, Lourdes Soriano, José Monzó, Jordi PayáAbstract:Biomass has gained in importance as an energy source in recent years. One of the crops that presents interesting opportunities with regard to biomass is sugar cane. In Brazil, sugar cane production is increasing for alcohol and sugar manufacture. Some byproducts, such as sugar cane straw, also are obtained during harvesting. Because of the calorific value of the sugar cane straw, its use as biomass is increasing. After the straw is burned to produce energy, an ash is obtained: sugar cane straw ash (SCSA). This waste needs an appropriate destination, and since the recent publication of successful studies using biomass derived-ashes as Pozzolanic Material, the present study aimed to assess the Pozzolanic reactivity of sugar cane straw ash. The Pozzolanic activity was assessed using a new and simple recently proposed method: evaluation of the electrical conductivity of calcium hydroxide (CH) and pozzolan suspensions, in which solid CH is initially present. These results were compared to those of two other we...
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assessment of sugar cane straw ash scsa as Pozzolanic Material in blended portland cement microstructural characterization of pastes and mechanical strength of mortars
Construction and Building Materials, 2015Co-Authors: J.c.b. Moraes, José Luiz Pinheiro Melges, Jorge Luís Akasaki, José Monzó, Jordi Payá, L. Soriano, M V Borrachero, M. M. TashimaAbstract:Abstract The aim of this paper is to assess the Pozzolanic reactivity of sugar cane straw ash (SCSA) obtained through an auto-combustion process and the mechanical properties of SCSA-containing systems. Characterization of SCSA (X-ray diffraction, chemical composition, particle size, and microscopy) and reactivity studies on hydrated lime/SCSA and Portland cement/SCSA pastes through infrared spectroscopy, thermogravimetric analysis, and microscopy demonstrated the high Pozzolanic activity. This reactivity made it possible to achieve good mechanical properties in mortars in which 15–30% of the cement was replaced by SCSA. After 90 days of curing, the SCSA fixed 100% of the lime present in lime/SCSA pastes, and the compressive strength of mortars containing SCSA reached 44 MPa, a value similar to those found for control mortars after the same number of curing days. The results for the microstructural and mechanical properties showed that SCSA is a good Pozzolanic Material.