Journal articles: 'Calcination of hydrailic lime'

1

Leontakianakos, G., I. Baziotis, G. Ekonomou, G. Delagrammatikas, C. T. Galbenis, and S. Tsimas. "A CASE STUDY OF DIFFERENT LIMESTONES DURING QUICK LIME AND SLAKED-LIME PRODUCTION." Bulletin of the Geological Society of Greece 43, no. 5 (July 31, 2017): 2485. http://dx.doi.org/10.12681/bgsg.11654.

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We have examined 5 different limestones in order to study their behavior i) during calcination at different temperatures (900, 1050 and 1200°C for 30 min) and ii) after hydration of quick limes derived to slaked lime. Quick limes calcined at 900°C show the lower reactivity values. This could be related to the low calcination temperature or to the short calcination time of 30 min which was unable to produce enough lime. The samples calcined at temperatures of 1200°C are less reactive compared to the hydrated limes which were prepared by hydration of quick lime calcined at 1050°C, indicating by parameters such as the (CaO+MgO)Lime, the time required to become the temperature maximum and the reactivity rate. These, probably could be due to crystal growth at relative high temperatures.

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Cao, Jian Xin, Fei Liu, Qian Lin, Yu Zhang, Yong Gang Dong, and Ling Ke Zeng. "Effect of Calcination Temperature on Mineral Composition of Carbide Slag, Lime Activity and Synthesized Xonotlite." Key Engineering Materials 368-372 (February 2008): 1545–47. http://dx.doi.org/10.4028/www.scientific.net/kem.368-372.1545.

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The calcined carbide slag was used to prepare xonotlite by replacing quicklime as the calcareous materials. Effects of calcination temperature on the mineral composition of the carbide slag, lime activity and synthesized xonotlite were studied. The results indicated that carbide slag after proper calcination can be used to prepare xonotlite. Calcination temperature has no effect on the synthesized xonotlite, but has a great impact on lime activity and morphology of secondary particles of xonotlite.

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Zhongda, Tian, Li Shujiang, Wang Yanhong, and Wang Xiangdong. "SVM predictive control for calcination zone temperature in lime rotary kiln with improved PSO algorithm." Transactions of the Institute of Measurement and Control 40, no. 10 (September 18, 2017): 3134–46. http://dx.doi.org/10.1177/0142331217716983.

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To improve the control performance of calcination zone temperature in a lime rotary kiln, a predictive control method based on a support vector machine (SVM) and improved particle swarm optimization (PSO) algorithm is proposed. As high-temperature thermal equipment, the lime rotary kiln requires accurate modelling because of its complex non-linearity and long delay characteristics. SVM has strong normalization and good learning ability compared with other modelling models such as neural network, partial least squares model and other non-linear regression models, which can avoid overfitting and local minimization problems. At the same time, it is sometimes difficult to obtain a large number of production sample data of lime rotary kiln. The modelling process based on SVM requires only a small amount of sample data. SVM is appropriate for the modelling of calcination zone temperature of the lime rotary kiln. The predictive control method in this paper utilizes SVM to establish a non-linear prediction model of calcination zone temperature of the lime rotary kiln. The calcination zone temperature can be achieved by output feedback of input control variables, the error and the error correction. The performance index function is established by the control deviations and control variables. An improved PSO algorithm with better convergence speed and accuracy is employed to obtain optimal control laws by rolling optimization. The stability of the control method has also been demonstrated. The proof process shows that the control method of this paper is asymptotically stable. The simulation results show that the prediction error of calcination zone temperature based on SVM is within ±20°C and the prediction accuracy is better. The model of calcination zone temperature in the lime rotary kiln based on SVM has good performance. The proposed predictive control method can make the output value of the calcination zone temperature of the lime rotary kiln fast and stable to track the change of the reference value. At the same time, in the presence of interference, the system can also track the reference value. The average single step rolling optimization time of the control variables needs to be 0.29 s, which can be used for the practical applications. The simulation results show that the proposed control method is effective.

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Yur'ev, Boris, and Vyacheslav Dudko. "Determination of Key Parameters Required to Optimize Calcination Process in Ferrous Metallurgy Heating Plants." Solid State Phenomena 316 (April 2021): 282–87. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.282.

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Lime is the product of calcination. Its formation is always related to removal of carbon dioxide generated in the course of carbonate decomposition. Ferrous metallurgy, construction material, chemical and food industry companies account for about 90 % of lime produced in the country. Ferrous metallurgy is the major consumer of commercial lime using up to 40 % of all produced lime. Currently, despite occurrence of new binding and artificially produced chemical compounds, lime remains the major chemical compound produced by the industry in terms of output. Various units (shaft, rotary tubular kilns and fluidized bed kilns) are used for calcination. Shaft kilns are used the most widely. Considering continuously growing demand for lime, the need occurs for intensification of the burning process and optimization of the shaft kiln operating conditions. This requires knowledge of calcination physicochemical and heat transfer process mechanisms. Thus, the work deals with the issues related to determination of the optimal specific fuel consumption for burning of limestone from a particular deposit. It may be done only basing on thermal calculations for an operating shaft kiln, what, in its turn, causes the need for determination of the whole set of limestone and lime heat transfer properties. The obtained work results may be used to optimize the operating conditions of not only shaft but also rotary kilns intended for limestone heat treatment.

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Adimarta, Trian, and M. Nopriyanti. "CHARACTERIZATION OF CALCIUM (Ca) BY USING SPECTROFOTOMETER UV-Vis FROM SIRIHLIME WITH CALCINATION METHODS OF MANGROVE CLAMSHELL IN KETAPANG." JURNAL PERTANIAN 11, no. 1 (April 28, 2020): 25. http://dx.doi.org/10.30997/jp.v11i1.2163.

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Clamshell is a solid waste generated by shells that are not utilized and cannot be consumed because they have hard properties. The purpose of this study was to determine the process of making sirihlime from mangrove shells using calcination method, characterizing calcium (Ca) using spectrophotometer UV-Vis.Method of making sirihlime from clamshell with calcination process. The calcination used was 1000oC for 3 hours, 800oC for 5 hours and 600oC for 7 hours. The results of the process of calcination of raw shells in the form of lime (CaO) and then added hot water to the Ca(OH)2 sirihlime was then characterized by calcium (Ca) using spectrophotometer UV-Vis 1800.Spectrofotometer UV-Vis of sirih lime demonstrated that maximum wavelength obtained is 529. The linier regression of the standart curve y = 1,021x + 1,6846 with a value of r2 = 0,7344. The calcium mineral from sirih lime at temperature 1000 oC for 3 hours an average of 1,536 mg/L, temperature 800oC for 5 hours an average of 2,2765 mg/L and temperature 600oC for 7 hours an average of 1,1159 mg/L.

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Leontakianakos, G., I. Baziotis, E. Profitis, E. Chatzitheodoridis, and S. Tsimas. "Assessment of the quality of calcination of marbles from Thassos Island using Raman spectroscopy and X-Ray Diffraction." Bulletin of the Geological Society of Greece 47, no. 4 (September 5, 2013): 2040. http://dx.doi.org/10.12681/bgsg.11088.

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The degree of calcination of a dolomitic and a calcitic marble from Thassos Island, was investigated, by combining both Raman spectroscopy (RS) and X-Ray diffraction (XRD) techniques. The samples were prepared in isometric 2 cm cubes and calcined at three different temperatures, 900, 1050 and 1200 0C for 2 hours in order to produce quick lime. RS was applied at the lime sample’s surface and inner (near core) part after gently crushing. XRD was applied on the bulk rock specimens in order to verify the transformation process during heating of the raw material. Quality control of the applied calcination procedure is provided through the hydration of quick lime. The rise in solution temperature suggests the chemical “reactivity” of the produced slaked lime. Raman and XRD results revealed the presence of unburned quantities of calcite and dolomite on samples that were calcined at 900 0C. Furthermore, temperatures of 1050 and 1200 0C have shown comparable mineralogical features signifying evenly the conversion of carbonate minerals to their oxide equivalents, proving the completion of the calcination process. Finally, reactivity tests showed that the highest reactivity value of the produced quicklime, for both marbles is observed at the temperature of 1050 0C.

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Meier, Anton, Enrico Bonaldi, Gian Mario Cella, and Wojciech Lipinski. "Multitube Rotary Kiln for the Industrial Solar Production of Lime." Journal of Solar Energy Engineering 127, no. 3 (April 29, 2005): 386–95. http://dx.doi.org/10.1115/1.1979517.

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We designed and tested a scaleable solar multitube rotary kiln to effect the endothermic calcination reaction CaCO3→CaO+CO2 at above 1300K. The indirect heating 10-kW reactor prototype processes 1-5mm limestone particles, producing high purity lime of any desired reactivity and with a degree of calcination exceeding 98%. The reactor’s efficiency, defined as the enthalpy of the calcination reaction at ambient temperature (3184kJkg−1) divided by the solar energy input, reached 30%–35% for solar flux inputs of about 2000kWm−2 and for quicklime production rates up to 4kgh−1. The use of concentrated solar energy in place of fossil fuels as the source of process heat has the potential of reducing by 20% CO2 emissions in a state-of-the-art lime plant and by 40% in a conventional cement plant.

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Zhang, Li, Bo Gao, and Zeng Jun Bao. "Modeling Method Based on Subspace Identification for Lime Kiln Calcination Process." Applied Mechanics and Materials 229-231 (November 2012): 1882–85. http://dx.doi.org/10.4028/www.scientific.net/amm.229-231.1882.

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To deal with the modeling problem of the lime kiln calcination process, we propose a model describing the relationship between process states and outputs. By analyzing the strongly coupled features in the process, we construct a relationship model using subspace identification method which takes two inputs including the second air flow and gas flow, and two outputs including the calcining zone temperature and kiln tail temperature. The simulation shows that this model is of high accuracy for describing the characteristics of lime kiln calcination process.

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Chilakala, Ramakrishna, Thriveni Thenepalli, Seongho Lee, Hong Ha Thi Vu, Lai Quang Tuan, Jeongyun Kim, and Ji Whan Ahn. "Sequential In-Situ Carbonation Process for the Preparation of Hand Sheets with Waste Lime Mud." Reactions 1, no. 1 (June 17, 2020): 3–15. http://dx.doi.org/10.3390/reactions1010002.

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In the pulp and paper industry, the white liquor obtained from the causticizing green liquor in the smelting process mostly contains NaOH and Na2S. These chemicals are returned to the digester for reuse in the pulping process. The lime mud (LM) material is obtained from the reaction of the causticization process in paper industries. It is mainly composed of CaCO3; it appears with a green color with a high moisture content; and it has a small proportion of impurities such as non-process elements, for example Fe, Na, Mg, Al, Si, P, and S oxides and other toxic metals. This lime mud has poor whiteness with less efficiency due to its contaminated with impurities. The recycling or reutilizing process for lime mud and solid wastes are minimizing its toxic effect on the environment. The present study proposed to improve the whiteness of the waste lime mud by the calcination and hydration process at high temperatures and reutilizing it for hand sheets, making the process improve the paper brightness. In this study, we used a lime mud sample for calcination at 1000 °C and 1200 °C for 2 h and hydration at different times (3–24 h) with different temperatures (30–80 °C) and measured the powder whiteness and hand sheet brightness. The results indicated that after the calcination and hydration process, the lime mud sample whiteness was improved and that re-utilization with pulp for making hand sheets also can improve the paper brightness. It can be concluded that waste lime mud sample purification and the re-utilization process are more advantageous in paper industries.

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Ferraz, E., J. A. F. Gamelas, J. Coroado, C. Monteiro, and F. Rocha. "Exploring the potential of cuttlebone waste to produce building lime." Materiales de Construcción 70, no. 339 (July 20, 2020): 225. http://dx.doi.org/10.3989/mc.2020.15819.

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The goal of this study is to find a practicable way to recycle cuttlebone waste in the production of lime. It was studied the behavior of calcium oxide obtained from the calcination of this waste at 900, 1000 and 1100 ºC and, after wet slaking, the produced lime was characterized. All the results were compared to calcium oxide or to hydrated lime obtained from commercial limestone. According to the slaking results, the waste and the limestone calcined at 1000 ºC achieved the R4 (around 13 min to reach 60 ºC) and R5 (60 ºC in 25 s) reactivity class, respectively. Changing the calcination temperature to 900 or 1100 ºC did not promote an increase in the reactivity of the calcined waste. Although less reactive than the calcined limestone, the calcined cuttlebone can be transformed without significant constraint into building lime, since this construction material fulfills the relevant physic-chemical standard specifications.

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11

Slezak, Radosław, Liliana Krzystek, Piotr Dziugan, and Stanisław Ledakowicz. "Co-Pyrolysis of Beet Pulp and Defecation Lime in TG-MS System." Energies 13, no. 9 (May 6, 2020): 2304. http://dx.doi.org/10.3390/en13092304.

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The process of pyrolysis of beet pulp, a by-product after the extraction of raw sugar from sugar beet, with the addition of defecation lime was studied in a thermobalance coupled with a mass spectrometer. The beet pulp pyrolysis process took place completely at 600 °C, and the resulting char, tar and gas were characterized by higher heating values of 23.9, 21.6 and 7.77 MJ/kg, respectively. The addition of the defecation lime to beet pulp caused both an increase in the char production yield and a decrease in the tar production yield. At the same time, the higher heating value of char and tar decreased along with the increase of defecation lime added to the sample. The deconvolution of derivative thermogravimetric (DTG) curves allowed us to identify the basic components of beet pulp, for which the activation energy by isoconversion method was calculated. The 20 wt.% addition of defecation lime caused an increase of the activation energy by about 18%. Further increase in the defecation lime content resulted in a reduction of activation energy. At the temperature above 600 °C, calcination of calcium carbonate contained in defecation lime occurred. The CO2 produced during calcination process did not cause auto-gasification of char.

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12

Hai Do, Duc, and Eckehard Specht. "Measurement and Simulation of Lime Calcination in Normal Shaft Kiln." Materials Performance and Characterization 1, no. 1 (September 2012): 104351. http://dx.doi.org/10.1520/mpc104351.

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13

Clay, David T., and Nancy J. Sell. "MAPPS fluidized bed calcination of lime mud: modelling for design." Applied Mathematical Modelling 13, no. 8 (August 1989): 485–93. http://dx.doi.org/10.1016/0307-904x(89)90097-8.

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14

DA ROSA, Flávia Sapper, Andressa LHAMBY, Vinicyus Mourão Monteiro GUILLET, Marcos Antônio KLUNK, and Nattan Roberto CAETANO. "THERMAL AND ECONOMIC ANALYSIS OF LIME PRODUCTION." SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 28, no. 29 (December 20, 2020): 46–54. http://dx.doi.org/10.48141/sbjchem.v28.n29.2020.06_rosa_pgs_46_54.pdf.

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The ore beneficiation process uses little technology, but mining companies have high economic performance. As an energy source, firewood plays a fundamental role due to its simple storage, low cost, great availability of forests, and lack of processing. Thus, the present work aims to analyze the consumption of firewood as fuel and possible improvements in the process for the production of lime in terms of harnessing raw materials and costs. Calcium oxide is obtained from the thermal decomposition of calcium and magnesium carbonates obtained from dolomitic deposits of limestone (CaCO3 : CaMgCO3). After CaO extraction, it is subjected to a calcination process, removing carbon dioxide (CO2) in ovens that work at temperatures between 900 and 1200°C. The source of energy applied to the calcination furnaces in the analyzed area is wood. The wood has a calorific value between 2,250 and 2,700 Kcal/Kg, but the moisture content responsible for the thermal variation must be considered. The firewood burning process was carried out in a ravine type oven where the temperature at which operators are exposed to heat was evaluated. The results indicated that the cooking time dropped by 20% as the amount of wood is fed into the oven. This increase represents a significant gain in lime production, thus leading to a higher profit for the company.

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Grant, J., G. L. Pesce, R. J. Ball, M. Molinari, and S. C. Parker. "An experimental and computational study to resolve the composition of dolomitic lime." RSC Advances 6, no. 19 (2016): 16066–72. http://dx.doi.org/10.1039/c5ra25451e.

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CHRISTIDIS, G., G. TRIANTAFYLLOU, and T. MARKOPOULOS. "Evaluation of an Upper Cretaceous limestone from the area of Arta for lime production." Bulletin of the Geological Society of Greece 34, no. 3 (January 1, 2001): 1169. http://dx.doi.org/10.12681/bgsg.17178.

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Calcination of an Upper Cretaceous limestone from the Ionian Unit at 700-1100°C for 1-4 hours yielded very reactive lime end products. Lime formation was monitored by means of kinetic curves and TTT diagrams. Particle size seems to control the onset of lime crystallization at low temperatures, but is of minor importance at higher temperatures. With the experimental setting used, lime formation was completed at 900 °C. The specific surface area of the end products increases with firing temperature up to 800 °C, decreasing thereafter. Decrepitation of lime increases gradually with firing temperature. Hydration temperature during slaking increases rapidly up to 900 °C being relatively constant thereafter. Sintering and production of fines during firing control the physical properties of lime.

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Villachica, Carlos A., and Joyce G. Villachica. "TECHNOLOGY DEVELOPMENT FOR STRONG REDUCTION OF ENERGY CONSUMPTION AND CO2 EMISSION IN LIME AND CEMENT MANUFACTURE." GeoScience Engineering 63, no. 3 (September 26, 2017): 1–7. http://dx.doi.org/10.1515/gse-2017-0011.

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Abstract The cement and lime industries are responsible for 8% of global CO2 emissions [1]. 35% of this CO2 share comes from fuel combustion to heat and decompose limestone to produce lime or “clinker” in an open atmosphere while the remaining 65% comes from limestone rock itself. Due to the new technology, high grades of both lime and CO2 were obtained faster and at much lower than conventional temperatures and CO2 was fully captured and utilized when using an HEVA reactor for limestone calcination. Clinker, a precursor of cement, was partly obtained at lower temperature when starting from HEVA lime and fine quartz after mechanochemical pretreatment.

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Soares, Marcela Maira N. S., Flávia S. J. Poggiali, Augusto Cesar S. Bezerra, Roberto B. Figueiredo, Maria Teresa P. Aguilar, and Paulo Roberto Cetlin. "The effect of calcination conditions on the physical and chemical characteristics of sugar cane bagasse ash." Rem: Revista Escola de Minas 67, no. 1 (March 2014): 33–39. http://dx.doi.org/10.1590/s0370-44672014000100005.

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The effect of calcination temperature and air flow on the content of organic material, morphology of particles, degree of crystallinity and the reactivity with lime solution of the sugar cane bagasse ash is evaluated. The results show that the long fibers of the bagasse and organic material are retained when calcination occurs without sufficient air flow. Calcining with forced air-flow breaks the fibers, removes organic material and produces fine particles at a temperature of 600ºC. The non-organic material observed in the ash displays a high degree of crystallinity. Experiments show that the crystalline structure observed in the ashes is due to adhered sand which was not previously washed away. The reduction on the conductivity in lime solution and X-rays diffraction pattern suggest that amorphous silica is formed at temperatures lower than 600ºC and cristobalite is formed at higher temperatures.

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Ucurum, Metin, Volkan Arslan, Huseyin Vapur, Oktay Bayat, and Vedat Arslan. "Recovery of unburned carbon from lime calcination process using statistical technique." Fuel Processing Technology 87, no. 12 (December 2006): 1117–21. http://dx.doi.org/10.1016/j.fuproc.2006.08.005.

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Silveira, M. A. C. W. da, J. A. M. da Luz, G. L. de Faria, and F. M. P. Coutinho. "Calcination thermokinetics of three Brazilian limestones." Cerâmica 66, no. 379 (September 2020): 297–306. http://dx.doi.org/10.1590/0366-69132020663792910.

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Abstract Limestone and lime producers inadvertently generate a considerable amount of fine material during their processing, consequently becoming a great environmental liability. As far as the industrial calcination process is concerned, there is still a need for an experimental survey on Arrhenius law parameters, as apparent frequency factor and activation energy, referring to Brazilian limestones. The knowledge of these thermokinetic parameters may contribute to energy saving during the industrial calcination process, as well as for allowing the use of limestone fines in other industrial applications. This study aimed to characterize three Brazilian limestones by focusing on their laboratory-scale calcination using both quasi-isothermal and non-isothermal methods to estimate their kinetic parameters. The non-isothermal method (by thermogravimetric analyses) allowed estimating the activation energy for each limestone through the high calcination rate ranges. However, the kinetic parameters estimated by the quasi-isothermal method turned out in lower values, indicating the need to control the reactor atmosphere.

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Qiu, Yu Chong, Ke Hui Qiu, Jun Han Li, and Pei Cong Zhang. "Preparation of Al₂O₃ from the Nepheline Ore of Nanjiang County, Sichuan Province of China." Materials Science Forum 814 (March 2015): 230–34. http://dx.doi.org/10.4028/www.scientific.net/msf.814.230.

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Crystalline alumina samples with Al2O3 content of 95.23 wt.% were prepared directly from the nepheline ore in Nanjiang county, Sichuan province of China. Four steps were involved in the experiment of alumina preparation, including calcination, dissolution, carbonation and re-calcination. Lime was used in the calcination process with the nepheline concentrates powders to generate soluble aluminates and insoluble silicates. NaOH solution was used as the mother solution in the dissolution process. CO2 was introduced into the solution to precipitate the Al (OH)3 precursor, which was then fired to obtain crystalline alumina. Among the crystalline alumina obtained three phases of crystals existed which were detected by XRD and SEM, including δ-Al2O3 as the major phase, while θ-Al2O3 and κ-Al2O3 as the minor phases. Various crystal phases of alumina could be ascribed to the purity and crystal structure of precursor, as well as the re-calcination temperature and time.

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Feng, Zhi Gang, Jiang Liu, and Hui Juan Li. "Preventing Sintering Bricks of Purple Sandy Shale from Lime Brust: Experimental Research on Fixing Calcium with Sulfur." Advanced Materials Research 189-193 (February 2011): 580–84. http://dx.doi.org/10.4028/www.scientific.net/amr.189-193.580.

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Simulating current sintering process used by the brickkiln, at 800 °C, i.e. calcination temperature of the marginal area of the brickkiln, this work conducted experimental research on preventing sintering bricks of purple sandy shale from lime brust through fixing free CaO in sintering bricks with sulfur of high-sulfur coal. It is concluded that the critical content of CaCO3 in purple sandy shale, causing lime brust of sintering bricks, is 24% by weight, when it is below this, lime brust commonly doesn’t occur; sulfur of high-sulfur coal (if necessarily, adulterated with pyrite ore) may effectively lower the concentration of free CaO in sintering bricks, accordingly eliminate or weaken lime brust; in condition of current market price of pyrite ore, the sintering process fixing free CaO with sulfur in pyrite ore is economically feasible.

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Tian, Jiao, and Qinghai Guo. "Thermal Decomposition of Hydrocalumite over a Temperature Range of 400–1500°C and Its Structure Reconstruction in Water." Journal of Chemistry 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/454098.

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The thermal decomposition process and structure memory effect of hydrocalumite were investigated systematically for the first time over a wide temperature range of 400–1500°C. The calcined hydrocalumite samples and their rehydrated products were characterized by XRD, FT-IR, and SEM-EDX. The results show that the calcination products at temperatures ranging from 500 to 900°C are basically mayenite and lime, while one of the final products obtained by calcination at and above 1000°C is probably tricalcium aluminate (Ca3Al2O6). For the hydrocalumite samples calcined at temperatures below 1000°C, their lamellar structure can be completely recovered in deionized water at room temperature. However, the further increase of calcination temperature could impair the regeneration ability of hydrocalumite via contact with water. Upon calcination of hydrocalumite at 1000–1500°C followed by reaction with water, a stable compound tricalcium aluminate hexahydrate (Ca3Al2O6·6H2O) was produced, which is the reason why less hydrocalumite could be regenerated.

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Scala, Fabrizio, Riccardo Chirone, Paola Meloni, Gianfranco Carcangiu, Marco Manca, Guido Mulas, and Aldo Mulas. "Fluidized bed desulfurization using lime obtained after slow calcination of limestone particles." Fuel 114 (December 2013): 99–105. http://dx.doi.org/10.1016/j.fuel.2012.11.072.

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Zhou, Longfei, Mifeng Gou, and Shuqiong Luo. "Hydration kinetics of a calcination activated bauxite tailings-lime-gypsum ternary system." Journal of Building Engineering 38 (June 2021): 102189. http://dx.doi.org/10.1016/j.jobe.2021.102189.

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Manocha, Sanjeev, and François Ponchon. "Management of Lime in Steel." Metals 8, no. 9 (August 31, 2018): 686. http://dx.doi.org/10.3390/met8090686.

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The EU28 total lime demand in 2017 was estimated at about 20 million tons, out of which about 40% are consumed in the iron and steel industry. Steel remains the major consumer after environment and construction. The lime industry is quite mature and consolidated in developed countries, with enough reserves and production to serve regional markets while being fragmented in developing nations where steel producers rely on local sourcing. There is relatively very little trade for lime worldwide. Lime has a critical role at different steps of the steelmaking process, and especially to make a good slag facilitating the removal of sulphur and phosphorus, and for providing a safer platform to withstand high intensity arc plasma in the electric arc furnace (EAF), and violent reactions in the basic oxygen furnace (BOF). Lime quality and quantity has a direct effect on slag quality, which affects metallurgical results, refractory life, liquid metal yield, and productivity, and therefore the total cost of the steel production. In this paper, we present the importance of careful selection in the limestone and calcination process, which influences critical lime quality characteristics. We shall further elaborate on the impact of lime characteristics in the optimization of the steelmaking process, metallurgical benefits, overall cost impact, potential savings, and environmental benefits.

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Liu, Yong Zhou, Ke Gao, Hao Jie Zhang, and Hui Qiang Zhu. "Study on the Active Excitation of Gangue as Grouting Material." Advanced Materials Research 1049-1050 (October 2014): 456–59. http://dx.doi.org/10.4028/www.scientific.net/amr.1049-1050.456.

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In this paper, three methods are adopted to excite the activation of gangue: low temperature calcination, milling, and chemistry compound. Using orthogonal design experimental method makes sure the optimum formulation of gangue-lime-sulfate basic system. The study of cement-gangue grouting material shows that mechanical properties and working performance are significantly improved. Significance of widespread use in the future is positive.

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TAHER, M., A. EL-SAYED, O. FARGHALY, and M. SHATAT. "PHYSICOCHEMICAL PROPERTIES OF METAKAOLIN-LIME PASTES AT DIFFERENT CALCINATION TEMPERATURES OF KAOLINITE CLAY." Al-Azhar Bulletin of Science 19, Issue A-2 (December 1, 2008): 1–17. http://dx.doi.org/10.21608/absb.2008.10505.

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Yang, Yuehan, Li Wang, Dehong Xia, Zeyi Jiang, Binfan Jiang, and Peikun Zhang. "Novel Lime Calcination System for CO2 Capture and Its Thermal–Mass Balance Analysis." ACS Omega 5, no. 42 (October 16, 2020): 27413–24. http://dx.doi.org/10.1021/acsomega.0c03850.

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Hua, Lim Hong, Fei Ling Pua, Rohaya Othman, Taufiq Yap Yun Hin, and Sharifah Nabihah. "Synthesis of Carbide Lime Derived Strong Base Catalyst for Biodiesel Production." Solid State Phenomena 317 (May 2021): 251–56. http://dx.doi.org/10.4028/www.scientific.net/ssp.317.251.

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Carbide lime is a result of acetylene production. Carbide lime made out of calcium hydroxide with minor amount of calcium carbonate. In this study, carbide lime was used as the raw material to synthesize a new base catalyst with high base strength. A strong base catalyst was prepared through calcination and impregnation with potassium fluoride. The structure and morphology of catalyst were investigated by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM) The base strength was determined by Hammett Indicator test, temperature-programmed desorption of carbon dioxide (TPD-CO2). The surface area of the catalyst was determined by Brunauer-Emmet-Teller isotherm (BET). The catalytic performance was examined through transesterification reaction. Fatty acid methyl ester (FAME) was successfully synthesized with the presence of carbide lime derived catalyst. The highest biodiesel conversion rate for sunflower oil was 95.83% with 6 wt% of catalyst loading while palm oil was 88.07% with 3 wt% of catalyst loading. The presence of the ester functional group was determined by Fourier Transform Infrared Spectroscopy (FTIR) analysis.

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Zhao, Qi Gang, Zuo Ren Nie, Hong Liu, Su Ping Cui, and Ya Li Wang. "Utilization of Municipal Sludge in the Calcination of Cement Clinker." Materials Science Forum 814 (March 2015): 546–51. http://dx.doi.org/10.4028/www.scientific.net/msf.814.546.

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Using the sludge of sewage treatment plant to calcine cement clinker is a new method and is confirmed on the international to utilize city sludge recycling and harmlessly. In this work the test of the raw material burnability, cement clinker mineral composition and petrographic analysis were used to study microscopic characteristics of clinker, to analysis of the effect of sludge performance of cement clinker calcination. It was found that when sludge were as a raw material for calcining cement clinker, best city sludge content was around 15% ~ 20%. With an improvement of lime saturation coefficient, the burnability of raw material declined. The mineral composition of sludge clinker was the same as that of the conventional Portland clinker, while mineral structure and morphology of the sludge clinker were better.

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Bal Krishna, K. C., Mohamed R. Niaz, Dipok C. Sarker, and Troy Jansen. "Phosphorous removal from aqueous solution can be enhanced through the calcination of lime sludge." Journal of Environmental Management 200 (September 2017): 359–65. http://dx.doi.org/10.1016/j.jenvman.2017.06.003.

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Erans, María, Theodor Beisheim, Vasilije Manovic, Michal Jeremias, Kumar Patchigolla, Heiko Dieter, Lunbo Duan, and Edward J. Anthony. "Effect of SO2and steam on CO2capture performance of biomass-templated calcium aluminate pellets." Faraday Discussions 192 (2016): 97–111. http://dx.doi.org/10.1039/c6fd00027d.

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Four types of synthetic sorbents were developed for high-temperature post-combustion calcium looping CO₂capture using Longcal limestone. Pellets were prepared with: lime and cement (LC); lime and flour (LF); lime, cement and flour (LCF); and lime, cement and flour doped with seawater (LCFSW). Flour was used as a templating material. All samples underwent 20 cycles in a TGA under two different calcination conditions. Moreover, the prepared sorbents were tested for 10 carbonation/calcination cycles in a 68 mm-internal-diameter bubbling fluidized bed (BFB) in three environments: with no sulphur and no steam; in the presence of sulphur; and with steam. When compared to limestone, all the synthetic sorbents exhibited enhanced CO₂capture performance in the BFB experiments, with the exception of the sample doped with seawater. In the BFB tests, the addition of cement binder during the pelletisation process resulted in the increase of CO₂capture capacity from 0.08 g CO₂per g sorbent (LF) to 0.15 g CO₂per g sorbent (LCF) by the 10^thcycle. The CO₂uptake in the presence of SO₂dramatically declined by the 10^thcycle; for example, from 0.22 g CO₂per g sorbent to 0.05 g CO₂per g sorbent in the case of the untemplated material (LC). However, as expected all samples showed improved performance in the presence of steam, and the decay of reactivity during the cycles was less pronounced. Nevertheless, in the BFB environment, the templated pellets showed poorer CO₂capture performance. This is presumably because of material loss due to attrition under the FB conditions. By contrast, the templated materials performed better than untemplated materials under TGA conditions. This indicates that the reduction of attrition is critical when employing templated materials in realistic systems with FB reactors.

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Mohd Darus, D., H. Aimi Noorliyana, R. Azmi, and H. Kamarudin. "Reactions of Limestone on the Slaking Process under Different Conditions of Parameters." Materials Science Forum 819 (June 2015): 393–98. http://dx.doi.org/10.4028/www.scientific.net/msf.819.393.

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The reaction of limestone in the slaking process has been studied under different conditions of parameters such as calcination times, soaking times and particle sizes. The reactivity of quicklime was determined by recording temperature rise and the rate of temperature rise during the slaking process. The obtained ‘milk of lime’ is characterized using instrumental measurements such as X-ray fluorescence (XRF) to identify the chemical composition that exists in the sample. In this paper, the quicklime used during slaking test indicates the differential of temperature pattern which influences by quicklime particle sizes, calcination temperatures and soaking times. Results indicate that the optimum and efficient distribution of heat transfer and thermal decomposition onto quicklime can be obtained by calcining at 1100 °C with 60 minutes of soaking time samples which produced a highly porous structure towards higher reactivity of quicklime.

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DA SILVA, Deoclécio Junior Cardoso, Nattan Roberto CAETANO, Antonio Vanderlei DOS SANTOS, Leoni Pentiado GODOY, and Marcos Antônio KLUNK. "REUSE RESIDUAL SAND CASTING FOR PRODUCTION OF CONCRETE BLOCKS." SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 28, no. 29 (December 20, 2020): 55–65. http://dx.doi.org/10.48141/sbjchem.v28.n29.2020.07_dasilva_pgs_55_65.pdf.

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The ore beneficiation process uses little technology, but mining companies have high economic performance. As an energy source, firewood plays a fundamental role due to its simple storage, low cost, great availability of forests, and lack of processing. Thus, the present work aims to analyze the consumption of firewood as fuel and possible improvements in the process for the production of lime in terms of harnessing raw materials and costs. Calcium oxide is obtained from the thermal decomposition of calcium and magnesium carbonates obtained from dolomitic deposits of limestone (CaCO3 : CaMgCO3). After CaO extraction, it is subjected to a calcination process, removing carbon dioxide (CO2) in ovens that work at temperatures between 900 and 1200°C. The source of energy applied to the calcination furnaces in the analyzed area is wood. The wood has a calorific value between 2,250 and 2,700 Kcal/Kg, but the moisture content responsible for the thermal variation must be considered. The firewood burning process was carried out in a ravine type oven where the temperature at which operators are exposed to heat was evaluated. The results indicated that the cooking time dropped by 20% as the amount of wood is fed into the oven. This increase represents a significant gain in lime production, thus leading to a higher profit for the company.

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Acke, Filip, and Itai Panas. "Activation energy for calcination of lime stone by means of a temperature programmed reaction technique." Thermochimica Acta 303, no. 2 (October 1997): 151–54. http://dx.doi.org/10.1016/s0040-6031(97)00257-8.

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Yakornov, S. A., A. M. Panshin, P. I. Grudinsky, V. G. Dyubanov, L. I. Leontiev, P. A. Kozlov, and D. A. Ivakin. "Method of Electric Arc Furnace Dust Processing by Calcination with Lime with Following Alkaline Leaching." Russian Metallurgy (Metally) 2018, no. 13 (December 2018): 1282–87. http://dx.doi.org/10.1134/s0036029518130268.

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Hago, A. W., and Amer Ali Al-Rawas. "An investigation into the Traditional Method of Production of Omani Sarooj." Sultan Qaboos University Journal for Science [SQUJS] 4 (December 1, 1999): 35. http://dx.doi.org/10.24200/squjs.vol4iss0pp35-43.

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In the past, sarooj had been used as the basic cementing material with which the A flaj system (the irrigation system used in Oman) was built. Worldwide, materials like sarooj existed and were known for their good impermeability and long durability. For this reason it was extensively used in hydraulic structures. Even in this century and with the ready availability of Portland cements, special plants were erected to produce materials like sarooj for major dams in the world. In the process of hydration In sarooj-lime mixes or in sarooj-cement mixes free lime is released which causes distress through the expansion of the mortar if allowed to accumulate. If free lime is stabilized within the structure of the mortar. it imparts additional strength and durability to it. The mortar becomes less permeable to water, which increases its resistance to wearhering. The stabilization is possible through the presence of a reactive silica/alumina in the mix so that it reacts with the free lime to form calcium silicates/aluminates. The properties of sarooj depend largely on the type of the raw material and the calcination parameters. This paper describes this material, its method of production and uses, and highlights research currently conducted to improve its properties.

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Leontakianakos, G., I. Baziotis, V. N. Stathopoulos, Z. Kypritidou, L. Profitis, E. Chatzitheodoridis, and S. Tsimas. "Influence of natural water composition on reactivity of quicklime derived from Ca-rich and Mg-rich limestone: implications for sustainability of lime manufacturing through geochemical modeling." RSC Advances 6, no. 70 (2016): 65799–807. http://dx.doi.org/10.1039/c6ra11346j.

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Li, Bingrong, Yaowu Wei, Nan Li, Tao Zhang, and Jinhu Wang. "Effect of Al(OH)3 and La2O3 on the sintering behavior of CaO granules via CaCo3 decomposition." Science of Sintering 52, no. 2 (2020): 195–206. http://dx.doi.org/10.2298/sos2002195l.

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Hydration resistance of CaO aggregates is the key to the successful application of lime-based refractories. Granulation technology on limestone with additives and one step calcination method was used in this study to investigate the effects of Al(OH)3 and La2O3 on the sintering behavior and the hydration resistance of CaO granules. The result showed that the hydration resistance of CaO granules was improved significantly by adding Al(OH)3 and La2O3. The shell of sintered CaO granules was relatively dense after calcination and the specific surface area of CaO granules decreased from 7.5?10-2 m2/g to 1.2?10-2 m2/g. The average pore size of CaO granular was decreased from 3.54 ?m to 0.83 ?m due to the liquid phase sintering when Al(OH)3 additive was used. La2O3 promoted the densification of CaO compact by the ion substitution and solution with CaO. La3+ approached into CaO lattices, which enlarged the vacancy concentration of Ca2+ and accelerated the diffusion of Ca2+.

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Xu, Yue, Jian Xi Li, and Li Li Kan. "Investigation on a New Hydraulic Cementitious Binder Made from Phosphogypsum." Advanced Materials Research 864-867 (December 2013): 1923–28. http://dx.doi.org/10.4028/www.scientific.net/amr.864-867.1923.

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A new kind of high strength cementitious material is made from phosphogypsum (PG), active carbon and fly-ash. Through the orthogonal research, it was showed that the calcination temperature, retention time, dosage of active carbon and fly ash on the compressive strength of cementitious binder are the most important. The result also showed that, in the conditions of temperature 1200°C, time retention 30 min, dosage of active carbon 10%, dosage of fly ash 5%, the compressive strength of the cementitious material for 3d and 28d could reach to 46.35MPa and 92.70MPa, the content of sulfur trioxide was 11.60% accordingly. A lot of active mineral materials, such as dicalcium silicate, tricalcium silicate, tricalcium aluminate were formed in the calcination. The C-S-H gel, calcium hydroxide and ettringite were found in 3d and 28d hydrates. It is found that the lime saturation ratio and silica modulus need to be control between 0.40~0.65 and 4~8 in order to produce high strength cementitious material.

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Malnieks, Kaspars, Gundars Mezinskis, and Ilona Pavlovska. "Effect of Different Dip-Coating Techniques on TiO₂ Thin Film Properties." Key Engineering Materials 721 (December 2016): 128–32. http://dx.doi.org/10.4028/www.scientific.net/kem.721.128.

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TiO2 three-layer sol-gel films have been deposited on soda-lime silicate glass slides and dried in two different ways to study the effect of drying on thin film structure. The structural properties, surface topography and photocatalytic activity of the films were studied by X-ray diffraction, atomic force microscopy, and by analysing photocatalytic degradation of methyl orange, respectively. The titanium oxide sol-gel layers on glass slides dried at 20 °C before the deposition of next layers after final calcination at 500 °C resulted in a nanorod array film with good photocatalytic activity.

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Tantawy, M. A., M. R. Shatat, A. M. El-Roudi, M. A. Taher, and M. Abd-El-Hamed. "Low Temperature Synthesis of Belite Cement Based on Silica Fume and Lime." International Scholarly Research Notices 2014 (October 29, 2014): 1–10. http://dx.doi.org/10.1155/2014/873215.

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This paper describes the low temperature synthesis of belite (β-C2S) from silica fume. Mixtures of lime, BaCl2, and silica fume with the ratio of (Ca + Ba)/Si = 2 were hydrothermally treated in stainless steel capsule at 110–150°C for 2–5 hours, calcined at 600–700°C for 3 hours, and analyzed by FTIR, XRD, TGA/DTA, and SEM techniques. Dicalcium silicate hydrate (hillebrandite) was prepared by hydrothermal treatment of lime/silica fume mixtures with (Ca + Ba)/Si = 2 at 110°C for 5 hours. Hillebrandite partially dehydrates in two steps at 422 and 508°C and transforms to γ-C2S at 734°C which in turn transforms to α′-C2S at 955°C which in turn transforms to β-C2S when cooled. In presence of Ba2+ ions, β-C2S could be stabilized with minor transformation to γ-C2S. Mixture of silica fume, lime, and BaCl2 with the ratio of (Ca + Ba)/Si = 2 was successfully utilized for synthesis of β-C2S by hydrothermal treatment at 110°C for 5 hours followed by calcination of the product at 700°C for 3 hours.

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Zaman, T., Mst S. Mostari, Md A. Al Mahmood, and Md S. Rahman. "Evolution and characterization of eggshell as a potential candidate of raw material." Cerâmica 64, no. 370 (June 2018): 236–41. http://dx.doi.org/10.1590/0366-69132018643702349.

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Abstract Characterization of both uncalcined and calcined eggshells was done in this work. Raw eggshells turned out as a good source of calcite phase. Calcined eggshells had a mixture of lime and portlandite phase. A significant impact of calcination temperature on the percentage of generated phases was observed. Qualitative as well as semi-quantitative phase analysis, morphological characterization and physical property estimation was done for the produced powder. The influence of synthesized raw material on soil stabilization and biomaterial formation was further assessed. The eggshell turned out as a potential source of raw material for various sectors.

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Kavosh, Masoud, Kumar Patchigolla, Edward J. Anthony, and John E. Oakey. "Carbonation performance of lime for cyclic CO 2 capture following limestone calcination in steam/CO 2 atmosphere." Applied Energy 131 (October 2014): 499–507. http://dx.doi.org/10.1016/j.apenergy.2014.05.020.

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Ebneyamini, Arian, Zezhong John Li, Jun Young Kim, John R. Grace, C. Jim Lim, and Naoko Ellis. "Effect of calcination temperature and extent on the multi-cycle CO2 carrying capacity of lime-based sorbents." Journal of CO2 Utilization 49 (July 2021): 101546. http://dx.doi.org/10.1016/j.jcou.2021.101546.

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47

Lamezon de Pádua, Paula G., Túlio H. Panzera, Roberto B. Figueiredo, A. M. Gomes, and Maria T. Paulino Aguilar. "Investigations on the Pozzolanic Effect of Sugar Cane Bagasse Ashes Used in Cementitious Composites." Open Construction and Building Technology Journal 10, no. 1 (June 28, 2016): 395–405. http://dx.doi.org/10.2174/1874836801610010395.

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Brazil is a major producer of alcohol from sugar cane, a fuel with low environmental impact. The production of alcohol generates a large amount of bagasse, the biggest waste of Brazilian agriculture. This bagasse is usually burned for energy production providing nearly 3% of residual ashes. The potential use of these ashes like mineral admixture of cementitious composites depends on calcination conditions. The present work identifies the physical and chemical characteristics of ashes from the furnace exhauster, obtained in an industry located at southeast region of Brazil. The ashes were obtained from bagasse of sugar cane harvest in two different seasons. Chemical composition analysis, X-ray diffraction, grain size distribution, loss on ignition, thermogravimetry analysis (TGA), differential scanning calorimetry (DSC), specific surface measurements (BET) and Fourier transform infrared spectroscopy (FTIR) tests were used to characterize the ashes. The pozzolanic activity was estimated by pozzolanic activity index tests with cement and lime, by the modified Chapelle test, electrical conductivity in lime solution tests, TGA and FTIR. The ashes presented different chemical compositions and degree of amorphicity. The ashes with a higher content of silica, the lower organic material content and high degree of crystallinity (1st harvest), for the same size, have higher pozzolanic on electrical conductivity in lime solution tests than the ashes with lower silica content and higher amorphicity (2nd harvest). However, the results of differential scanning calorimetry (DSC) and modified Chapelle method would indicate the pozzolanicity of the ashes of the 2nd harvest. The results of pozzolanic activity index (with cement or lime) indicated the ashes were not pozzolanic.

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Munawaroh, Fatimatul, Laila Khamsatul Muharrami, Triwikantoro Triwikantoro, and Zaenal Arifin. "CALCIUM OXIDE CHARACTERISTICS PREPARED FROM AMBUNTEN’S CALCINED LIMESTONE." Jurnal Pena Sains 5, no. 1 (May 2, 2018): 65. http://dx.doi.org/10.21107/jps.v5i1.3836.

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<pre>Calcium oxide (CaO) and calcium carbonate (CaCO3) are widely used in industry. CaO and CaCO3 can be synthesized or derived from limestone. The purpose of this study to determine the characteristics of CaO calcined limestone from Ambunten Sumenep. Lime in calcined at 850 ° C for 6 hours. Characterization of X-ray fluorescence (XRF) was conducted to determine the chemical composition of limestone, X-ray diffraction test (XRD) to find the lime crystalline phase and FTIR test to determine the absorption of wave number. XRF test results showed that the limestone chemical composition consisted of Ca of 95.37% as the dominant element, Mg of 4.1%, Fe 0.17% and Y by 0.39%. The XRD test results showed that the limestone crystal phase is ankerite (Ca [Fe, Mg] [CO3] 2) and after the calcined phase calcination is vaterite (Ca [OH] 2), calcite (CaO) and calcite (CaCO3). While the FTIR test results show that the CaO spectra are seen at 3741.24, 1417.12 and 874.14 cm</pre><sup>-1</sup><pre>.</pre>

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Paz, Y., and A. Heller. "Photo-oxidatively self-cleaning transparent titanium dioxide films on soda lime glass: The deleterious effect of sodium contamination and its prevention." Journal of Materials Research 12, no. 10 (October 1997): 2759–66. http://dx.doi.org/10.1557/jmr.1997.0367.

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In the context of photocatalytically self-cleaning windows and windshields, clear, abrasion resistant, thin (60 ± 10 nm) photocatalytic films of TiO2 were formed by a sol-gel process on (a) soda lime glass, (b) the proton-exchanged surface of soda lime glass, and (c) fused silica. The hypothesis that diffusion of sodium oxide from the soda lime glass into the titanium dioxide layer during the calcination step causes the lower photoefficiency in films on glass was tested and proven. At high concentration sodium prevented formation of the photoactive anatase phase and, at low concentration, introduced surface and bulk recombination centers. Sodium transport was efficiently blocked by a thin layer at the interface of proton-exchanged (“hydrogen”) glass and nascent TiO2, formed at 400 °C of a poly(titanyl acetylacetonate) TiO2 precursor. The sodium transport blocking layer did not form and the highly photocatalytic film was not obtained when the TiO2-precursor film was applied to glass that was not proton exchanged. Furthermore, only a much less effective sodium transport blocking layer was formed on glass that was proton-exchanged, but was calcined at 400 °C prior to application of the TiO2 precursor layer, showing that the sodium depleted glass surface, by itself, was a less effective barrier against sodium transport than the interfacial product of hydrogen glass and the TiO2 precursor.

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Yu, Huogen, Jia Guo Yu, Bei Cheng, C. H. Ao, and S. C. Lee. "Effects of Substrates on the Composition and Microstructure of TiO₂ Thin Films Prepared by the LPD Method." Key Engineering Materials 280-283 (February 2007): 795–800. http://dx.doi.org/10.4028/www.scientific.net/kem.280-283.795.

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TiO2 thin films were prepared on soda lime glass, fused quartz and stainless steel substrates by liquid phase deposition (LPD) method from a (NH4)2TiF6 aqueous solution upon the addition of boric acid (H3BO3), and then calcined at 500oC for 2 h. The prepared films were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). It was found that the substrates obviously influenced the element composition and microstructure of TiO2 thin films. Except Ti, O and a small amount of F and N elements, which came from the precursor solution, some Si (or Fe) element in the thin films deposited on soda lime glass and quartz substrates (or on stainless steel substrate) was confirmed. The Si (or Fe) element in the thin films could be attributed to two sources. One was from the SiF6 2- ions (or FeF6 2- ions) formed by a reaction between the treatment solution and soda lime glass or quartz (or stainless steel) substrates. The other was attributed to the diffusion of Si (or Fe) from the surface of substrates into the TiO2 thin films after calcination at 500oC. The Si (or Fe) element in the TiO2 thin films could behave as a dopant and resulted in the formation of composite SiO2/TiO2 (or Fe2O3/TiO2) thin films on the substrates.

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Journal articles on the topic 'Calcination of hydrailic lime'

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