DOCSLIB.ORG

May 16, 1967 W. F. WALDECK 3,320,0 6 METHOD of PREPARING CALCITE and the PRODUCT THEREOF Filed Feb

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
May 16, 1967 W. F. WALDECK 3,320,0 6 METHOD of PREPARING CALCITE and the PRODUCT THEREOF Filed Feb May 16, 1967 w. F. WALDECK 3,320,0 6 METHOD OF PREPARING CALCITE AND THE PRODUCT THEREOF Filed Feb. 20, 1964 5 Sheets-Sheet 1 PRIOR ART (.7, I____: ONE MICRON May 15, 1967 w. F. wALDEcK “ 3,320,026 METHOD OF PREPARING CALCITE vAND THE PRODUCT THEREOF Filed Feb. 20, 1964 5 Sheets-Sheet 2 5%, w M? l__:__.| ONE MICRON May 16, 1967 w. F. WALDECK 3,320,026 METHOD OF PREPARING CALCITE AND THE PRODUCT THEREOF Filed Feb. 20, 1964 5 Sheets-Sheet 5 O.l MICRON Fig.6 3,320,026 United States Patent nice Patented May 16, 1967 1 2 complete reaction to product substantially free of other 3,320,026 crystalline forms. METHDD 0F PREPARING CALCITE AND THE PRODUCT THEREOF Carbonatation may be conducted in standard gas-liquid William F. Waldeclr, Milford, N.J., assignor to Chas. contacting equipment. For example, an agitated tank P?zer & Co., Inc., New York, N.Y., a corporation of may be employed, carbon dioxide-containing gas being Delaware suitably injected beneath the agitator for thorough dis Filed Feb. 20, 1964, Ser. No. 346,349 persion throughout the reaction mixture. A typical plant 16 Claims. (Cl. 23-66) scale precipitation may require one or two hours, under which circumstances it will usually be appropriate to This invention is concerned with calcium carbonate, 10 maintain the temperature below 20° C. for about 10 or and more particularly with a calcite of novel crystal 15 minutes, by recirculating some of the slurry through habit, and processes for its preparation and use. a cooler. Cooling will usually be curtailed as crystalli Calcium carbonate can be precipitated in any of three zation proceeds, so that the temperature will begin to rise. isomorphons crystal groups, the calcite, aragonite and When carbonate formation is about half complete the vaterite groups. When obtained in calcite form, calcium cooling can usually be halted entirely. carbonate ordinarily assumes either a rhombohedral or a The carbon dioxide injected into the reaction mixture scalenohedral habit. Now, however, an especially valu may be pure, i.e. free of other diluent gases, but this is able calcite of novel habit has been obtained, differing by no means necessary. Flue gases containing about 12 from all known naturally occurring minerals or previ volume percent or more of carbon dioxide in admixture ously reported synthetic products. X-ray analysis estab 20 with non-reactive gaseous diluent are suitable, although lishes the fact that the new calcium carbonate is of the for more rapid absorption it will be preferable to employ calcite group, but the distinctive nature of its crystalline a somewhat richer source, such as the gases from lime habit will be clear from the accompanying illustrations, burning, which contain about 20-40% carbon dioxide. which are photographic reproductions of highly magni At the conclusion of the process, the calcite crystals ?ed electro micrographs. may be recovered from the aqueous suspension in dis FIG. 1 depicts prior art aragonite. crete form. Any coarse grit or un-reacted lime present FIG. 2 shows prior art vaterite. are best eliminated by an initial screening of the reaction In FIG. 3 is shown the prior art scalenohedral form slurry through a 325 mesh U.S. sieve screen, after which of calcite. the product is collected from the screened liquor by ?l FIG. 4 shows the prior art rhombohedral form of tration or other conventional procedure. The product calcite. may upon drying, be subjected to a single pass through FIG. 5 is an electron micrograph of the new stubby a hammer mill, to disintegrate any lumps and insure a prismatic calcite crystals of the present invention. uniform, free-?owing powder composed of discrete cal FIG. 6 represents a still further magni?ed view of these cite crystals. new crystals. ' It has been stated that at least 50 weight percent of The novel calcite is produced by the introduction of the calcium hydroxide particles employed in the process carbon dioxide into an aqueous calcium hydroxide sus of this invention must have a diameter above about 10 pension (“carbonatation”). Calcium carbonate has been microns. Electron micrographs suggest that calcium hy produced by such processes in the past, but the products droxide consists of aggregate clusters of fundamental obtained were of the conventional types mentioned. The 40 crystals about 0.01 micron in size, and the relatively critical process conditions required to produce the stubby large particles employed in the new process are believed prismatic calcite crystals are newly discovered and form to be such aggregate clusters. a part of the present invention. Since the lime particle diameter is a somewhat incon In the new process, carbon dioxide is introduced into venient value to measure in practice, a process criterion an aqueous suspension of coarse calcium hydroxide (at based on settling rate has been developed, In accordance least about 50 weight percent of the hydroxide consisting with this standard, the particle size should be such that of particles coarser than 10 microns) while maintaining 1000 ml. of homogeneous water suspension at 65° C. the temperature below about 20° C. at least until calcite containing 150 grams of said particles exhibits a settled crystallization is in progress. Carbon dioxide introduc particle volume below about 960 ml. in a standard 1000 tion is then continued, and the temperature may be per~ - ml. graduated cylinder after 10 minutes’ standing. That mitted to rise, while calcite crystalliaztion continues to is to say, the interface between the clear supernatant wa substantial completion. ter and the cloudy suspension should lie below this limit. The initial temperature during calcite crystallization is Such a slurry is indeed a coarse suspension, in contrast critical. If carbon dioxide is introduced to the lime sus to so-called “milk of lime,” which typically exhibits a pension at a temperature substantially above 20° C. there settled volume of 990 ml. or more in the described test. is a strong tendency to precipitate scalenohedral calcite, The ?nely divided milks have been employed almost uni~ and at still higher temperatures, aragonite is obtained. versally in the past in general industrial practice, being Any temperature below 20° will be satisfactory, and ex favored because of their resemblance to true solutions in cellent results are obtained at 15-16". Once prismatic handling properties. calcite crystallization is in progress, however, the tem 60 Ordinarily, lime milks are prepared by slaking reac perature may be permitted to rise while crystallization tive lime with hot water, or with limited amounts of of the novel product continues. Apparently the initial water (with subsequent dilution if necessary), so that the crystallization insures massive inoculation of the slurry exothermic reaction produces a rather high temperature, with the desired crystal form, whereby this type continues ften 90-100“ C. The resulting products are entirely to appear even at the higher temperatures where scaleno 65 unsatisfactory in the process of the present invention. hedrons might otherwise be expected. Permitting the In order to produce a calcium hydroxide suspension of temperature to rise during crystallization is, in fact, often the requisite coarseness for the new process, the tempera desirable, to insure complete conversion of even the slow ture during slaking must never be permitted to exceed reacting, coarser calcium hydroxide particles. A maxi 70 65° C. It is therefore, of course, prudent to provide mum crystallization temperature in the range between ef?cient agitation during slaking, to avoid the possibility about 30 and 45° C. is particularly preferred, to insure of local overheating. ’ 3,820,026 A; The maximum temperature during slaking will natural the best commercial chalks, i.e., the rhombohedral cal ly vary with the initial water temperature, the quicklime: cites. This dramatic advantage is accompanied by a slake water ratio ‘and the reactivity of the quicklime. very considerable increase in printability, achieved at low (It can also be controlled, of course, by external cooling er calender pressure or with fewer than customary passes if desired.) Experience has shown that a slaking tem through the calender rolls. “Calgon T Demand,” a meas perature below 65° C. can be assured, and particularly ure of the quantity of this polyphosphate dispersant which good results obtained, by providing water at an initial is required to achieve minimum viscosity of a high solids temperature of no higher than 35° C. for the slaking chalk slurry, is also desirably low. Even in combination reaction; in addition, the quicklimezslake water ratio with conventional forms of calcite, the stubby prismatic should preferably not exceed that which will produce 10 product affords signi?cant advantages, provided at least about 20 grams calcium hydroxide per 100 ml. suspen about 50% by weight, and preferably 75—80% or more sion. Particularly desirable is a quicklime proportion to of the new product is present. produce a suspension containing from about 10 to 15 To reduce cost, paper-coating pigments are usually grams calcium hydroxide per 100 ml. suspension. clay-‘based, with chalk added primarily for whiteness. Very low quicklime proportions, i.e., those which pro Most commercial chalks are, in fact, incapable of provid duce a suspension containing less than about 10 grams ing the desired gloss and printability when employed calcium hydroxide per 100 ml., tend to be uneconomic. alone. While the new calcite overcomes these technical This disadvantage may be overcome by subsequently in disadvantages, the economic factor will often dictate .its troducing additional lime, at least 50 weight percent of use in combination with clay for many paper-coating ap which is coarser than 10 microns, so as to raise the total plications. Inorganic clay-based pigments containing at calcium content to a level equivalent to about 10-20 least 20% by weight of the stubby-prismatic calcite pro grams of calcium hydroxide per 100 ml.
Load more

Recommended publications
  • Municipal Solid Waste Incineration (MSWI) Ashes for Greener Concrete Master’S Project for the Master Program of Structural
    Municipal solid waste incineration (MSWI) ashes for greener concrete Master’s project for the Master Program of Structural Engineering and Building Technology ARNAUD GLIKSON SARA LÓPEZ MENÉNDEZ Department of Architecture and Civil Engineering Division of Building Technology Building Materials CHALMERS UNIVERSITY OF TECHNOLOGY Master’s Thesis ACEX30-19-97 Gothenburg, Sweden 2019 MASTER’S THESIS ACEX30-19-97 Municipal solid waste incineration (MSWI) ashes for greener concrete Master’s project for the Master Program of Structural Engineering and Building Technology ARNAUD GLIKSON SARA LÓPEZ MENÉNDEZ Department of Architecture and Civil Engineering Division of Building Technology Building Materials CHALMERS UNIVERSITY OF TECHNOLOGY Göteborg, Sweden 2019 Municipal solid waste incineration (MSWI) ashes for greener concrete Master’s project for the Master Program of Structural Engineering and Building Technology ARNAUD GLIKSON SARA LÓPEZ MENÉNDEZ © ARNAUD GLIKSON, SARA LÓPEZ MENÉNDEZ, 2019 Examensarbete ACEX30-19-97 Institutionen för arkitektur och samhällsbyggnadsteknik Chalmers tekniska högskola, 2019 Department of Architecture and Civil Engineering Division of Building Technology Building Materials Chalmers University of Technology SE-412 96 Göteborg Sweden Telephone: + 46 (0)31-772 1000 Department of Architecture and Civil Engineering Göteborg, Sweden, 2019 Municipal solid waste incineration (MSWI) ashes for greener concrete Master’s project for the Master Program of Structural Engineering and Building Technology ARNAUD GLIKSON SARA LÓPEZ MENÉNDEZ Department of Architecture and Civil Engineering Division of Building Technology Building Materials Chalmers University of Technology ABSTRACT Owing to the varying characteristics of municipal solid waste incineration (MSWI) ashes and the lack of harmonized standards and regulations, a substantial portion of MSWI ashes are simply used as landfilling cover at the present, which can be better utilized in the viewpoint of sustainability.
    [Show full text]
  • Opportunities for Geologic Carbon Sequestration in Washington State
    Opportunities for Geologic Carbon Sequestration in Washington State Contributors: Jacob R. Childers, Ryan W. Daniels, Leo F. MacLeod, Jonathan D. Rowe, and Chrisopher R. Walker Faculty Advisor: Juliet G. Crider Department of Earth and Space Sciences University of Washington, Seattle May 2020 ESS Special Topics Task Force Report 001 Preface and Acknowledgment This report is the product of reading, conversation, writing and revision by a group of undergraduate student authors during 10 weeks of March, April and May 2020. Our intent is to review the basic processes and state of current scientific understanding of geologic carbon sequestration relevant to Washington State. We would like to thank Dr. Thomas L. Doe (Golder Associates) for reading the final report and asking us challenging questions. i I. Introduction Anthropogenic emissions of greenhouse gasses like CO2 are raising global temperatures ​ ​ at an unprecedented rate. According to the most recent United Nations Intergovernmental Panel on Climate Change report, global emissions have caused ~1°C global warming above pre-industrial levels, with impacts such as rising sea level and changing weather patterns (IPCC 2018). The IPCC states that the current rate of emissions will lead to global warming of 1.5°C sometime between 2030 to 2052, and that temperature will continue to rise above that if emissions are not halted. They state that impacts of global warming, such as drought or extreme precipitation, will increase with a 1.5°C temperature increase. However, these effects will be less than the impacts of global temperature increase of beyond 2°C. The IPCC also projects that global sea level rise will be 0.1 m lower at 1.5°C warming than at 2°C warming, exposing 10 million fewer people to risks related to sea level rise.
    [Show full text]
  • BOOK of ABSTRACTS SCK•CEN-BA-53 13/Dja/P-23
    BOOK OF ABSTRACTS SCK•CEN-BA-53 13/Dja/P-23 3rd International Workshop Mechanisms and modelling of waste/cement interactions Ghent, 06-08 May 2013 SCK•CEN Boeretang 200 BE-2400 MOL Belgium http://www.sckcen.be BOOK OF ABSTRACTS SCK•CEN-BA-53 3rd International Workshop Mechanisms and modelling of waste/cement interactions Ghent, 06-08 May 2013 SCK•CEN, Boeretang 200, BE-2400 MOL, Belgium Contact: Diederik Jacques Tel: +32 14 33 32 09 E-mail: [email protected] Organising committee Workshop convenors Geert De Schutter, UGent, B Diederik Jacques, SCK•CEN, B Hans Meeussen, NRG, NL Hans van der Sloot, ECN, NL Tom van Gerven, KU Leuven, B Lian Wang, SCK•CEN, B International Steering Committee Urs Berner, PSI, CH Céline Cau Dit Coumes, CEA, F Frederic Glasser, Aberdeen University, UK Bernd Grambow, SUBATECH, F James Kirkpatrick, Michigan State University, USA Barbara Lothenbach, Empa, CH André Nonat, Univ. Bourgogne, F © SCK•CEN Studiecentrum voor Kernenergie Centre d’Etude de l’Energie Nucléaire Boeretang 200 BE-2400 MOL Belgium http://www.sckcen.be Status: Unclassified RESTRICTED All property rights and copyright are reserved. Any communication or reproduction of this document, and any communication or use of its content without explicit authorization is prohibited. Any infringement to this rule is illegal and entitles to claim damages from the infringer, without prejudice to any other right in case of granting a patent or registration in the field of intellectual property. Copyright of the individual abstracts and papers rests with the authors and the SCK•CEN takes no responsability on behalf of their content and their further use.
    [Show full text]
  • Ph Sensors in Sugar Refining
    pH sensors in sugar refining Use of Hamilton’s Polilyte Plus in raw sugar juice carbonatation Industry: Sugar production Application: Carbonatation of raw juice Sugar Washing Beets Slicing Hamilton products: Polilyte Plus Pellets Slices Drying Water Extraction Scraps Pelletation Crystalline sugar is the major sweetening agent in many coun- Lime tries. Therefore, a reliable supply of quality sugar is essential for Raw Juice CaCO3 many people. Lime Lime milk Ca(OH) Liming With an average content of 20%, sugar beets are a major burning 2 source of the sugar sucrose worldwide. Purification of sucrose from the beets is conducted in refineries through a multi-step Carbon Carbonatation Washing dioxide CO process where efficiency is essential to produce quality product 2 1 water with the lowest possible cost. Lime + Water Washing Freshly harvested beets are cleaned and sliced at the refinery, impurities g where the sucrose is extracted by hot water. The resulting raw Cleanin juice is purified in the carbonatation process, producing thin Carbon Filtration Filter cake dioxide CO2 juice. Through evaporation, thin juice is then concentrated into Juice thick juice and fed into crystallizers to produce the final crystal- Carbonatation lized sugar product. 2 Carbonatation and pH Melasse Lime + Raw juice contains about 99% of the sugar from the beets, Filtration impurities but also several organic and inorganic non-sugar compounds. They can be removed by precipitation with burned lime (cal- Thin Juice cium oxide) and carbon dioxide. Steam Thickening Steam In the carbonatation process, first burnt lime is added to the raw juice. A loose precipitate of calcium hydroxide and non- Thick Juice sugar compounds forms and carbon dioxide gas is added to the raw juice.
    [Show full text]
  • Carbonation of Alkaline Paper Mill Waste to Reduce CO2 Greenhouse Gas Emissions Into the Atmosphere R
    Carbonation of alkaline paper mill waste to reduce CO2 greenhouse gas emissions into the atmosphere R. Perez-Lopez, G. Montes-Hernandez, J.-M. Nieto, F. Renard, L. Charlet To cite this version: R. Perez-Lopez, G. Montes-Hernandez, J.-M. Nieto, F. Renard, L. Charlet. Carbonation of alkaline paper mill waste to reduce CO2 greenhouse gas emissions into the atmosphere. Applied Geochemistry, Elsevier, 2008, 23 (8), pp.2292 à 2300. 10.1016/j.apgeochem.2008.04.016. insu-00351929 HAL Id: insu-00351929 https://hal-insu.archives-ouvertes.fr/insu-00351929 Submitted on 12 Jan 2009 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. 1 Carbonation of alkaline paper mill waste to reduce CO2 greenhouse gas 2 emissions into the atmosphere 3 4 R. Pérez-López∗, a,b, G. Montes-Hernandez a, J.M. Nieto b, F. Renard c,d, L. Charlet a 5 6 a LGIT, CNRS-OSUG-UJF, Université Joseph Fourier, Grenoble I, Maison des Géosciences, BP 53, 7 38041 Grenoble Cedex, France 8 b Department of Geology, University of Huelva, Campus ‘El Carmen’, 21071, Huelva, Spain 9 c LGCA, CNRS-OSUG-UJF, Université Joseph Fourier, Grenoble I, Maison des Géosciences, BP 53, 10 38041 Grenoble Cedex, France 11 d Physics of Geological Processes, University of Oslo, Norway 12 13 14 To be submitted to Applied Geochemistry on December 18th, 2007 15 ∗ Corresponding author.
    [Show full text]
  • CO2 Sequestration in the Production of Portland Cement Mortars with Calcium Carbonate Additions
    nanomaterials Article CO2 Sequestration in the Production of Portland Cement Mortars with Calcium Carbonate Additions Marius-George Parvan, Georgeta Voicu *, Alina-Ioana Badanoiu, Adrian-Ionut Nicoara and Eugeniu Vasile Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Material Science, University POLITEHNICA of Bucharest, 1-7 Gh. Polizu Street, District 1, RO-011061 Bucharest, Romania; [email protected] (M.-G.P.); [email protected] (A.-I.B.); [email protected] (A.-I.N.); [email protected] (E.V.) * Correspondence: [email protected] Abstract: The paper presents the obtention and characterization of Portland cement mortars with limestone filler and nano-calcite additions. The nano-calcite was obtained by the injection of CO2 in a nano-Ca(OH)2 suspension. The resulted nano-CaCO3 presents different morphologies, i.e., polyhedral and needle like crystals, depending on the initial Ca(OH)2 concentration of the sus- pension. The formation of calcium carbonate in suspensions was confirmed by X-ray diffraction (XRD), complex thermal analysis (DTA-TG), scanning electron microscopy (SEM) and transmis- sion electron microscopy (TEM and HRTEM). This demonstrates the viability of this method to successfully sequestrate CO2 in cement-based materials. The use of this type of nano-CaCO3 in mortar formulations based on PC does not adversely modify the initial and final setting time of cements; for all studied pastes, the setting time decreases with increase of calcium carbonate content (irrespective of the particle size). Specific hydrated phases formed by Portland cement hydration Citation: Parvan, M.-G.; Voicu, G.; Badanoiu, A.-I.; Nicoara, A.-I.; Vasile, were observed in all mortars, with limestone filler additions or nano-CaCO3, irrespective of curing E.
    [Show full text]
  • Investigation Into the Filterability of Raw Sugars from Different Geographical Regions of the World
    International Journal of Computational and Theoretical Chemistry 2017; 5(6): 53-58 http://www.sciencepublishinggroup.com/j/ijctc doi: 10.11648/j.ijctc.20170506.11 ISSN: 2376-7286 (Print); ISSN: 2376-7308 (Online) Investigation into the Filterability of Raw Sugars from Different Geographical Regions of the World Kamal Suleiman Hassan1, Kanada Toto Korea2, Abubakr Musa1, 3, * 1Sugar Institute, University of Gezira, Wad Madani, Algezira, Sudan 2Alkhaleej Sugar Co., Dubai, UAE 3School of Food and Biological Engineering, Jiangsu University, Zhenjiang, China Email address: [email protected] (A. Musa) *Corresponding author To cite this article: Kamal Suleiman Hassan, Kanada Toto Korea, Abubakr Musa. Investigation into the Filterability of Raw Sugars from Different Geographical Regions of the World. International Journal of Computational and Theoretical Chemistry. Vol. 5, No. 6, 2017, pp. 53-58. doi: 10.11648/j.ijctc.20170506.11 Received: October 19, 2017; Accepted: November 8, 2017; Published: January 2, 2018 Abstract: This study was carried out at Alkhaleej Sugar Refinery in Dubai, United Arab Emirates. The study aimed to find out the correlation between the filterability and slurry resistance value so fraw meltliquor in the carbonation sugar refinery and the raw sugar quality. The investigation utilized 5 raw sugar samples originated from various regions of the world comprising three quality groups namely; low pol sugar (LP) originated from Thailand, very high pol sugar (VHP) originated from Brazil, South-Africa, Sudan, India, and very high pol sugar (VVHP) originated from Brazil. The filterability and the slurry resistance tests were used as the main determining factors for the evaluation. The filterability of refined sugar (consideredas100%) was used as a reference value for comparison.
    [Show full text]
  • Performance Evaluation of Precast Reinforced Concrete After Early-Age Carbonation Curing
    Performance Evaluation of Precast Reinforced Concrete after Early-Age Carbonation Curing Duo Zhang Department of Civil Engineering and Applied Mechanics McGill University, Montreal July 2016 A thesis submitted to McGill University in partial fulfillment of the requirements of the degree of Doctor of Philosophy in Engineering © Duo Zhang, 2016 All Rights Reserved This page is intentionally left blank ABSTRACT Early carbonation curing of precast concrete accelerates early strength and promotes carbon dioxide utilization. Reinforced concrete represents the majority of precast concrete products and thus the application of early-age carbonation technology in reinforced concrete curing is able to enhance the carbon dioxide utilization potential by concrete products for emission reduction and performance improvement. This thesis aims to develop a special carbonation process suitable to high slump precast concrete. The performance of both ordinary Portland cement (OPC) concrete and fly ash-OPC concretes were evaluated. Early carbonation behavior was assessed by carbon uptakes, pH values, compressive strength and process shrinkage. The effect of early carbonation curing on cement reaction, pozzolanic reaction and pore structure was also examined to interpret the mechanisms of durability performance including freeze-thaw resistance, chloride penetration and weathering carbonation. It was found that carbonation curing had reduced both pore volume and pore size. Gel pores became dominant which were responsible for the improved resistance to permeation and freeze-thaw damage. Chemically cement reaction was accelerated in the early age by carbonation curing and concrete pH values could be compensated by subsequent re-hydration. It was concluded that the carbonation curing was suited to the precast reinforced concrete with or without fly ash incorporation in order to gain improved early strength, enhanced durability and permanent carbon dioxide sequestration as an added-value for environmental benefit.
    [Show full text]
  • Synthesis and X-Ray Diffraction Analyses of Calcium Hydroxide Nanoparticles in Aqueous Suspension
    Advances in Materials Physics and Chemistry, 2013, 3, 108-112 http://dx.doi.org/10.4236/ampc.2013.31A013 Published Online April 2013 (http://www.scirp.org/journal/ampc) Synthesis and X-Ray Diffraction Analyses of Calcium Hydroxide Nanoparticles in Aqueous Suspension G. Taglieri1, C. Mondelli2, V. Daniele1, E. Pusceddu3, A. Trapananti4 1University of L’Aquila, Department of Industrial and Information Engineering and Economics, L’Aquila, Italy 2CNR-IOM-OGG Institut Laue Langevin, Grenoble, France 3Institut Laue Langevin, Grenoble, France 4CNR-IOM-OGG, c/o ESRF, Grenoble, France Email: [email protected], [email protected], [email protected], [email protected] Received January 24, 2013; revised March 12, 2013; accepted April 17, 2013 Copyright © 2013 G. Taglieri et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. ABSTRACT Calcium hydroxide nanoparticles in aqueous suspensions (also called nanolime) were successfully employed in Cultural Heritage conservation thanks to the ability of favoring re-adhesion of the pictorial layer on original carbonatic sub- strates or allowing to a better superficial cohesion and protection of treated stones. In this work, we have synthesized nanolime particles in aqueous suspension by two different methods. The produced particles were characterized in the laboratory, in terms of structural and morphological features, by means of X-Ray diffraction powder (XRD) and by transmission electron microscopy (TEM), respectively. Nanoparticles were crystalline, regularly shaped, hexagonally plated and with side dimensions generally ranging from 300 nm to 30 nm or less.
    [Show full text]
  • The Effects of Chemical Purification on the Color of Thin and Thick Juices in Sugar Beet Factories Maryam Arajshirvani1, Mohammad Hojjatoleslami*1
    Nutrition and Food Sciences Research Vol 4, No 2, Apr-Jun 2017, pages:35-41 Original Article The Effects of Chemical Purification on the Color of Thin and Thick Juices in Sugar Beet Factories Maryam Arajshirvani1, Mohammad Hojjatoleslami*1 1- Food Sciences Department, Islamic Azad University, Shahrekord Branch, Iran. Received: October 2016 Accepted: January 2017 A B S T R A C T Background and Objectives: Recognizing the impurities of sugar beet and also comparing different methods of juice purification have shown that the chemical purification based on lime and carbon dioxide is really efficient and economic in the sugar industry. Factories have to control and improve purification stages to achieve clear juice with high chemical purity, low color, minimum hardness, sufficient thermal resistance and with no insoluble solid matters in producing white sugar with high purity and efficiency. The aim of this study was to investigate the effects of alkalinity changes in preliming and liming stages on improving the color of thin and thick juices. Materials and Methods: In the current study, changes in pre-liming alkalinity (0.2, 0.3 and 0.9) and liming alkalinity (1.3, 1.4, 1.5 and 1.6) (mg CaO/ 100 ml juice) during the operation were studied in Sharekrod sugar factory. According to the discharge and retention time of each stage (raw juice, thin juice, and thick juice), the samples were taken and the color changes were studied. Results: The results showed that alkalinity changes of 0.4 in preliming along 1.4 in liming and 0.4 in preliming along 1.3 in liming (mg CaO/ 100 ml juice) caused imbalance of cation/anion, sucrose hydrolysis and invert sugar, and produced undesired color in the thin or thick juice.
    [Show full text]
  • Application of Hydrodynamic Oscillations for Activation of the Hydrated Lime Slurry
    ─── Food Technology ─── Application of hydrodynamic oscillations for activation of the hydrated lime slurry Iryna Dubovkina Institute of Engineering Thermophysics of National Academy of Sciences of Ukraine, Kyiv, Ukraine Abstract Keywords: Introduction. The purpose of this scientific work is to study the impact of the application of hydrodynamic Water oscillations for activation of the hydrated lime slurry in the Hydrated production of sugar from sugar beets. Lime Materials and methods. General scientific methods, Pressure special methods, volume parametric imitation and Oscillation visualization modelling methods, math modelling methods, optical microscopy, and ionometry were used for the researches. Results and discussion. It is established that application Article history: of hydrodynamic oscillations for activation of the hydrated lime slurry in the production of sugar from sugar beets is Received 02.09.2017 very perspective. Received in revised It was established that the value of the linear speeds of a form 13.12.2017 stream should be within 22 m/s for the first rotor and 24 m/s Accepted 29.12.2017 for the second rotor for intensification mass exchange processes between lime and water throughout the activating hydrated lime slurry. Corresponding The research studies demonstrated the increasing of the author: potential of hydrogen of the water prepared for the technology of the activating hydrated lime slurry for the Iryna Dubovkina processes of juice purification within 15%. E-mail: In general case was established that the decreasing of [email protected] reduction-oxidation reaction which obtained throughout processing on an extent 210s, after that there is not large decreasing of the reduction-oxidation reaction.
    [Show full text]
  • Cane Sugar 10 27 2017.Pdf
    Cane Sugar Refining with Ion Exchange Resins Table of Contents Cane Sugar Mills 2 Technical Information 28 Physical Constants of Sucrose 28 Cane Sugar Refining Process 4 Ash vs. Conductivity 30 Raw Sugar Receiving 4 Sucrose Viscosity 30 Affination 4 Melter 4 Regenerant Concentrations 34 Defecation/Clarification 4 Filtration 4 Conversions 35 Decolorization 5 Evaporation 5 Mesh and Slot Sizes 37 Crystallization 5 Amorfo Sugar 6 Resin Technical Data 38 A860S 38 Decolorization 7 A502PS 38 Colorants 8 A420S 38 Color Removal Mechanisms 9 MN102 38 Adsorbents 9 MN150 38 Resin Advantages 11 IP4 38 Service 12 C115EC 38 Direction, Loading, Leakage 13 A500SPlus 38 Odor and Taste 15 A850S 38 Regeneration 16 A440S 38 Sequence, Cleanup Regeneration, 17 PRA420 38 Regeneration Without Brine 18 CT124SH 38 Demineralization 21 ICUMSA Color Testing 39 Liquid Sucrose 21 Liquid Invert 22 Cleaning Organically Fouled Resins 40 Nanofiltration Recovery of Regenerants 23 Tank Capacities 41 Lab Testing Protocol 24 Glossary 42 1 Cane Sugar Refining with Ion Exchange Resins Cane Sugar Refining with Ion Exchange Resins Sucrose is extracted from the sugar cane stalk in a cane sugar Mill, purified and crystallized into a tan colored raw sugar. The sugar we consume must be further refined so as to not impart color, flavor or odor to the foods and beverages it sweetens. In a cane sugar Refinery the raw sugar is remelted and the sucrose is further decolorized with ion exchange resins, carbon or bone char and crystallized into white sugar for industry, consumers and confectioners. Although the ion exchange resins are used in the refinery, it is useful to understand the mill operations also.
    [Show full text]