Chemical Reactions in a Soda-Lime Silicate Batch

2008 ◽  
Vol 39-40 ◽  
pp. 459-464
Author(s):  
František Novotný ◽  
Rostislav Lošot
Keyword(s):  
Chemical Reactions ◽  
Raw Materials ◽  
Glass Melting ◽  
Reaction Pathway ◽  
Melting Process ◽  
Soda Lime ◽  
Reaction Pathways ◽  
Technological Properties ◽  
Present Contribution ◽  
Principal Reaction

Primary chemical reactions among the raw materials composing the batch give rise to various transitory intermediate products. Their physical properties influence the character of the glass melting process. The reaction pathway can be controlled by selecting the conditions, e.g. the grainsize composition of raw materials or the heating rate, which will influence the efficacy of the subsequent fining process. The present contribution describes practical technological properties of a couple of principal reaction pathways. A relationship between the practical monitoring of the actual glass melting process and the occurrence of peculiar chemical specimens is also mentioned.

Study of Melting Ability of Granulated Glass Batch

2016 ◽  
Vol 690 ◽  
pp. 272-275
Author(s):  
Kanit Tapasa ◽  
Ekarat Meechoowas ◽  
Suwannee Thepbutdee ◽  
Amorntep Montreeuppathumb
Keyword(s):  
Glass Furnace ◽  
Waste Heat ◽  
Raw Materials ◽  
Glass Batch ◽  
Glass Melting ◽  
Glass Production ◽  
Melting Process ◽  
Soda Lime ◽  
Soda Lime Glass ◽  
Preheating Temperature

In the conventional soda-lime glass production, loose raw materials are normally mixed into a glass batch for melting. Dusting and segregation of the loose glass batch are always occurred during the melting process inside the glass furnace. Also, the loose glass batch has low thermal conductivity which limits the glass melting ability and pulling rate of the glass furnace. Granulation and preheating of glass raw materials have been proposed to solve the problems. In this study, the granulated soda-lime glass batch (SiO2 50% Na2CO3 22.5% CaCO3 12% NaAlSi3O8 9.5% BaCO3 2.5% ZnO 1.75% Sb2O3 1% and K2CO3 0.75% by weight) was prepared to study the melting ability in an electric furnace. The granulated batch was also preheated at 500-600°C before melting. The preheating temperature was matched to the temperature of flue gas at the bottom of the stack in the glass furnace. The purpose behind this was aiming to recover the waste heat from the furnace. The experiment exhibited the increased melting ability for the granulated-preheated glass batch

Investigation of Melting Behavior of Low-Enthalpy Glass Batches

2014 ◽  
Vol 608 ◽  
pp. 311-315 ◽  
Author(s):  
Kanit Tapasa ◽  
Ekarat Meechoowas ◽  
Usuma Naknikham ◽  
Tepiwan Jitwatcharakomol
Keyword(s):  
Raw Materials ◽  
Glass Batch ◽  
Glass Melting ◽  
Kinetic Property ◽  
Melting Process ◽  
Soda Lime ◽  
Melting Behavior ◽  
Soda Lime Glass ◽  
Chemical Heat ◽  
Heat Demand

Batch modification with low-enthalpy raw materials is the effective approach for reducing the glass melting energy. In the previous study, it was found that introducing wollastonite (CaSiO3) as a source of CaO instead of calcium carbonate (CaCO3) in the soda-lime glass batch can fasten the melting process. It is because the modified batch with CaSiO3 has lower chemical heat demand, ΔHochem, which is equivalent to the standard heat of batch-to-melt conversion. In order to investigate the kinetic property of the modified batch, the melting behaviour of 2 kg modified batch was studied. The results showed that the temperature of the modified batch increased at a faster rate than the original batch. The properties of the glass from the modified are also similar to the original batch.

scholarly journals Melting Process and Viscosity of Bohemian Historical Glasses Studied on Model Glasses

Minerals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 829
Author(s):  
Karolína Pánová ◽  
Kristýna Jílková ◽  
Dana Rohanová ◽  
František Lahodný ◽  
Dagmar Galusková ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Production Process ◽  
Technological Progress ◽  
Raw Materials ◽  
Glass Melting ◽  
Melting Process ◽  
Melting Characteristics ◽  
Thermal Dilatation ◽  
Materials Used ◽  
Insight Into

Analyzing the chemical composition of archaeological glasses can provide an insight into their provenance and raw materials used in their making. However, to the authors’ knowledge, the historical production process itself and melting characteristics of the glasses have not yet been extensively investigated. The main focus of this paper is to describe the melting process of three main types of Bohemian historical glasses: Gothic (14th–1st half of 16th c.); Renaissance (16th–17th c.); and Baroque (end of 17th–18th c.). The model glasses were prepared from natural raw materials and processes that take place during melting were investigated using optical microscopy, SEM-EDS, XRD, and DTA-TG methods. Furthermore, the viscosity of model glasses and thermal dilatation was measured and used to calculate the reference viscosity points. The results illustrate the complexity of historical glass melting, as well as the technological progress between different periods.

Alternative Soda-Lime Glass Batch to Reduce Energy Consumption

2013 ◽  
Vol 545 ◽  
pp. 24-30 ◽  
Author(s):  
Ekarat Meechoowas ◽  
Kanit Tapasa ◽  
Tepiwan Jitwatcharakomol
Keyword(s):  
Melting Temperature ◽  
Raw Materials ◽  
Glass Batch ◽  
Heat Content ◽  
Melting Process ◽  
Soda Lime ◽  
Raw Material ◽  
Soda Lime Glass ◽  
Kinetic Properties ◽  
Atmosphere Temperature

Soda-lime glass is produced by melting sand (SiO2), soda ash (Na2CO3), lime stone (CaCO3) together with effective additives such as dolomite (CaMg(CO3)2) and an important structural modification, alumina (Al2O3) in which the melting temperature is very high around 1500°C. With this reason, to dissolve alumina, high amount of energy is needed. Consequently, one of possibilities to reduce the melting energy is replacing alumina by the raw material with a lower enthalpy of melting. The heat required for melting the batch of raw materials from atmosphere temperature to melting temperature is called exploited heat (Hex), which can be calculated from chemical enthalpy (H°chem) and heat content (Hmelt) at reference temperature (Tex). From thermodynamic approach, chemical enthalpy of alumina is higher than feldspar (KAlSiO3) or pyrophyllite (Al2Si4O10(OH)2). For the glass batch with alumina, the calculated exploited heat is 540 kWh/ton while the batch with feldspar or pyrophyllite is lower, namely 534 and 484 kWh/ton, respectively. This means that the melting process can be emerged easier than the batch with alumina because the melting point of feldspar is around 1200°C and pyrophyllite dehydroxylates around 900°C. The kinetic properties of batch melting were investigated by Batch-Free Time method, which defines the melting ability of the modified batch. According to thermodynamic calculation, it was found that both alternative batches were melted easier. The study showed that feldspar or pyrophyllite could be used instead of alumina without significant changes in glass chemical composition and physical properties. The concern of using feldspar or pyrophyllite is the quantity of minor impurities which affect to the color appearance especially in clear glass products.

Effect of Mechanical Activation on the Heat of Fusion of a Conventional Batch Used for the Manufacture of Float Glass

MRS Advances ◽  
2019 ◽  
Vol 4 (57-58) ◽  
pp. 3171-3180
Author(s):  
J. López-Cuevas ◽  
G. Vargas-Gutiérrez ◽  
P.P. Rodríguez-Salazar ◽  
S.R. Ruiz-Ontiveros
Keyword(s):  
Mechanical Activation ◽  
Raw Materials ◽  
Chemical Reactivity ◽  
Melting Process ◽  
Soda Lime ◽  
Initial Mixture ◽  
Float Glass ◽  
Heat Of Fusion ◽  
Activation Process ◽  
Batch Melting

ABSTRACTAn initial mixture of raw materials (batch) typically used for the manufacture of conventional soda-lime float glass was subjected to a mechanical activation process for 30 or 60 minutes in a planetary ball mill. An intensification of the chemical reactivity of the batch, which was directly related with the increase in the milling time, was observed. This accelerated the chemical reactions that took place during the batch melting process between sodium, calcium and magnesium carbonates and other components of the mixture, which happened at significantly lower temperatures with respect to the batch without mechanical activation. The heat of fusion of the batch, estimated using a methodology previously reported in the literature, indicated that the mechanical activation given to the initial mixture of raw materials decreased the energy consumed during the batch melting. This was also evidenced by a decrease in the temperature at which the release of CO2 ended, which was considerably larger than that previously reported in the literature based solely on the decrease in the particle size of a batch of similar composition achieved by dry sieving.

Fabrication of Glass Furnace for Research Scale: Case Study for Soda Lime Silicate Melting Process

2014 ◽  
Vol 979 ◽  
pp. 409-412
Author(s):  
K. Boonin ◽  
S. Tuscharoen ◽  
J. Kaewkhao ◽  
N. Sangwaranatee
Keyword(s):  
Optical Properties ◽  
Physical Properties ◽  
Heat Loss ◽  
Glass Furnace ◽  
Energy Cost ◽  
Raw Materials ◽  
Melting Process ◽  
Soda Lime ◽  
Made In

In this work, glass furnace for research scale has been fabricated using domestic raw materials. Furnace was designed and assembled in laboratory for reduce the heat loss due to openings when load out crucible from furnace, reduce energy cost and increase the number of glass samples that can be made in one working time. Glasses based soda lime silicate formulas have been prepared using the normal melt-quench technique for furnace testing. The result found that good optical properties and physical properties of glasses were obtained.

Some Opportunities to Improve Glass Melting

2008 ◽  
Vol 39-40 ◽  
pp. 453-458
Author(s):  
Lubomír Nĕmec ◽  
Marcela Jebavá
Keyword(s):  
Glass Melting ◽  
Specific Energy Consumption ◽  
Melting Process ◽  
Soda Lime ◽  
Bubble Nucleation ◽  
Sulfur Compounds ◽  
Point Of View ◽  
Bubble Behavior ◽  
The Impact ◽  
Bubble Removal

The values of the specific energy consumption and the melting performance calculated from laboratory measurements of soda-lime-silica glass predict efficient sand dissolution and bubble removal under conditions of rapid melting kinetics and high utilization of the melting space. The impact of glass flow character on bubble removal was investigated in the continuous horizontal or vertical melting channel. The results gave a chance to control the fining performance of the channel by proper temperature boundary conditions. The model of the bubble behavior under effect of both gravitational and centrifugal force has been established in the rotating discontinuous cylinder. The separation of bubbles by centrifuging was influenced by bubble contraction and by partial or complete dissolution in the melt; optimum conditions of the process, applicable in practice, lie in the region of relatively low rotation velocities. Sulfur compounds as chemical accelerator of glass melting were investigated from the point of view of several processes: sand dissolution, fining, bubble nucleation and melt foaming. The experimental work attempts to present the picture of glass melting with sulfur compounds in its complexity. The presented subjects are intended to contribute to advanced glass melting process.

Catalytic Resonance Theory: Parallel Reaction Pathway Control

2019 ◽  
Author(s):  
M. Alexander Ardagh ◽  
Manish Shetty ◽  
Anatoliy Kuznetsov ◽  
Qi Zhang ◽  
Phillip Christopher ◽  
...  
Keyword(s):  
Chemical Reactions ◽  
Active Site ◽  
Active Sites ◽  
Reaction Pathway ◽  
Control Strategies ◽  
Oscillation Amplitude ◽  
Catalytic Performance ◽  
Parallel Reaction ◽  
Resonance Theory ◽  
Static Conditions

Catalytic enhancement of chemical reactions via heterogeneous materials occurs through stabilization of transition states at designed active sites, but dramatically greater rate acceleration on that same active site is achieved when the surface intermediates oscillate in binding energy. The applied oscillation amplitude and frequency can accelerate reactions orders of magnitude above the catalytic rates of static systems, provided the active site dynamics are tuned to the natural frequencies of the surface chemistry. In this work, differences in the characteristics of parallel reactions are exploited via selective application of active site dynamics (0 < ΔU < 1.0 eV amplitude, 10<sup>-6</sup> < f < 10<sup>4</sup> Hz frequency) to control the extent of competing reactions occurring on the shared catalytic surface. Simulation of multiple parallel reaction systems with broad range of variation in chemical parameters revealed that parallel chemistries are highly tunable in selectivity between either pure product, even when specific products are not selectively produced under static conditions. Two mechanisms leading to dynamic selectivity control were identified: (i) surface thermodynamic control of one product species under strong binding conditions, or (ii) catalytic resonance of the kinetics of one reaction over the other. These dynamic parallel pathway control strategies applied to a host of chemical conditions indicate significant potential for improving the catalytic performance of many important industrial chemical reactions beyond their existing static performance.

scholarly journals Waste and Solar Energy: An Eco-Friendly Way for Glass Melting

2021 ◽  
Vol 5 (2) ◽  
pp. 16
Author(s):  
Isabel Padilla ◽  
Maximina Romero ◽  
José I. Robla ◽  
Aurora López-Delgado
Keyword(s):  
Solar Energy ◽  
Environmental Sustainability ◽  
Raw Materials ◽  
Glass Melting ◽  
Glass Network ◽  
X Ray Diffraction ◽  
X Ray ◽  
Concentrated Solar Energy ◽  
Calcium Source ◽  
The Aluminum Industry

In this work, concentrated solar energy (CSE) was applied to an energy-intensive process such as the vitrification of waste with the aim of manufacturing glasses. Different types of waste were used as raw materials: a hazardous waste from the aluminum industry as aluminum source; two residues from the food industry (eggshell and mussel shell) and dolomite ore as calcium source; quartz sand was also employed as glass network former. The use of CSE allowed obtaining glasses in the SiO2-Al2O3-CaO system at exposure time as short as 15 min. The raw materials, their mixtures, and the resulting glasses were characterized by means of X-ray fluorescence, X-ray diffraction, and differential thermal analysis. The feasibility of combining a renewable energy, as solar energy and different waste for the manufacture of glasses, would highly contribute to circular economy and environmental sustainability.

scholarly journals First insights into the archaeometric analysis of the Los Amores Mosaic in Cástulo (Linares, Spain): the Judgement of Paris

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Alberto Sánchez ◽  
José Tuñón ◽  
Manuel Montejo ◽  
Pilar Amate ◽  
Bautista Ceprián ◽  
...  
Keyword(s):  
Raw Materials ◽  
Principal Component ◽  
Soda Lime ◽  
Degradation Process ◽  
Lead Glass ◽  
Non Invasive ◽  
Stone Materials ◽  
Data Assessment ◽  
Siliciclastic Rocks ◽  
Judgment Of Paris

AbstractThis paper discusses results obtained from in situ analysis of the tesserae of the Roman mosaic of Los Amores (Cástulo site, Linares, Spain) dating back to the turn of the 1st to the 2nd century AD. Specifically, it focuses on the scene The Judgment of Paris. In view of the exceptional state of preservation of the mosaic, from which very few tesserae had fallen off, non-invasive methods with portable Micro Raman Spectroscopy (MRS) and hand-held X-ray fluorescence (hXRF) and data assessment by use of principal component analysis and binary representations were selected. The results obtained allow to evaluate both the analytical method and the portable equipment used, as well as to classify the raw materials, the colouring agents and the opacifiers used. MRS analysis proved crucial for the identification of stone tesserae (ironstones, carbonate and siliciclastic rocks) and for the identification of the type of glasses used (soda-lime-silicate and lead type glasses) based on the analysis of two detached tesserae. hXRF analysis of the glass tesserae identified both colouring agents (Co, Cu, Pb, Zn) and opacifiers (calcium antimonate). The data obtained lend themselves to an assessment of the degradation process that threaten the integrity of the mosaic. The identification of tessera made of specific stone materials (especially ironstone) and of lead glass tesserae suggest the existence of a mosaic workshop in the Upper Guadalquivir (Eastern Andalusia, Spain).

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