CONTROLLING AND MONITORING THERMOTE NICAL PARAMETERS OF GLASS MELTING FURNACE

According to the characteristics of the ther-motechnical parameters such as temperature pressure and glass level for glass melting furnace, the design method for monitoring and controlling these parameters is introduced in this paper based on MACROMAX-2 concentrated and dis-tributedcontrol system. The configuration of management information and control loop is described, and research tests were performed to check the functions of system.

TWO-DIMENSIONAL MATHEMATICAL MODEL OF COMBUSTION SPACE IN GLASS MELTING FURNACES

Under some assumptions and dividing the combustion space into several isothermal zones and isothermal surface elements, a two-dimensional mathematical model for combustion space in cross-fired glass melting furnaces was constructed. The finite element method and the Gauss integration were used to calculate direct ex-change areas, and a inverse matrix was used to obtained the total ex-change areas. The temperature distributions were obtained by itera-tions. Some results were presented to show the effects of the fire tem-perature distribution, the convective -heat transfer coefficients and the heat losses through crown surfaces on the temperature distributions.

Innovation of Regenerator Checkerwork for Glass Melting Furnaces

Regenerator checkerwork for glass melting furnaces should have high resistance against thermal stress and chemical attack,high mechanical stability,high efficiency to recover the heat from waste gas and low tendency for clogging.This article reviews the innovation of the regenerator checkerwork from the past decades.The state of the art for optimised material choice and optimised checker shapes will be reported.

Fireclay Refractory Bricks for Glass Melting Furnace

This standard is applicable to fireclay refractory bricks with unit weight ≥ 50 kg for glass melting furnaces.

Sintered AZS Bricks for Glass Melting Furnace

1 Scope This standard specifies the brand, technical requirements, test methods, inspection rules, marking, packing, transportation, storage, and quality certificate of sintered AZS bricks for glass melting furnace. This standard is applicable to sintered AZS bricks for glass melting furnace.

Fused Cast Alumina Refractory Products for Glass Melting Furnace

JC/T 494-92(96) 1 ScopeThis standard specifies the technical requirements, test methods, inspection rules, marking, packing, transportation, and storage of fused cast alumina refractory products for glass melting furnace. This standard is applicable to the fused cast alumina refractory products for glass melting furnace (called products for short).2 Normative ReferencesGB 2997 Test method for apparent porosity, water absorption, bulk density and true porosity of dense shaped refractory productsGB 5072 Test method for cold crushing strength of dense shaped refractory productsGB 5989 Test method for refractoriness under load of dense shaped refractory products (Differential, with rising temperature)GB 7320 Test method for thermal expansion of refractory productsGB 10204 Test method for corrosion resistance of refractories for glass melting furnace to molten glassGB 10325 Stacking, sampling, acceptance, storage and transportation of shaped refractory productsGB 10326 Inspections of dimension, appearance and section of refractory productsGB/T 14351 Chemical analysis method of fused cast alumina refractoriesYB 4015 Sample preparation for testing of refractory products for glass melting furnaceYB 4016 Sampling and inspection of refractory products for glass melting furnaceJC 493 Fused cast zirconia corundum refractory products for glass melting furnace

Silica Refractory Bricks for Glass Melting Furnace

1 Scope This standard specifies the classification, technical requirements, test method, inspection rules, marking, packing, transportation, storage and quality certification of silica refractory bricks for glass melting furRaces.

High Quality Silica Bricks for Glass Melting Furnace

This standard specifies the classification, technical requirements, test method, inspection rules, marking, packing, transportation, storage and quality certification of high quality silica bricks for glass melting furnace.

Low Porosity Fireclay Bricks for Glass Melting Furnace

This standard specifies the classification, technical requirements, test methods, inspection rules, marking, packing, transportation, storage and quality certificate of low porosity fireclay bricks for glass melting furnace.

Investigation of Microstructure and Phase Composition of Chromic Oxide, AZS/Cr and High-alumina Refractories after Exposure of Basalt and Aluminaboronsilicate Glasses Melts

The microstructure and phase composition of high-alumina,chromic oxide,and AZS/Cr refractories containing 30%and 60%(by mass)Cr_(2)O_(3) after exposure to aluminaboronsilicate glasses and basalt melts depending on the type of melts and temperature have been studied.The mechanisms of refractory corrosion by the used melts and the factors contributing to the inhibition of corrosion development have been investigated by the method of petrographic analysis.On the basis of obtained results,the use of high-alumina,chromic oxide,and AZS/Cr refractories in the sections of glass furnace linings,experiencing the intensive impact of aluminaboronsilicate glasses and basalt melts,has been confirmed and scientifically substantiated.

Preparation of B_(2)O_(3)-ZnO-SiO_(2)Glass and Sintering Densification of Copper Terminal Electrode Applied in Multilayer Ceramic Capacitors

B_(2)O_(3)-Zn O-SiO_(2)(BZS)glass containing Cu O with excellent acid resistance,wetting properties,and high-temperature sintering density was prepared by high temperature melting method and then applied in copper terminal electrode for multilayer ceramic capacitors(MLCC)applications.The structure and property characterization of B_(2)O_(3)-Zn O-SiO_(2)glass,including X-ray diffraction,FTIR,scanning electron microscopy,high-temperature microscopy,and differential scanning calorimetry,indicated that the addition of CuO improved the glass’s acid resistance and glass-forming ability.The wettability and acid resistance of this glass were found to be excellent when CuO content was 1.50 wt%.Compared to BZS glass,the CuO-added glass exhibited excellent wettability to copper powder and corrosion resistance to the plating solution.The sintered copper electrode films prepared using the glass with CuO addition had better densification and lower sintering temperature of 750℃.Further analysis of the sintering mechanism reveals that the flowability and wettability of the glass significantly impact the sintering densification of the copper terminal electrodes.

Structure and Coordination Investigation of Iron-ion Tinting Principle in Ferreous Glass

The tinting phenomena of iron oxide contained glasses were studied from aspects of the electronic configuration, the iron ions coordination fields and the ions structure in glass. Several iron ion tinting forms at different redox or COD (chemical oxygen demand) conditions and their influential factors were given necessary explanations. The results reveal that the Fe^(3+)-O-Fe^(2+) structure is the real tinting reason of iron involved glasses, whereas the Si^(4+)-O-Fe^(3+) and Si^(4+)-O-Fe^(2+) formulations modify the glass colours. Under oxidizing melting condition, the amount of 4/6-coordinated Fe^(3+) increases and makes the glass colour yellowish. Conversely, reducing melting condition makes the 6-coordinated Fe^(2+) increased and gives much blue tint to the glass. The conventional tank furnace melting the very strong reducing condition, which is of high COD glass batch, is not suitable. The high ratio of ferrous/ferric in glass can be obtained with a new refining technology which contains no or little amount of refining agent.

Simulation of 3D Heat and Mass Transfer in Glass and Oxide Melts Using the Inductive Skull Melting Technology

The inductive skull melting technology has many advantages for melting of innovative materials in the field of glasses and oxides.It offers high processing temperatures and the compliance of necessary purities at the same time. Applicable materials are in particular optical glasses,which are applied for lenses,fibers or filters,because the skull melting technology allows high process temperatures and high purities of the final product.In the production of glass materials strong requirements have to be fulfilled regarding the optical characteristics,which are mainly defined and influenced by the melting of the raw material and the following refining process.An unsolved problem in the melting process of glasses and oxides using the inductive skull melting technology was in the past the unknown heat and mass transfer in the melt because temperature and melt flow measurements in the melt are practically impossible due to the high temperatures.On the other hand the temperature and velocity distribution in the melt is very important regarding the safety of the melting process,the process control for producing the required properties of the material or the further development of skull melting installations.The paper describes a new numerical model which is able to simulate the instationary 3D melt flow of glasses and oxides.The numerical model takes into account electromagnetic,convection and Marangoni forces.By this a comprehensive view of the hidden processes in the practical experiments could be obtained. By means of the new numerical model different glass and oxide melting processes were simulated and the results were compared with experimental results.The comparisons show first of all a very good agreement between experimental and numerical results at the melt surfaces.Additionally the numerical results allow to look much deeper inside the melt and show interesting new effects of the heat and mass transfer below the melt surface which were unknown before.

Three-dimensional Mathematical Modeling of a Glass Melting System

An integral mathematical model has been developed to simulate the performance of a glass melting system.The heart of the model is a three dimensional flow and heat transfer model capable of calculating the glass flow and temperature distribution in the melt. The glass quality is predicted by using additional sub models for flow tracking, melting kinetics, homogenizing, refining, and refractory corrosion. A sample result is presented to illustrate the analysis of the glass melting process.

Numerical Simulation of Induced Alterations of Flow Patterns Within Glass Melts using External Lorentz Forces

A common way to produce glass is to use melting tanks that work continually with several hundred tons per day.The process of efficiently melting,refining,and homogenizing the glass melt is strongly dependent on the flow patterns within the melting tank.In order to improve the quality of glass products and the efficiency of the melting process,it is necessary to control the flow patterns and to optimize the temperature distribution within the melting tank.Using Lorentz force to create additional flow components based on electric current density distributions and externally generated magnetic fields is an excellent method to obtain targeted and tailored flow influences.In order to evaluate this method,it is necessary to simulate the induced alterations of the melt flow.Such numerical simulations require the coupling of the electromagnetic and flow field calculations including the energy equation because the electrical conductivity of the molten glass is strongly dependent on the temperature.The idea is to include the calculation of the magnetic field completely into FLUENT using the so-called User Defined Scalars(UDS)and User Defined Functions(UDF).

Advances in Investigation of Fe-based Glass-forming Alloy Melts

Continuous precision casting is an important trend in modern industrialization.Clustering effects in glassforming metallic liquids tremendously influence the properties of rapidly quenched ribbons;therefore,much attention has been paid to the study of Fe-based glass-forming melts at high temperatures.Recent investigations of these melts are categorized and reviewed.It is concluded that more efforts are still required to reveal the discipline of amorphization brought about by rapid quenching of Fe-based glass-forming melts.

Electromagnetic Processing of Materials at the Department Inorganic-Nonmetallic Materials

This paper illustrates an overview of current research activities in the working group 'Electromagnetic Processing of Materials' of the department Inorganic-Nonmetallic Materials.These are 'Electromagnetic module to flow impact in special melting plants for the production of High-tech glasses', 'Numerical study of EM controlled flow in crystallizers of inorganic materials', 'Design,test and optimization of sophisticated magnet systems for Lorentz force velocimetry in electrially low conducting fluids', 'Magnetic ion manipulation in glass melts with Kelvin force', 'Electromechanical dry t'me milling of raw materials' and 'Synthesis,characterization and application of Titatium doped hexaferrites'.The primary results are presented here.