气体成分分析判定浮法玻璃气泡来源

气泡是玻璃产品中最主要的缺陷之一,本文主要论述了通过分析玻璃气中的气体成分,判定并帮助解决了一起实际生产中的气泡缺陷.     

耐火材料在玻璃中析出气泡的趋势

众所周知,气泡,即渗入玻璃中的气体,是玻璃主要缺陷之一。渗入大量气泡会破坏玻璃的均一性,减少透光性,降低机械强度和热稳定性。玻璃中气泡的形成与一系列原因有关,其中包括耐火材料与玻璃在接触界面相互作用。相互作用结果产生的气泡,可能出现玻璃内部或玻璃表面处的缺陷。 为了提高玻璃产品质量,需要选择合炭更少的耐火材料,应用在玻璃熔窑的冷却部和成型部,使用时减轻玻璃中形成气泡的程度。 本文所做工作目的,主要是确定测定方法以估价耐火材料在玻璃中析出气泡的趋势,电熔耐火材     

玻璃熔体中气泡行为特征的数学模型

给出了一套描述多组分气泡在玻璃熔体内复杂行为特征的数学模型.该模型可以计算气泡的大小、所在位置、三维速度、运动轨迹、内部气体成份、压力及温度等;根据电视屏玻璃池炉内澄清段的相应工况,模拟了气泡行为;文中给出了气泡在上升过程中半径和气体成分的变化,以初步揭示气泡在玻璃液中的有关行为特征.     

玻璃气泡中α斜方硫成因探讨

利用Ｒａｍａｎ探针和加热方法在普通平板玻璃的气泡壁上发现微米级α斜方硫结石，指出这类气泡的成因与玻璃熔体中单质硫的存在密切相关，并认为单质硫主要来源于原料中的含硫化合物在玻璃熔体中的反应产物。     

平板显示用玻璃基板生产中玻璃液流经铂(合)金通道时气泡产生的原因分析与对策

由于铂及其合金耐高温且化学性质稳定,不与玻璃熔体发生化学反应,因此广泛使用于玻璃基板等精细电子光学玻璃生产中的玻璃液熔化、澄清、调节(降温和均化)、输送和成型过程中。但当铂及其合金与玻璃液接触时,在两者界面会产生大量气泡。本文运用化学热力学和化学平衡理论论述了表面气泡产生的原因和影响因素,得出气泡的产生是由于玻璃液/铂(合)金界面处氧化反应生成的氢气逸出导致富氧层形成造成的,且推导出可用于抑制界面气泡生成的铂(合)金管道(容器)系统周围环境中氢气分压的计算公式,并据此提出了通过控制环境湿度和气氛中氧含量来抑制气泡生成的对策方案。     

对塑料发泡膨胀过程气泡振动的研究

研究了塑料发泡过程的气泡振动行为 ,通过对塑料熔体和气相气体同时进行研究 ,列出了气泡振动的控制方程 ,并进行了离散化处理和数值模拟 ,获得气泡振动的规律 ,讨论了气相气体和塑料熔体的粘弹性对气泡振动的影响 ,为有效控制塑料发泡过程提供理论依据     

对塑料发泡膨胀过程气振动的研究

研究了塑料发泡过程的气泡振动行为,通过对塑料熔体和气相气体同时进行研究,列出了气泡振动的控制方程,并进行了离散化处理和数值模拟,获得气泡振动的规律,讨论了气相气体和塑料熔体的粘弹性对气泡振动的影响,为有效控制塑料发泡过程提供理论依据。     

钨尾矿对钠钙玻璃助熔作用的研究

钨尾矿是钨矿选矿过程中产生的废料,含也SiO_2、Al_2O_3、CaO、K_2O、Na_2O、CaF_2和WO_3.在钠钙玻璃配料中加入钨尾矿后,玻璃熔体中的气泡和砂粒减少,玻璃的粘度和软化点降低.对玻璃性质随钨尾矿用量的变化进行了研究.     

澳洲锂辉石——玻璃行业的新型原材料

正澳洲锂辉石是一种热膨胀系数极低、助熔性极强、品位极高的玻璃原料,素有"工业味精"的美誉。在玻璃配料中添加少量澳洲锂辉石,可降低熔化温度和熔体粘度,拓宽烧成范围,促进澄清均化,减少气泡和杂质;同时,它能降低热膨胀系数,提高产品的抗热震性和耐酸性,减少裂纹,提高玻璃质量和产品理化性能(提高密度、强度、耐内压力和抗冲击性能),以及可改善玻璃表面光洁度和外观质量。澳洲锂辉石是实现玻璃产品上档次,节碱节能,同时是消除部分氟、铅等有害成分,进行科学配方改革的有效途径。     

固态Si颗粒在Na2O-CaO-SiO2多孔微晶玻璃中氧化的均匀性

加入固态Si颗粒为Na2O?CaO?SiO2(NCS)多孔微晶玻璃配合料的气泡成核质点以调控孔结构,研究了固态Si颗粒在NCS配合料形成熔体过程中的氧化行为,用ANSYS模型模拟了NCS多孔微晶玻璃配合料的热场分布. 结果表明,固态Si颗粒在NCS熔体形成过程中的氧化始于650℃,固态Si颗粒具有促进NCS配合料热场均匀分布的作用,且在NCS熔体形成过程中氧化程度相同,氧化过程不会影响NCS多孔微晶玻璃孔径分布的均匀性.     

通过气泡成分分析解决超白浮法玻璃生产中的气泡缺陷

气泡是玻璃生产中最常见的玻璃缺陷之一,由于它的大小、密度、位置的不确定性,增加了对气泡缺陷来源诊断的难度。超白浮法玻璃生产中气泡更是影响玻璃质量的主要缺陷,通过测定气泡中气体的组成含量,可以较准确、快速地判断该缺陷产生的根源,从而采取有效措施消除缺陷。     

Equilibrium and Transport Properties of Gases in E-Glass Melts

The solubility and diffusion coefficients of oxygen, sulfur dioxide, and water were determined (and those for nitrogen, carbon dioxide, and argon were estimated) in commercial E-glass melts as a function of melt temperature and atmosphere. Knowledge of these fundamental constants of gases in glass melts is required for the development of models for bubble growth and elimination within the melt. The effectiveness of fining agents can be traced to the production of those gases in the melt which possess the greatest variation in solubility and diffusion as a function of the temperature and atmosphere. Accordingly, oxygen through multivalent elements and sulfur are the best fining agents for glass production.     

Simultaneous absorption and reaction of two gases: absorption of CO2 and NH3 in water and aqueous solutions of alkanolamines

Some aspects of simultaneous absorption and reaction of two gases in an inert medium, and a medium containing species which react with one of the dissolved gases have been considered. Experiments were made on simultaneous absorption of carbon dioxide and ammonia in water and aqueous solutions of mono- and di-ethanolamine in a 5 cm i.d. continuous glass bubble column. A good agreement between the experimental and predicted values was observed.     

Behavior of Bubbles of Oxygen and Sulfur Dioxide in Soda-Lime Glass

Bubbles of sulfur dioxide are dissolved by soda-lime glass containing arsenic or ferric oxide at a rate which follows a square-root-of-time law, indicating a diffusion process. Mixtures of sulfur dioxide and oxygen are dissolved very rapidly as long as both gases are present, whereas an excess of either gas remaining in the bubbles is adsorbed at the normal rate, which depends on the composition of the glass. Apparently sulfur dioxide is dissolved by oxidation either by oxygen in the bubble or by oxygen diffusing from oxidizing constituents in the glass, whereas oxygen is dissolved by diffusing into the glass to react with reducing constituents.     

化学法在空心玻璃微珠制备中的应用

对当前化学法在制备空心玻璃微珠的应用进行了综述,分析了国内外空心玻璃微珠的生产现状以及我国当前空心玻璃微珠的研制技术水平;介绍了空心玻璃微珠的特性,并介绍了空心玻璃微珠的一些实际应用,并对空心玻璃微珠制备方法的发展作了预测:干凝胶法是今后的主流方法之一。     

Dissolution of Multicomponent Bubbles

The behavior of an isolated, stationary, multicomponent gas bubble in a glassmelt containing several dissolved gases is considered. The relevant mass-transport equations are formulated and calculations are performed for the case of two diffusing gases using a quasi-stationary model and a numerical solution of the exact mass-transfer equations. The results obtained from these two approaches are compared. The factors which govern the dissolution or growth of a bubble are thermodynamic and kinetic in origin. The tendency of a bubble to grow or shrink at long times is controlled by departure from overall equilibrium, whereas the short-time bubble dynamics may be dominated by kinetic effects. As a result of the existence of these dual influences, maxima and/or minima occur in the functional dependence of the bubble radius on time.     

Experimental study of bubble formation in a glass-forming liquid doped with cerium oxide

This work aims to study the mechanisms of oxygen bubble formation coming from redox reaction of a polyvalent element incorporated in a glass melt. Borosilicate glass composition is selected for its use as a glass matrix for nuclear waste conditioning. Cerium is selected as a polyvalent element as it may be found in nuclear waste. The chosen material is characterized in terms of physical properties which influence bubble formation and growth. A postmortem optical microscope approach is used to observe bubbles in the investigated material after thermal treatment for varying temperatures (900°C-1100°C) and durations. To support the understanding of oxygen bubble formation, cerium speciation by X-ray absorption near-edge structure (XANES) and bubble gas composition are experimentally evaluated. In this article, we indicate how bubbles are formed in the investigated glass melt system. It is also demonstrated that the mechanisms that govern bubble evolution are fundamentally the same and that the plot's optimum points are strongly influenced by the temperature. These last statements are confirmed by considering some bubble features, such as bubble mean density and bubble mean diameter evolutions, and normalizing the experimental time using a characteristic residence time (t_η) obtaining thereafter a dimensionless time, which is a function of the glass melt properties obtained by the physical characterizations. The impact of temperature and time on bubble formation is described.     

浮法玻璃固定气泡的研究与治理

简述了浮法玻璃中气泡形成的机理和类型,着重对某公司固定气泡形成的位置和原因进行了分析,通过增设池底风机、调整池底风量、更换新矿点、改善对辊破碎方式等措施,可有效解决固定气泡的问题,效果显著。     

The Effect of Basicity on Clarification of Lead Silicate Glasses

The effect of the basicity of glass on its bubble content is studied taking silicate optical flints as example. It is found that the increase in bubble content is symbate with the growth in the content of bivalent iron and glass basicity. It is demonstrated that an increase in the concentration of clarifiers does not decrease the bubble content.