全氧燃烧条件下水蒸气与玻璃熔体的反应及对玻璃结构和性能影响的研究

发布时间：2018-03-04 01:05

  本文选题：全氧燃烧　切入点：熔制气氛　出处：《海南大学》2015年硕士论文　论文类型：学位论文

【摘要】：近几年,节能减排、提高玻璃成品率,已成为玻璃行业所关注的课题。以此为背景的全氧燃烧浮法熔窑技术在世界范围内获得了非常广泛的研究与应用。Oxy-Fuel(全氧燃烧)是用02替代空气成为助燃气体与燃料混合燃烧的技术。与传统空气助燃技术相比,全氧燃烧工艺在节能减排的同时还能提升玻璃质量,是浮法玻璃窑炉未来发展的新方向。 玻璃是由多相多组分晶态矿物原料经过高温且复杂的物化反应最终形成均匀非晶态物质的一个过程。因此,玻璃的制备是一种典型的物质反应过程。全氧燃烧玻璃熔窑技术的最大特点是窑炉气氛的改变,玻璃熔窑中水蒸汽含量达到50%以上。玻璃熔体吸收水汽的能力特别强,熔体与水蒸气大面积接触,致使水分进入玻璃体后发生反应并对玻璃的结构网络产生影响,导致玻璃的质量和性能发生改变。水进入玻璃体后与玻璃熔体发生理化反应会对玻璃的结构网络、质量、性能产生何等的影响具有十分重要的研究价值。文本通过实验室高温气氛炉模拟全氧燃烧熔窑气氛(H2O:CO2=1:1)和过量水蒸气气氛,探索全氧燃烧熔制环境下玻璃配合料的最佳方案。同时,对全氧燃烧玻璃试样的结构网络、羟基含量、热膨胀系数、气泡、耐水性及显微硬度等性能进行测试,对影响全氧燃烧玻璃质量及性能的各重点因素进行了分析讨论。得出如下 结论： 1.全氧燃烧条件下芒硝含率1.5～2.0%、碳粉含率3.0%时玻璃的澄清质量最好。 2.与空气助燃相比,全氧燃烧过量水蒸气气氛燃烧环境下随着玻璃熔体中羟基(-OH)含量的增多,玻璃的维氏显微硬度平均下降了约5.6%。玻璃的热膨胀系数升高,玻璃的耐水性、软化点温度以及玻璃中气泡数目都逐渐降低。 3.全氧燃烧环境下,通过实验发现全氧燃烧配合料中最好使用低含水量碎玻璃,避免使用高含水碎玻璃所造成玻璃中含水量过高而导致性能大幅度减弱的问题。同时使用低含水碎玻璃的用量在35%左右为宜。 4.29Si MAS-NMR结果显示高含水玻璃结构网络中Q(4)比例减少,Q(3)和Q(2)比例升高。水蒸汽对玻璃熔体内部网络结构产生了影响,玻璃体结构网络的变化对玻璃性能有显著的影响。 5.通过计算发现在全氧燃烧条件下(H2O:CO2=1:1)玻璃熔体中碱含量损失比空气助燃多0.0925mass%。因此全氧燃烧玻璃配合料要比空气助燃配合料中纯碱的挥发率基值高出0.352%左右才能确保全氧燃烧玻璃成品中碱含量的稳定。 6.实验室模拟全氧燃烧工艺条件下采用高温熔化(1580℃、0.5h)和低温澄清(1450℃、3h)能有效减少玻璃熔体中气泡数量,提高玻璃质量。
[Abstract]:In recent years, energy saving and emission reduction, improving glass yield, In this background, full oxygen combustion float furnace technology has been widely studied and applied all over the world. Oxy-Fuel.Oxy-Fuel is to replace air to become combustion gas and combustion. Combustible combustion technology. Compared with conventional air combustion technology, Total oxygen combustion process can improve the quality of glass while saving energy and reducing emissions, which is a new direction for the development of float glass kiln in the future. Glass is a process in which heterogeneous multicomponent crystalline mineral materials undergo high temperature and complex physicochemical reactions to form homogeneous amorphous substances. The preparation of glass is a typical material reaction process. The most characteristic of the glass furnace technology is the change of atmosphere in the furnace. The water vapor content in the glass furnace reaches more than 50%. The glass melt has a particularly strong ability to absorb water vapor. When the melt is in contact with the water vapor in a large area, the moisture will react when it enters the vitreous body and affect the structure network of the glass. It changes the quality and properties of the glass. When water enters the glass body, it reacts with the glass melt in physical and chemical way, which will affect the structure and quality of the glass. It is of great value to study the effect of performance. The paper simulates the atmosphere of total oxygen combustion furnace H _ 2O _ 2 CO _ 2 / 1: 1) and excess steam atmosphere through a laboratory high temperature atmosphere furnace. The optimum scheme of glass mixture in the environment of total oxygen combustion and melting was explored. The properties of structure network, hydroxyl content, thermal expansion coefficient, bubble, water resistance and microhardness of the glass sample were tested. The key factors affecting the quality and properties of the total oxygen combustion glass are analyzed and discussed. The following results are obtained. Conclusion:. 1. Under the condition of total oxygen combustion, the quality of clear glass is the best when the content of glauber is 1.5 ~ 2.0 and the content of carbon powder is 3.0. 2.Compared with air combustion, the Vickers microhardness of the glass decreased by about 5.6 with the increase of the content of hydroxyl group in the glass melt, and the thermal expansion coefficient of the glass increased, and the water resistance of the glass increased, and the water resistance of the glass increased with the increase of the content of hydroxyl group in the glass melt. The softening point temperature and the number of bubbles in the glass gradually decreased. 3. In the environment of total oxygen combustion, it is found that it is best to use broken glass with low water content in the mixture of total oxygen combustion. To avoid the problem of excessive water content in glass caused by the use of high water content broken glass, which leads to the greatly weakening of properties. At the same time, it is appropriate to use low water content broken glass at about 35%. 4.29Si MAS-NMR results show that the ratio of Q _ (4) and Q _ (2) increases in the glass network with high water content. Water vapor has an effect on the internal network structure of glass melt, and the change of glass structure network has a significant effect on the glass properties. 5. It is found by calculation that the loss of alkali content in glass melts is 0.0925% more than that in air-assisted combustion under the condition of total oxygen combustion. Therefore, the volatilization base value of soda in total oxygen combustion glass mixture is about 0.352% higher than that in air combustion-supporting mixture. To preserve the stability of alkali content in the finished product of oxygen combustion glass. 6. Under the conditions of simulated total oxygen combustion in laboratory, high temperature melting (1580 鈩，

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