更新时间:02-23 上传会员:刘教授
分类:工业大学 论文字数:15484 需要金币:1000个
摘要:低分子比电解质具有熔点较低,蒸汽压低,电解质流动性好,密度较小等优点,是铝电解生产实现高效率低消耗的重要途径。初晶温度是铝电解质的一个重要性质,它影响电解质的挥发性、流动性、金属与电解质的分离和金属的溶解损失,并且直接决定电解温度。铝电解生产实现节能减耗的重要途径是控制好过热度,控制过热度的关键在于准确地获取初晶温度,由此可见,稳定可靠地测定低分子比铝电解质初晶温度的方法就显得尤为重要。步冷曲线法直接测定初晶温度时间短, 测温结果可靠, 所用的保护套管延长了测温传感器的使用寿命。本文讨论初晶温度的一些测定方法,并探索将步冷曲线法和变化率计算法结合起来测定低分子比电解质的初晶温度,研究影响实验结果准确性的因素。影响实验结果准确度的因素有:热电偶头部深入熔融电解质的深度、位置,电阻炉的密封性,电解质的冷却速度,样品测定的重复性。实验证明该方法可行、可靠,与其他方法相比较准确性和稳定性良好。
关键词: 初晶温度 步冷曲线法 热力学计算 测定方法
ABSTRACT:Low molecular ratio of electrolyte has a low melting point, vapor pressure, electrolytes, good fluidity, low density, etc., is an important way for the aluminum production to achieve high efficiency low consumption. Aluminum liquidus temperature is an important property of the electrolyte, it affects the volatility of the electrolyte, mobility, metals and electrolyte loss of separation and dissolution of the metal, and directly determines the electrolysis temperature. Controlling degree of superheat well is an important way for aluminum production to save energy, obtain liquidus temperature accurately is the key to superheat control, shows that a stable and reliable method to determinate the liquidus temperature of low molecular ratio of electrolyte is particularly important. Determining liquidus temperature with cooling curve method directly need short time, temperature measurement results are reliable, using protective casing extended temperature sensor life. This article discussed some of liquidus temperature measuring methods, explored determining the liquidus temperature of low molecular ratio of electrolyte with the way to combine the method of rate of change calculations and cooling curve method, the accuracy of the factors that affect the results. Affect the results accuracy factors: thermocouple head depth of the molten electrolyte depth, position, sealing resistance furnace, the cooling rate of the electrolyte, sample measurement repeatability. Experiments show that the method is feasible and reliable compared with other methods, accuracy and stability.
Key word:Liquidus temperature; cooling curve method;Thermodynamic calculations; Determination method