【作者】 脱鹏；

【导师】 李贺松；

【作者基本信息】 中南大学 ， 热能工程， 2011， 硕士

【摘要】 随着经济的不断发展,在国民生产生活中铝需求量不断增加,铝工业的规模发展十分迅速。铝电解行业是耗能大户,在世界能源日益紧张的今天,对其进行节能降耗研究是十分必要的。针对国内铝电解槽阳极铁-碳压降过高的现状,本文以ANYSY有限元软件为平台,建立了铝电解槽阳极热场、应力场、电场耦合模型,对铝电解槽阳极铁-碳接触压降进行模拟计算,研究不同磷生铁膨胀性对接触压降的影响、不同质量的阳极炭块与磷生铁膨胀匹配性,并运用所建模型模拟计算了碳碗尺寸、形状的改变对阳极接触电阻的影响。主要成果如下：1)运用ANSYS有限元分析软件建立了含接触电阻的铝电解槽阳极热场、应力场和电场仿真模型,并对其进行了正确性验证。2)讨论了影响接触电阻的各项因素,得出影响铝电解槽阳极铁-碳接触电阻的主要因素为接触压力。针对接触压力为主要影响因素的接触电阻计算公式,通过仿真与现场测试相结合的手段确定铁-碳接触的接触电阻系数Kc,从而实现铝电解槽阳极铁-碳接触电阻的计算。3)运用仿真的手段确定某铝厂最佳磷生铁膨胀系数,仿真结果表明：在确保安全生产的前提下,通过膨胀系数的调整,可以降低阳极接触压降20.4 mV。4)通过不断调整磷生铁膨胀系数,得到不同磷生铁膨胀系数下阳极炭块应力及阳极压降,拟合出膨胀系数与阳极压降的匹配曲线。对各个铝厂不同质量阳极炭块采取不同的磷生铁膨胀系数进行匹配,以期最大限度的减小铁-碳接触电阻。5)针对阳极碳碗尺寸对接触压降的影响进行仿真模拟研究,分别对碳碗直径增大、深度增加进行了热场,应力场和电场研究,并与传统碳碗进行比较,分析总结了不同改造方式对降低阳极接触压降的贡献。6)针对阳极上开槽技术,本文对其进行仿真模拟研究,并与传统阳极进行比较,确定其对接触电阻的影响,并分析了上开槽在实践过程中可能存在的问题。更多还原

【Abstract】 With the development of economy, there is a increasing demand for aluminum production, thus the aluminum industry is developing rapidly. The aluminum industry is a main energy consumer, as the energy crisis, is becoming increasingly serious, it is extremely necessary to conduct research on its energy-saving. To reduce the high contact voltage drop of anode in the aluminum reduction cell, in this paper, the finite element software-ANYSY was used to build thermal, stress, electric field coupled model in aluminum reduction cell anode, and the numerical simulation was conducted for the aluminum anode iron-carbon contact voltage drop. The influences of the expansion of phosphorous pig iron on the contact voltage drop was studied, and the matching attribute of the anode carbon blocks of different qualities and the expansion of phosphorus pig iron were determined. Additionally the model was used to simulate how various the carbon bowl size and shape affect the anode contact resistance. The main results are as follows:1) The finite element software ANSYS was used to build the coupled thermal, stress, electric field model of the aluminum reduction cell anode with contact resistance. Its correctness was verified.2) The various factors which affect the contact resistance were discussed, indicating that the main influence factor of anode iron-carbon contact resistance is the contact pressure. Based on the contact pressure dominated formula of the contact resistance, the coefficient Kc of iron-carbon contact resistance was determined with the combination of simulating and field test. In this way the anode iron-carbon contact resistance could be calculated.(3) The simulation method was used to determine the best expansion coefficient of phosphorus pig iron of a operating smelter, the results show that:on the premise of safety in production, an adjustment of the expansion coefficient of phosphorus pig iron, could decrease the contact voltage drop of the anode to up to 20.4 mV.(4)By adjusting the coefficient of expansion of phosphorus pig iron, the stress of the anode carbon block and the anode voltage drop with different Kc can be obtained, and the curve was fitted between expansion coefficient and the anode voltage drop. Different qualities of anode carbon block in aluminum could be matched with different expansion coefficients of phosphorus pig iron, in order to reduce the iron-carbon contact resistance to the highest extent.(5) The impact of the carbon bowl size on the contact voltage drop was studied numerically, the thermal, stress, electric fields of carbon bowl with increased diameter and depth were compared with the conventional anode, the contribution of the different rehabilitate methods to reduce the anode contact drop were analyzed.(6) The anode upper-surface-slotting technology was numerically studied and compared with the conventional anode. Its’effect on the contact resistance was determined. The possible problems of the technology in practice were analyzed更多还原