铝电解槽侧壁换热系统的仿真与应用  

Simulation and Application of Heat Exchanger System on the Sidewalls of an Aluminum Reduction Cell

作　　者：明勇 周乃君[1] MING Yong;ZHOU Nai-Jun(School of Energy Science and Engineering,Central South University,Changsha 410083,China)

机构地区：[1]中南大学能源科学与工程学院

出　　处：《工程热物理学报》2019年第9期2115-2125,共11页Journal of Engineering Thermophysics

基　　金：湖南省科技计划重点项目(No.2009GK2009)

摘　　要：本文提出了利用有机朗肯循环对铝电解槽侧壁的余热进行回收利用,考虑到电解槽侧壁的实际情况设计了一种新型的换热器。为了了解在侧壁余热利用过程中是否会对电解槽的正常运行产生影响,运用ANSYS软件建立了200 kA铝电解槽的三维有限元模型,并对其有无换热器的情况分别进行了热-电耦合模拟。模拟结果显示:在加载换热器后,电解槽侧壁温度明显降低,槽帮厚度适当增加,槽电压略有降低。在此基础上设计了一套侧壁余热发电系统,为了掌握整个系统的有效能流向,对系统进行了[火用]分析。分析结果:系统的[火用]损主要集中在节流过程和冷凝过程,为提高系统效率提供了方向。对系统参数进行了优化,优化结果表明:在换热器出口参数一定的情况下,随着汽轮机进气压力升高,系统循环效率逐渐升高而发电量会出现一个峰值。本文为电解槽余热利用提供了新的途径。An idea that using the waste heat on the sidewalls of an aluminum reduction cell by the method of Organic Rankine Cycle was proposed;taking into account the actual situation of an aluminum reduction cell’s sidewalls a new-type heat exchanger was designed.In order to know whether the side wall’s waste heat utilization will affect the normal operation of the aluminum reduction cell;a three-dimension finite element model of 200 kA aluminum reduction cell is established based on ANSYS software,and the coupled thermo-electric simulation for a 200 kA cell was analyzed under installing the exchanger or not.The simulation results show sidewall temperature decreased obviously,freeze thickness increased appropriately,cell voltage decreases slightly after installed exchanger.Based on the above,a sidewall waste heat power generation system was designed;In order to grasp the flow of effective energy of the system has carried on the exergy analysis.The analysis results show exergy loss of the system mainly concentrated in the throttling process and the condensation process,providing the direction for improving the system efficiency.The system parameters were optimized;The optimization results show in the case of outlet parameters of the heat exchanger were fixed,with the inlet pressure increases,the system efficiency increased gradually while the amount of power generation would be a peak.In this paper,for the aluminum cell provides a new way of utilizing waste heat.

关 键 词：铝电解槽 换热器 余热发电 热场 数值模拟 [火用]分析 

分 类 号：TK124[动力工程及工程热物理—工程热物理]