焙烧过程中阴极类型对阴极热场分布的影响  

Influence of different kinds of cathode carbon blocks on cathode thermal-field distribution in preheating process

作　　者：刘海石[1] 李劼[2] 李翠梅[3] 张钦菘[2] 刘伟[2] 

机构地区：[1]东北大学材料与冶金学院,辽宁沈阳110004 [2]中南大学冶金科学与工程学院,湖南长沙410083 [3]江西科技师范学院通讯与电子学院,江西南昌330013

出　　处：《中南大学学报（自然科学版）》2006年第1期36-40,共5页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(50374081)

摘　　要：以有限元分析软件ANSYS为平台,建立了160 kA铝电解槽焦粒焙烧时的三维1/4整槽模型;对3种典型阴极炭块(半石墨质、半石墨化和石墨化)在给定焙烧条件下的热场分布进行了仿真研究。结果表明:由于这3种炭块的电导率和导热系数依次增大,因此,在相同的焙烧条件下达到焙烧终点(阴极最高温度为1 030℃)时,阴极的温度分布依次变均匀;半石墨化和石墨化阴极与半石墨质阴极相比,其最大温差分别降低了133℃和232℃;阴极表面平均温度分别提高了34℃和57℃;周边糊的平均温度分别提高了77℃和126℃;900℃以上温度所占面积则从52.4%分别提高到63.0%和70.5%;达到相同终点的焙烧时间从96 h分别增加到132 h和205 h。当焦粒层厚度从20 mm增加到30 mm时,石墨化炭块的焙烧时间从205 h缩短到90 h,虽然焙烧效果有所下降,但仍然显著优于其他2种炭块在焦粒层厚度为20 mm时的焙烧效果。A 1/4 full 3D computer model of 160 kA aluminum reduction cell during coke preheating was built by using finite element analysis software ANSYS. The simulation on three typical kinds of cathode carbon blocks （semi-graphitic, semi-graphatizied and graphatizied ） under the same preheating conditions was carried out. The results show that, because the electric and thermal conductivities of the three kinds of blocks increase in order the temperature distribution of the cathode becomes even in order; compared with that of the first kind （the semi-graphitic）, the maximum temperature differences in blocks of the last two （the semi-graphatizied and the graphatizied） are decreased by 133 ℃ and 232 ℃, respectively; the average temperatures on block surface are increased by 34 ℃ and 57 ℃, respectively; the average temperatures in the circumjacent paste are increased by 77 ℃ and 126 ℃; the proportion of block surface with temperature higher than 900℃ increases from 52.4% to 63.0% and 70. 5%, respectively; but the preheating time with the same preheating end-point increases from 96 h to 132 h and 205 h, respectively . When the coke bed thickness increases from 20 h to 30 mm, the preheating time with the kind of the graphatizied is reduced from 205 h to 90 h, and although this measure influences the preheating effect negatively, the preheating effect is still much better than that corresponding to other two kinds of carbon blocks preheated under the condition of 20 mm coke bed.

关 键 词：铝电解槽 焦粒焙烧 ANSYS软件 热场 有限元仿真 

分 类 号：TF821[冶金工程—有色金属冶金] TF806.25