【作者】 付志红；

【导师】 何川； 周家平；

【作者基本信息】 重庆大学 ， 动力工程， 2006， 硕士

【摘要】 LF精炼炉是重庆钢铁公司炼钢厂重要的工艺设备,生产过程中,有大量的烟尘从电极与钢盖的间隙中涌出,给炉前工作环境带来严重的烟尘污染。结合重庆钢铁公司炼钢厂LF精炼炉的现场条件,分析造成该污染的主要因素及影响规律,对LF精炼炉炉前环境的改造具有重要意义。首先结合国内主要钢厂同类炉型的运行情况,对LF炉除尘系统的两种改造方案进行了分析。其一是在电极棒上方增加一个集流顶罩,将在钢盖与电极棒之间外溢的含烟尘气流进行收集,输送到指定的除尘器中进行处理排放。该方案受现场工艺布置的限制,对重庆钢铁公司炼钢厂LF炉不适用;其二是在炉盖抽风道的下部加一个用耐火材料制作的下层小炉盖,将原单层小炉盖改进为双层小炉盖,气流通过下层小炉盖时受阻,流速在两层炉盖间形成的腔室中减小,使烟气更易被引风管所捕集。但在试用过程中多次出现下层炉盖上部积渣,堵塞电极孔,造成电极棒升降困难,生产过程中出现电极相与相之间打弧的的情况,给生产带来安全隐患,该方案也不具备可行性。在立足于对现有设备进行挖潜改造的思想指导下,对除尘系统的风机、输尘管道及除尘器存在的问题进行了分析,发现布袋除尘器的清灰方式不合理,造成阻力过大,送风量达不到设计要求。实施改造后,送风量达到了设计标准,但炉前工作环境的烟尘污染并未能得到有效的解决。通过模拟实验和数值模拟,分析了引风管处断口对炉内压力分布和流量分配造成的影响,发现在现有设备条件下,引风管路与除尘风道的连接处存在的断口是影响重钢LF精炼炉除尘系统效能的重要原因。根据上述工作,提出了采用开合式外罩封闭引风管处断口的改造方案,并给出了数值模拟的改造后可能达到的除尘效果。更多还原

【Abstract】 . The Ladle Furnace is an important device for Chongqing Iron & Steel Corporation. As three leaks between the electrode and the cover of the LF furnace, lots of soot get out from these leaks and it took very much pollution dulling its working. How to deduce the pollution is a very urgent work.At the fist, two ways for deduce the pollution for Ladle Furnace used in some steel corporation analyzed. The one was set a top-cover on the ladle furnace to cover the leaks. But it can’t be used at Chongqing Iron & Steel Corporation because of the height of the building. The other one was add a lower cover to form the double-cover for the ladle furnace. Some investigation showed that as the furnace working, the leaks would be blocked by the steel soot and caused the electrodes jointed.Then the tube and dust catcher be cleaned to test the effect for the pollution. The result showed that if the flows in the tube get the designed velocity, the soot would get out also from leaks between the electrode and the cover of the ladle furnace.Then, we build an experimental equipment of the leaky induced pipe to test the leak’s effect. As a result, we get that as the leak length increasing, the negative pressure of the pipe fits exponential decay and loss of the negative pressure between the two sides of the leak become bigger and the flow quantity of the pipe also fits exponential decay. We used the mathematic model ( k ?εtwo-equation model, non-structural meshing method) to investigate the flow field and track of the soot granule in the ladle furnace and induced pipe. The conclusion was that because of the leakage on the induced pipe, the loss of the negative pressure at the leak was so large, the pressure of the furnace was higher than atmosphere, and the soot granule about 10 percent would get out from the leak between the electrode and the cover. So we declare that the leak between the induced pipe and the ladle furnace cover was the most important reason for the pollution of the ladle furnace. Then we set a way to close the leak for the ladle furnace.更多还原