【作者】 李建伟；

【导师】 邹宗树；

【作者基本信息】 东北大学 ， 钢铁冶金， 2013， 硕士

【摘要】 在传统的焦化、烧结和球团工序中,回收炉料的中低温显热不彻底,能量利用率低,造成大量的热量浪费,因此本文提出基于炉料连续热装的氧气高炉炼铁工艺,并建立与之匹配的铁前系统工艺模型,试图寻求最优的工艺参数。本文以物料平衡和能量平衡为基础,建立了铁前系统模型,包括热装氧气高炉工艺模型、焦化工艺模型、烧结工艺模型和球团工艺模型。通过模型计算,研究了富氧率、鼓风温度和炉料热装温度对铁前系统能耗的影响,并对不同条件下铁前系统各个工艺及全系统的物质流和能量流进行了分析。通过以上工作,本文得到了如下主要结论：(1)高炉炼铁环节能耗随着富氧率和鼓风温度的增加而降低,而随炉料热装温度的增加先下降后升高。受理论燃烧温度的限制,在富氧率为29%、鼓风温度为25℃,炉料热装温度为150℃条件下,高炉炼铁环节能耗相对其他条件下的更低,为375.77kgce/tHM。(2)当高炉炉料热装温度不变时,高炉的富氧率从0%增加到29%,导致高炉煤气成分发生变化,从而使焦化环节能耗平均降低1kgce/t焦炭,焦化加热煤气用量平均减小71m3/t焦炭；球团环节能耗平均降低4kgce/t球团矿,球团加热煤气用量平均减小68m3/t球团矿；而对烧结环节能耗和所用煤气量影响不大。(3)在高炉富氧率不变情况下,炉料装入高炉的温度增加,导致高炉顶部煤气温度升高,当煤气温度从25℃增加到800℃时,从而使焦化环节能耗平均降低3.5kgce/t焦炭,焦化加热煤气用量平均减小54m3/t焦炭；球团环节能耗平均降低3kgce/t球团矿,球团加热煤气用量平均减小44m3/t球团矿；而对烧结环节能耗和所用煤气量影响不大。(4)当高炉煤气氧化度为0.75时,得到了一种理论环节能耗最低的铁前系统工艺,该工艺条件是富氧率29%,鼓风温度25℃,炉料装入温度800℃,铁前系统环节能耗由原来的606.81kgce/tHM降为539.30kgce/tHM。(5)铁前系统新工艺与传统工艺相比,生产1t铁水,焦比从原来的371.3kg减小到291.4kg；直接回收炉料显热可达1.62GJ,并且炉料所带入的热量可以代替热风所带入的热量,从而达到全炉热平衡,另外除了铁前系统自身消耗0.4GJ的煤气,能够剩余煤气的物理热达到1.38GJ。更多还原

【Abstract】 Recycle of the sensible heat is not complete for the materials with medium and low temperatures during the traditional coking, sintering and pelletizing process, and the low energy utilization rate results in a lot of heat wasting. Therefore, oxygen blast furnace with continuous hot charging method is proposed, and the model of corresponding raw material preparing process is established to be solved for the optimal process parameters. The systematic model of ironmaking is on the basis of material and energy conversation principles, which includes blast furnace model, coking model, sintering model and pelletizing model respectively. The dependences of oxygen enrichment rate, blast temperature and charging temperature on energy consumption are studied, meanwhile, the material flow and energy flow of the ironmaking system are analyzed.According to the calculation results and relevant analyses, five conclusions are presented as follows:(1)The energy consumption of blast furnace process decrease with the oxygen enrichment rate and blast temperature increasing, while the value decrease to the minimum and then raising with the increase of hot charging temperature. Combination with the limitation of theoretical combustion temperature, the optimal operating parameters are oxygen enrichment rate of29%, blast temperature of25℃, and charging temperature of150℃respectively, which result in the lowest energy consumption of375.77kgce/tHM.(2)Provided that hot charging temperature is constant:when the oxygen enrichment rate changes from0%to29%which results in the changing of top gas composition of the blast furnace, accordingly, the average energy consumption of coking reduces by1kgce/t, and the average consumption of heating gas of coking reduces by71m3/t; the average energy consumption of pelletizing reduces by4kgce/t, and the average consumption of heating gas of pelletizing reduces by68m/t; however, the changes of oxygen enrichment have little influence on the energy consumption and gas utilization of sintering process.(3)Provided that the oxygen enrichment rate is consistent, top gas temperature goes up with the increasing of charging temperature. When the gas temperature changes from25℃to800℃, accordingly, the average energy consumption of coking reduces by3.5kgce/t, and the average consumption of heating gas of coking reduces by54m3/t; the average energy consumption of pelletizing reduces by3kgce/t, and the average consumption of heating gas of pelletizing reduces by44m3/t; however, the changes of charging temperature have little influence on the energy consumption and gas utilization of sintering process.(4) When the oxidation degree reaches the theoretical maximum value0.75, an series of optimal operating parameters are obtained in which the oxygen enrichment rate is29%, the blast temperature is25℃and the charging temperature is800℃respectively. Under these optimal conditions, the energy consumption of the whole ironmaking system reduces from606.81kgce/tHM to539.30kgce/tHM.(5) From the views of the systematic material flow and energy flow, comparisons between the traditional processes and the newly proposed processes are executed based on1ton hot metal. Coke rate reduces from371.3kg to291.4kg; The burden sensible heat of1.62GJ can be directly recycled which is required from the hot air in traditional processes. It can not only maintain the heat balance, but also reduce energy consumption in the hot blast stove process; In the newly proposed processes, top gas volume is sufficient for recycling in the inner system. Moreover, the surplus top gas with sensible heat of1.3GJ can be saved.更多还原