采用DEM-CFD组合模型研究高炉炉身煤气喷吹时炉内气固流动的动力学行为  

Dynamic behavior of gas and solid flows in blast furnace with shaft gas injection by hybrid model of DEM-CFD

作　　者：Shigeru Ueda Shungo Natsui Ryo Inoue Tatsuro Ariyama 徐辉(译) 蔡宁(校) 

机构地区：[1]东北大学,多元物质科学研究所,日本仙台 [2]不详

出　　处：《世界钢铁》2013年第5期10-17,共8页World Iron & Steel

摘　　要：为减少钢铁厂CO2排放,必须降低焦比。现在高炉炉身喷吹还原气被认为可降低焦比。但炉身喷吹煤气的效果由其在高炉内的穿透性决定。解析高炉炉身喷吹煤气的行为,可有效评价其在实际高炉中的效果。采用DEM-CFD组合模型研究了高炉炉身喷吹煤气的气固流动力学行为。考虑到气固间相互作用,采用DEM模型模拟炉料的准确分布。根据模拟结果,喷吹煤气的流动行为受填充床的透气性制约,且气体的穿透效果被限定在特定区域。除喷吹风口区域外,炉身等压面近似为水平面。喷吹煤气的流速对其在高炉内的穿透性有一定影响。然而,喷吹煤气所占横截面的面积与常规风口和炉身附加风口煤气量的比值相对应。炉身煤气喷吹被认为是控制炉身热流比的有效方法,但其难以与上升气流立刻混合。根据期望目标,需慎重选择喷吹位置。该结果可应用于顶煤气循环等新工艺的设计。In order to mitigate CO2 emissions from steel works, decreasing coke rate are mandatory. The idea of reducing gas injection to the shaft of blast furnace has recently attracted special attention to decrease coke rate. However, the effect of shaft gas injection depends on the gas penetration in blast furnace. To evaluate the shaft gas injection in the actual blast furnace, the behavior of gas injected to the shaft must be clarified. In the present study, the dynamic behavior of gas and solid flows in the blast furnace with shaft gas injection was investigated by a hybrid model of DEM-CFD. The accurate burden distribution based on DEM was simulated considering the interaction between gas and solid flows. According to the simulation results, the gas flow of injected gas was suppressed by the permeability resistance in the packed bed, and the gas penetration effect was limited to the specified region. The iso- bar plane in the shaft level was nearly flat horizontally expect the region nearby the injection tuyere. The gas velocity of injection gas has a definite effect on the penetration to the blast furnace. However, the area of injection gas in the horizontal section was proportional to ratio of gas from the ordinary tuyere and additional tuyere at the shaft level. Totally, the shaft gas injection was considered to be a favorable method to control the thermal-flow ratio in the shaft, however, it was difficult to mix instantly the injection gas with upwards gas. The location of injection point must be cautiously selected by its purpose. These results were available for the design of new process such as top gas recycling.

关 键 词：炼铁 高炉 炉身喷吹 低还原剂操作 离散元法 计算流体力学 炉顶煤气循环 

分 类 号：TF06[冶金工程—冶金物理化学]