Study Of The Temperature Drop And Energy Saving The Iron-Steel Interface

In the process of steel production,the iron-steel interface is an important section to produce the iron and steel.In recent years,researchers mainly focused on investigating the heat loss of a single process onthe iron-steel interface.However,these researches have not been integrated and systematic for the whole interface.Therefore,in the current study,in order to provide some useful support for the optimization and energy saving of the section,the process technology interface of the iron and steel section is selected for thermal state analysis.The research object is a torpedo ladle of 320 tons and a package of iron-clad.Commerical softwares,i.e.,Solidworks,ICEM,Fluent,were utilized to do the model construction,mesh division,and simulation calculation.Based on the thermal test data,the thermal state in each stage for different types of torpedo ladle is compared and analyzed.It provides corresponding theoretical and technical support for the research on the temperature drop and energy saving of molten iron on the iron-steel interface.For the baking stage:after baking,for the conventional torpedo ladle,the total heat storage capacity is about 8.94×104 MJ.The heat in working layer accounts for 84.02%of the total heat in the tank lining.On the basis of the conventional torpedo ladle,the permanent layer is modified with a layer of insulation palate,and the addition of nano-type insulation board or magnesium silicate-type insulation board can speed up the baking rate.The baking operation can be finished in 5 hours and 2 hours in advance.The surface temperature was reduced by about 57? and 41?,and the corresponding heat of the tank was increased by about 1.17×104 MJ and 0.34×104 MJ.For the iron-receiving stage:the macro trend of the temperature drop curve of molten iron is that molten iron first contacts the torpedo ladle,which leads to the temperature to drop rapidly.Then it gradually stabilizes,and finally rises steadly in a small amount.The addition of nano insulation board or magnesium silicate insulation board can increase the molten iron temperature to about 1.38? and 0.99?,and the corresponding total heat storage is increased by about 0.98×104 MJ and 0.30×104 MJ.Moreover,The heat loss of the molten iron caused by the heat storage is relatively reduced.For the transportation stage of heavy tank:the heat loss through truncated cone section,cylindrical section,trunnion section,and tank mouth,is 51.12%,35.03%,3.93%,and 9.92%,respectively.It can be found that the heat loss ratio of the truncated cone section is the largest.The addition of nano insulation board or magnesium silicate insulation board can make the molten iron temperature increase to about 3.12? and 2.06?,and the total heat storage is increased by about 0.97×104 MJ and 0.27×104MJ.Furthermore,the heat storage is decreased by approximately 0.10×103 MJ and 0.01×103 MJ,respectively.For the stationary stage of the heavy tank:the heat loss through truncated cone section,cylindrical section,trunnion section,and tank mouth,is about 47.73%,30.42%,6.63%,and 15.22%,respectively.The addition of nano-type insulation board or magnesium silicate insulation board can increase the temperature of molten iron to about 4.05? and 3.02?.The total heat storage is increased by about 0.97×104MJ and 0.28×104 MJ,and the corresponding heat storage is decreased by about 0.10×103 MJ and 0.20×103 MJ,respectively.For the empty tank stage:for a conventional torpedo ladle,the account of heat loss through the tank mouth and the shell account is about 52.11%and 47.89%.Compared with the conventional torpedo ladle without cover,the inner wall surface temperature for the nono board torpedo ladle and the magnesium board torpedo can be increased by about 54.97? and 20.36?,respectively.For the case with cover,adding the nano insulation board and magnesium silicate insulation board can increase the inner wall surface temperature byabout 48.46? and 23.30?.Compared with the improved torpedo ladle with the cover and the conventional torpedo ladle without the cover,the inner wall surface temperature was increased by 91.14? and 66.18?,respectively.For torpedo ladle without cover,The surface temperature of the shell is decreased by 59.92? and 42.67?.For torpedo ladle with cover,The surface temperature of the shell is decreased by 48.02? and 63.59?.The temperature drop of the molten iron is proportional to the temperature of the molten iron from the Blast furnace.For the temperature of the molten iron from the blast furnace about 1440?,1460?,1480?,1500? and 1520?,the temperature drop in the whold peocess is about 102.30?,105.64?,108.76?,112.43? and 115.61? respectively.When the initial molten iron temperature is higher,the initial baking temperature should be increased to decrease the heat loss of molten iron.The temperature of the molten iron in the return package of the magnesium silicate and torpedo ladle is higher than that of the conventional torpedo ladle.Compared with conventional return torpedo ladle,the temperature of molten iron can be increased by 5.62?for a magnesium silicate return torpedo ladle with cover.