| The desulphurization technology of the pretreatment of the iron melt is the ordinary method in the metallurgy industry and is popular in the steel companies.The use of magnesium as a desulfurizing agent has the following advantages: first,the reaction of magnesium with sulfur is an exothermic reaction that provides heat for the desulfurization reaction;second,desulfurization reaction of magnesium sulfide excellent stability;at last,the reaction speed is faster,and the slag generated by the desulfurization reaction is less.So hot metal pretreatment desulfurization process often use magnesium as a desulfurizer.However,the use of magnesium as a desulfurizing agent also has some drawbacks,for example,the passivation of magnesium and magnesium produced by electrolytic magnesium oxide increases the cost of smelting and magnesium utilization is low,it needs to improve.Therefore,it is need to develop a new type of energy saving,environmental protection and efficient desulfurization agent for hot metal pretreatment desulfurization.Currently,a number of steel companies often use the complex injection the magnesium matrix desulphurization,which is the deactivated magnesium pellet added CaO,CaC2 and other additives,to deal with the sulfide which is in the iron melt.Therefore,it is ordinary to use the magnesium as the desulfurizer in the desulphurization technology.China is the country which has the most reserve of magnesite in the world.The amount of magnesite reserve,which is in the high grade of ore,is the most abundant in Liaoning province that has the most magnesite reserve,output and export volume in the world.In the thesis,use the new tape magnesite desulfurizer to desulfur itself at the high temperature.Than investigating the feasibility of electrolysis desulphurization reaction and the electrochemistry property of the new tape magnesite desulfurizer.New tape magnesite desulfurizer will produce complex ion to make the magnesium oxide fused at the temperature of the iron melt.Based on the self-electrolysis experiment of the new magnesite-based desulfurizer and the XRD analysis of the product,the conclusion is made that the desulphurization method of the new magnesite-based desulfurizer under the high temperature condition is feasible.Through the research of the basic property of electrochemistry and the mechanisation research of desulphurization reaction to analysis the reason of the temperature and current to influence the desulphurization reaction rate,desulphurization efficiency and operat ing factor.At the same time,the thesis uses the orthogonal experiment toanalysis the extent of temperature and current to influence the the desulphurization reaction rate,desulphurization efficiency and operating factor and the best combined condition in the desulphurization process.Through the one way experiment to explain the influence of the current and temperature to the process of desulphurization,the result could be getting that the desulphurization reaction rate will be increased with the current increased until a certain time when the temperature is a const.In the time,the rate will be temporary decreased.Then the rate will still be increased.And in the other situation,when the current is a const,the desulphurization reaction rate will be increased with the temperature increased.The best experiment condition analyzed is the 1400 degree Celsius and 1A current.At that time,the desulphurization reaction rate is 47.6%/min,the desulphurization efficiency is 62.6% and the operating factor of magnesium is 42.0%.The result of the thesis confirms the feasibility of the desulphurization technology which is using electrolysis to deoxidize the new type magnesite based to magnesium in a pretreatment of the iron melt at a high temperature.In addition,the result will have a significant meaning to the industrialization and technology optimization of the technology. |
PDF Full Text Request