顶底复吹条件下不锈钢VOD精炼过程的数学模拟——过程数学模型  

Mathematical Modeling of VOD Refining Process of Stainless Steel under Conditions of Combined Top and Bottom Blowing——Mathematical Model of the Process

作　　者：魏季和[1] 李毅[1] 

机构地区：[1]上海大学材料科学与工程学院,上海200072

出　　处：《太原理工大学学报》2014年第1期1-9,共9页Journal of Taiyuan University of Technology

基　　金：国家自然科学基金和宝山钢铁公司联合资助项目(50374074)

摘　　要：对顶底复吹条件下不锈钢VOD精炼过程提出了一个数学模型。该模型假设低压下顶吹入的氧,部分与逸出熔池的CO反应,部分使生成的钢液滴内各元素氧化,其余经射流冲击坑向钢液渗透和溶解;进入熔池的氧使钢中的碳、铬、硅、锰和铁氧化,生成的FeO是一中间产物。所有可能的氧化-还原反应分别在钢液/熔渣及钢液/气泡界面同时发生,并在竞争中达到其各自的综合平衡。在较高碳含量下,各元素氧化速率主要与吹氧量有关;在低碳含量下,脱碳速率主要取决于钢中碳的传质。吹入钢液未反应的氧不在钢中溶解和积聚,逸出熔池并参与熔池上方炉气内CO的二次燃烧。以多层复合壁的二维瞬态导热处理了炉壁传热,考虑了各操作因素及不等温状态等的影响。A mathematical model for the whole VOD refining process of stainless steel under the conditons of combined top and bottom blowing was proposed and developed. The model is based on the assumptions that one part of the oxygen blown through a top lance at reduced pressure reacts with CO escaped from the bath, another part of the oxygen oxidizes the elements in the molten steel droplets splashed by the jet, and the remaining penetrates and dissolves into the molten steel through the cavity impacted by the jet. The oxygen entering into the bath oxidizes C, Cr, Si, Mn in the steel and Fe as a matrix, but the FeO formed is an intermediate product. In the combined blowing process, all the possible oxidation-reduction reactions take place simultaneously and reach their combined equilib- ria separately in competition at the liquid/slag and liquid/bubble interfaces. In the Ar stirring period after the top blowing operation is over, the possible reactions occur simultaneously and reach a combined equilibrium in competition at the liquid/bubble interfaces. The overall decarburization rate in the refining process is the sum of the contributions of both the top and bottom blowing processes. At higher carbon contents, the oxidation rates of elements are mainly related to the supplied oxygen rate, and at low carbon concentrations, the rate of decarburization is primarily dependent on the mass transfer of carbon in the molten steel. The un-reacted oxygen blown into the bath does not dissolve and accumulate in the steel but escapes from the bath and takes part in the post-combustion of CO in the ex- shuat gas. The heat transfer of the vessel was treated in terms of the two-dimensional transient heat- conduction probelms of composite multilayer walls,taking into account the influence of the operationl factors, the non-isothermal conditions and others.

关 键 词：不锈钢 VOD精炼 顶底复吹过程 数学模拟 

分 类 号：TF72[冶金工程—钢铁冶金]