The Comparison of Two Calculation Methods of Billets Heating in Furnaces with the Help of Zone and FVM Methods

The comparison of two modelling methods for radiation heat exchange – finite volume and zonal methods – has been provided. The mathematical model of heating concast bars ring furnace has been created. Modelling of different heat modes of this furnace has been completed. In the result of modelling, it is shown that these methods demonstrate similar accuracy of obtained temperature values (not exceeding 50∘C). The calculation time of FVM method is greater than zonal method to 13%, because recalculations of absorption coefficients by EWBM method is needed. Keywords: radiation transfer, mathematical modeling, zonal method, discrete transfer zonal metho

View factors for surface zones

Methods of calculating view factors with different surface configurations are compared. A simple approach is proposed for estimating the error in calculating the view factors. An algorithm is formulated for selection of the method and the number of points of integration prior to the calculation. The algorithm significantly reduces the computation time by minimizing the number of integration points required, without loss of precision. © 2013 Allerton Press, Inc

Modeling of Metallurgical Process of Copper Fire Refining

The refining of blister copper is based on the partial removal of impurities that have an increased affinity for oxygen. The most interesting is the process of centralized copper refining at one plant. This is because blister copper from the producer plants has a different chemical composition. Obviously, the batch of each loading also has a variable chemical composition. Therefore, for a constantly changing averageweighted composition of a liquid metal, a different amount of oxygen is required to oxidize and slag the impurities. The aim of the work is the method of creating a mathematical model for solving the single-criterion and multicriteria task of firerefining of copper. Algorithms of the model based on the passive experiment are presented, with the chosen assumptions and limitations. Mathematical models are developed using correlation regression analysis. The resultant variable in the models is the concentration of oxygen in the melt. The objective function is determined by the main variables of the refining process. The results of mathematical modeling allow us to quickly calculate the concentration of oxygen supplied in the air composition into the melt of a batch of different chemical composition for the oxidation of impurities. The models are consistent with the general theory of anode melting, and can be used to control and predict the process. Keywords: fire refining, blister copper, impurity oxidation, mathematical model, linear regressio

Simulation of the solidification of the melt in the Vanyukov furnace in the case of emergency stoppage

A mathematical model of the Vanyukov furnace, which makes it possible to predict the behavior of an object in the emergency operational mode (upon the disconnection of the oxygen supply) and develop an effective system of additional heating which damps the consequences of the emergency mode and lowers the costs for the renovation of the furnace operation, is created. It is shown how solidification upon cooling the furnace with time is simulated using the enthalpy and porosity method. The mathematical model is adopted for existing production conditions, which are weakly defined. The energy characteristics of the mode for the solidifying furnace bath, which ensures its holding for a long time in the ready state to rapid firing, are found. Thus, the problem of excessively expensive furnace firing after prolonged production stoppage is solved in the conjugated statement with a calculation of the heating system of the overbath space. © 2013 Allerton Press, Inc

Improving the thermal characteristics of furnaces and the operating conditions of the lining by improving direct-flame-impingement methods for intensifying the heating of metal

This article discusses Russian research and development of the direct-flame-impingement method of heating and modifications made to this technology abroad in the form of the DFI and Oxy-fuel heating systems. It examines the advantages of these heating methods, especially the sharp reduction in refractories use and the substantial improvement in the service conditions of the furnace lining. Various designs of direct-flame-impingement heating furnaces are presented and aspects of their thermal performance are discussed. It is shown that the thermal efficiency of modern furnaces which employ direct flame heating can reach 65% and that emissions of nitrogen oxides from these units do not exceed 30 ppm even when the combustion air is preheated. The efficiency of using oxygen in natural-gas-fired heating furnaces is evaluated for different natural-gas prices. Relations are obtained to describe the effect of the degree of oxygen enrichment of the combustion air on the consumption of natural gas and oxygen individually and the consumption of natural gas + oxygen. The cost-effectiveness of using gas-oxygen burners in melting furnaces is also examined. © 2013 Springer Science+Business Media New York

BAT According to Climatic Neutrality of Production of Steel Products

The purpose of this article is to estimate the best available technologies for values of the following technological numbers: fuel, ecological, depreciation, greenhouse and their sums. All these numbers have power dimension: t of conditional fuel/unit of production that allows to put them. The fuel technological number characterizes power consumption of production. The technological ecological number transfers a payment of the enterprise for environmental pollution to power units. The technological depreciation number transfers depreciation charges from rubles to power units. The technological greenhouse number translates a payment of the enterprise for emissions of greenhouse gases in power units. Technological numbers have through character – from extraction of raw materials before receiving finished goods. The best available technologies are characterized by the smallest sum of all technological numbers. Keywords: through power-ecological analysis, power ecological capacity of production of steel products, technological fuel ecological greenhouse number, best available technologies, climatic neutralit

Graph model for carbon dioxide emissions from metallurgical plants

Mathematical models are presented for estimating carbon dioxide emissions from metallurgical processes. The article also presents a new mathematical model in graph form to calculate transit and net emissions of carbon dioxide based on the estimates obtained for the individual processes. The graph model is used to compare the blast-furnace-converter process with the blast-furnace-EAF process. © 2013 Springer Science+Business Media New York

Calculation of power consumption and issue of CO2 at various processes by the production of steel

Проведены сравнительные расчеты эмиссии диоксида углерода – парникового газа – при различных сочетаниях коксовых (доменная печь + конвертер, доменная печь + электродуговая печь или ЭДП) и бескоксовых (HyL-3 + ЭДП, MIDREX + ЭДП, ROMELT + ЭДП, COREX + ЭДП, ЭДП на ломе) процессов производства стали. Для сравнительной оценки технологических процессов приведено ранжирование по значению сквозной интегральной эмиссии парникового газа CO2. При производстве стали выявлены преимущества по значению эмиссии CO2 для процессов HyL-3 + ЭДП, Midrex + ЭДП.Comparative calculations of carbon dioxide emission - greenhouse gas at various combinations coke oven (a blast furnace – the converter, a blast furnace - the electric arc furnace or EAF) and the coke-free (HyL-3-EAF, MIDREX-EAF, ROMELT-EAF, COREX-EAF, EAF on scrap) processes for the production of steel are carried out. For comparative assessment of technological processes in the framework of the power-ecological analysis it is considered parameter of emission of CO2 greenhouse gas. Steel production advantages CO2 emissions when using processes of HyL-3 + EAF, Midrex + EAF are revealed