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Coal and energy consumption in the COREX process can be minimised from the balance between the required and generated reduction gas. Metallisation ratio is calculated at the balance, which corresponds to the effective calorific value of smelting coal. The proper metallisation ratio will be defined in this paper, after which it is demonstrated that an effective calorific value of smelting coal is needed to minimise the consumption of energy in the process. In addition, heat stability is also an important parameter when using coal instead of coke to insure a useful fixed bed in the melter gasifier. By considering the above points the energy consumption in the COREX process can be optimised. [ABSTRACT FROM AUTHOR]

The existing industrial electrolytic steel pickling process is only 30% current efficient. Use of approximate modelling of the process and solution of the model predicts that inter-electrode insulation improves the current and energy efficiency, and this paper describes the experimental work that has validated this prediction. Some of the main results are: (a) the current efficiency varied from 20% without insulation to 100% with complete insulation, (b) the use of just partial insulations yielded a significant improvement in the process efficiency and at the same time maintained good electrolyte mixing and homogeneity which can not be attained with complete insulation. The theoretical foundations of this method and its various consequences are discussed. The method is relatively easy to apply to existing industrial electrolytic pickling tanks, and also provides system control flexibility for optimal pickling of different steel grades. The method's application cost is relatively low and saves investment in new equipment if a retrofit of an existing system is desired. [ABSTRACT FROM AUTHOR]

An innovative process of preparing ironmaking burden – the composite agglomeration process (CAP) has been developed. In CAP, part or all of the fine grained iron bearing materials are separately made into 8–16 mm diameter green pellets in a balling disc or drum, and the rest of fine grained and all of the coarse grained materials are granulated after first mixing with return fines, fuels and fluxes. The two granular materials are then subject to a secondary mixing, and the secondary mixture is charged onto the sintering strand. After ignition, sintering and cooling, the mixture is made into a composite agglomerate in which acid pellets are embedded in basic sinter. Investigation shows that the new process has a series of advantages over traditional sintering or pelletising such as ability to use diverse iron bearing materials, significant improvement in the material bed permeability and productivity of sintering machine, low energy consumption, and ability to prepare a low basicity charge with good metallurgical performance. Additionally, the use of the composite agglomerates in blast furnaces is capable of obviating the influence of the differences in quality of sinter and pellets on the operation. The new process has successfully been put into production in China. [ABSTRACT FROM AUTHOR]

The evaluation of energy consumption is of fundamental interest in the steelmaking process, especially in the industrial context strongly based on electric arc furnace (EAF) technology as in Italy. A correct analysis of energy exploitation is important to allow better control of the melting and refining period, but nowadays is insufficient. A modern and more precise analysis of the steelmaking process needs the evaluation of scrap oxidation, the balance between the exploited electric and the chemical energies and an exergetic analysis which describes the quality of the energy exploitation and which can provide useful information on the environmental impact. This research has been dedicated to structure a tool to describe the system comprising the furnace, the liquid steel and the charged scrap during its evolution when melting and refining. The computational model has been designed and validated on 40 t EAF that belongs to ASO, a steelmaking company in the north of Italy. [ABSTRACT FROM AUTHOR]

Improved knowledge of the effect of scrap grades on the electric steelmaking process and optimised scrap loading practices increase the potential for process automation. As part of an ongoing programme, process data from four Scandinavian EAFs have been analysed, using the multivariate process monitoring approach, to develop predictive models for end point conditions such as chemical composition, yield and energy consumption. The models developed generally predict final Cr, Ni and Mo and tramp element contents well, but electrical energy consumption, yield and content of oxidisable and impurity elements (C, Si, Mn, P, S) are at present more difficult to predict. Potential scrap management applications of the prediction models are also presented. [ABSTRACT FROM AUTHOR]

It is well known that steel is the backbone of our built environment. Steel based buildings can be refurbished, steel components can be reused, and at the end of its life steel can be completely recycled back to new metal with no loss of properties. In fact it is part of a system with a number of options to recirculate products and provide innovative solutions. In a changing market where clients increasingly value the whole life cost of their investments over the initial capital cost there is a new opportunity for steel-based construction. The underlying benefits of steel in sustainable construction are described, employing examples ranging from steel in structural frames through the increased use of off-site manufacturing to a demonstration of what is possible if existing technologies are combined to produce buildings that are quick to build, are adaptable in use, are energy efficient, are comfortable to live in and are constructed with reusability and recyclability in mind. In conclusion, a number of observations are made on the practical things that steel can contribute to increasing the quality and sustainability of our built environment. [ABSTRACT FROM AUTHOR]

Comments on the continued development of the electric arc furnace. Increase in scrap material costs; Continuing drive to energy efficient steelmaking; Use of modern electric arc furnaces; Monitoring of electrode consumption; Standard arc furnace operation.