Influence of Thermal Stability of Quartz and the Particle Size Distribution of Burden Materials on the Process of Electrothermal Smelting of Metallurgical Silicon
The article describes the thermal stability of quartz deposits in Kazakhstan-Aktas and Sarykul. It is established that the quartz of the Aktas deposit is a raw material with low thermal stability, and quartz is of medium-durability at Sarykul deposit. The complex influence of the thermal stability of this raw material on the technological parameters of smelting of technical silicon under experimental industrial conditions of electrothermal melting in a furnace with a capacity of 30 MVA was studied at LLP “Tau-Ken-Temir” (Kazakhstan). A new method for optimizing the smelting of commercial silicon has been developed, even when using raw materials with low thermal stability. The main idea of the method is that the less thermally stable quartz is used, the more the initial size of its pieces should be. Optimum values of the average size of pieces of quartz-Aktas(85-95 mm) and Sarykul-(30-40 mm) are obtained.
INNOVATIVE ELECTRIC SMELTER SOLUTIONS OF THE SMS GROUP FOR THE SILICON INDUSTRY
As far back as 1906, the SMS group delivered the first submerged arc furnace. Meanwhile – over more than 100 years SMS has supplied more than 7,500 submerged arc furnace (SAF) plants as well as major components to SMS customers worldwide operating plants for the production of ferroalloys, silicon, non-ferrous metals and other applications. Metix as well as Paul Wurth which have recently joined the SMS group have significantly increased the SMS product portfolio for our clients and SMS now offers complete process lines for all metal production facilities including a full range of upstream and downstream equipment. This paper will focus on recent SMS developments and projects with respect to electric smelters and submerged arc furnace technology, in particular the production of silicon. The paper will present the recent technology for silicon smelters, which are currently in progress or which have been recently commissioned. Most electric furnaces are considered to be highly energy-intensive units. The high level of electrical energy required is to a large extent defined by the process but can also be influenced by the equipment and the operating practices. SMS has developed a number of measures to reduce the overall energy consumption of these metal production facilities and will meet the requirements on environmental restrictions of the future. INTRODUCTION TO THE SMS GROUP The SMS group is, under SMS Holding GmbH, a global player in plant construction and mechanical engineering for the steel, nonferrous metals, ferroalloy and silicon production industries. It consists of the business areas represented by SMS Siemag, SMS Meer, Paul Wurth and the industrial affiliates. SMS Siemag is a part of the SMS group with more than 13,500 employees, which in 2013 attracted sales totaling some EUR 3 billion. Silicon furnaces are designed in the SMS office in Düsseldorf, Germany [1]. In recent decades SMS Siemag has supplied the majority of the SAF’s for FeSi & silicon production. With more than 90 references for large scale silicon and FeSi furnaces since 1970, SMS is leading the furnace market (see Fig. 1). Fig. 1: SMS Siemag milestones in Silicon / FeSi furnaces Over the past years silicon plants have been commissioned in Korea, China, Kazakhstan and Germany. The most recent reference is a FeSi plant supplied for POSCO in Korea. The following Figure 1 shows a selection of the furnaces installed with the involvement of the SMS group. On 22 nd June 2011 the Metix Company which is based in Johannesburg, RSA, joined SMS Siemag AG as part of the SMS Group. Providing active in-plant construction and supplying
Status Report on Pyrometallurgical Ferronickel Production
Murin Murin from Anaconda Nickel, supported by Glencor and Anglo America is trying to produce nickel with a pressurized acid leaching process (HPAL) at industrial scale. It has been reported that the availability of the plant is low, and the expected cost advantages at the industrial level have not yet been reached. The original production cost was estimated to be less than 2 US $/lb. Currently, the plant produces nickel for 4 to 5 US $/lb. The companies' forecast is still positive, even if the original goals for investment and operating cost have not been achieved. /2/