Alumina and Alumina Refractories...

Alumina and Alumina Refractories Alumina (Al2O3) refractories are the part of alumina- silica (SiO2) group of refractories and belongs to the SiO2 -Al2O3 phase equilibrium system as shown in diagram at Fig 1. They differs from fire clay refractories in term of Al2O3 content and normally have Al2O3 content of more than 45 %. The raw material base for these refractories are different than the fire clay bricks. Fig 1 SiO2 – Al2O3 phase diagram As seen in the diagram, refractoriness increases with the increase in the Al2O3 content. The eutectic at 1595 deg C has a composition of 94.5 % SiO2 and 5.5 % Al2O3. As the Al2O3 content is increased, the melting point of the refractory increases to a maximum of 2054 deg C which is the melting point of pure corundum. The only stable compound in the system is mullite, which has a defective space lattice and decomposes into corundum and liquid phase at around 1840 deg C. The classification of Al2O3-SiO2 refractories as per the Al2O3–SiO2 phase equilibrium diagram is given in Tab 1. Tab 1 Classification of Al2O3-SiO2 refractories as per the Al2O3–SiO2 phase equilibrium diagram Range of Al2O3  Phases as per common terminology General performance of refractories in conditions of the absence of slag corrosion or alkali attack Al2O3 less than 50 % Fireclay (Chamotte); Phases on phase diagram are mullite and glass; can contain free SiO2 Normally made from 100 % fireclay, Highest quality grades (super duty bricks) usable to about 1600 deg C,  Usually contain 38 % to 42 % Al2O3 and are based on fireclay minerals Al2O3 50 % or 60 % Sillimanite, andalusite, or kyanite; Phases on phase diagram are mullite as major phase and glass as minor phase; can contain free SiO2 These...

Managing Partnerships for Organizational Excellence...

Managing Partnerships for Organizational Excellence A partnership is a working relationship between two or more parties creating added value for the customer. It is defined as a relationship in which two or more parties, having compatible goals, form an agreement to share the work, share the risk and share the results or proceeds. It is a collaborative relationship between entities to work toward shared objectives through a mutually agreed division of work. It is the building of a sustainable relationship between the parties based on mutual trust, respect and openness. Excellent organization plans and manage external partnerships, suppliers and internal resources in order to support strategy and policies and the effective operation of its processes. They ensure that they effectively manage their environmental and societal impact. Strong partnerships enable organizations to do more than what they can do alone, become more diverse and innovative in their thinking and have the potential to reach a far wider audience. By sharing expertise, resources, and stakeholders, organizations that partner successfully are able to access new markets, spur innovation, and achieve greater outcomes. Entering into a partnership helps the organization with some added value that it cannot achieve in any other way even with the outlay in time, money and materials. Typical benefits can include reduction in time to market, first to market with new technology and reduction in costs. Partnership can avoid duplication of efforts, provide for pooling of scarce resources, and promote coordinated, focused and consistent mutual efforts toward achievement of organizational success as well as in the bottom line. A partnership  can be a handshake (not a handout) with a written agreement between the parties with appropriate legal authority. It needs fairly equal participation of the partners and is to be consistent with the plans, policies...

Instrument Analysis of Steel, Slag and Raw Materials Jan25

Instrument Analysis of Steel, Slag and Raw Materials...

Instrument Analysis of Steel, Slag and Raw Materials Instrument analysis is widely used for the qualitative and quantitative elemental analysis of raw materials, iron (hot metal), steel, slag, refractories, and sludges samples. Compared to the wet analysis, the advantage of instrument analysis is that it is cost effective and multi elemental besides being very fast. The worries caused by interfering elements in the wet chemical analysis are eliminated. Instrument analysis avoids the need of waiting several hours for certain elements, which is a necessity when the wet chemical methods are employed. Furthermore, instrument analysis provides a fairly uniform detection limit across a large list of elements or compounds and is applicable to a wide range of concentrations, ranging from 100 % to few parts per million (ppm). The instrumental methods are reproducible with lesser scope of human error because of lesser human intervention. They are rugged, reliable and accurate with the accuracy depends upon the calibration and the standards used for the calibration. The analysis of steel, slag and raw materials is important and essential not only during steel making process for the purpose of control but also for the large number of samples needed to be analyzed for various other purposes. The information from an analysis is useful for various purposes, such as the inspection of raw materials, intermediate product and end product, environmental assessment, process control, failure analysis, quality control of the products and for the purpose of research and development. History While the spectrograph had been used for quite some time in other fields, the first instrument to be used successfully for ferrous melting control was installed in a foundry in 1935. A Baird Spectrograph was installed in the Timken laboratory in 1943 for the analysis of tests from the melt...

Magnesia

Magnesia Magnesia or magnesium oxide (MgO) is a white hygroscopic solid mineral that occurs naturally as periclase. It forms magnesium hydroxide in the presence of water [MgO + H2O = Mg(OH)2], but this reaction can be reversed by heating magnesium hydroxide to separate moisture. Magnesium (Mg) is the eighth most abundant element and constitutes about 2 percent of the crust of the earth. It is the third most plentiful element dissolved in seawater, with a concentration averaging 0.13 %. Although magnesium is found in over 60 minerals, only dolomite, magnesite, brucite, carnallite, and olivine are of commercial importance. Magnesium and magnesium compounds are produced from seawater, well and lake brines and bitterns, as well as from the above mentioned minerals. Magnesite (MgCO3), the naturally occurring carbonate of magnesium (Mg) is one of the key natural sources for the production of magnesia (MgO) and subsequently fused magnesia. It is the world’s  largest source of magnesia. It contains a theoretical maximum magnesia content of 47.6 %. It occurs in two distinct physical forms namely (i)  macro-crystalline and (ii) crypto-crystalline. Crypto-crystalline magnesite is generally of a higher purity than macro-crystalline ore, but tends to occur in smaller deposits than the macro-crystalline form. The word magnesite literally refers only to the natural mineral, but common usage applies this name to three other types of materials, dead burned magnesia (DBM), electro fused magnesia and calcined magnesia also called caustic calcined magnesia. Often magnesia word is replaced by magnesite in these products. These products of magnesite often differ mainly in density and crystal development that results from different levels of heat application. The three products of magnesite are shown in Fig 1. Fig 1 Products of magnesite  Magnesia is an alkaline earth metal oxide. Magnesium oxide is normally produced by the calcinations of...

Leading with Vision, Inspiration and Integrity for Excellence...

Leading with Vision, Inspiration and Integrity for Excellence An organization which aspires for excellence has leaders  in the management team who not only shape the future but also make it happen by acting as role models for its values and ethics. The leaders have capabilities  and integrity to inspire, adapt, react and gain the commitment of all the stakeholders. They are flexible, enabling the organization to anticipate and react in a timely manner to ensure and sustain the ongoing success of the organization. Organizational leaders develop the mission, vision, values and ethics and act as role models. They define, monitor, review and drive the improvement of the organizational management system and performance. They  engage with external stakeholders and reinforce a culture of excellence with the organizational people. They ensure that the organisation is flexible and manages change effectively. People like working with organizational leaders who do two things namely (i) lead from their values, and (ii) share an inspiring vision for the future. These two things are clearly connected. If the organizational leaders are grounded in their values, they can build a culture of trust and transparency in the organization. The three basic requirements for the organizational leaders for propelling the organization on the path of excellence are namely (i) vision, (ii) inspiration and (iii) integrity. These three basic requirements are shown in Fig 1 and described below. Fig 1 Basic requirements for organizational leadership Vision  Organizational leaders are to dream, create and articulate a wonderful, compelling and inspiring vision for the future of the organization. The vision is to reflect a new dawn for the organization and is to be created  working with imagination, insight, and boldness. It must present a challenge that calls forth the best in people and brings them together around a...