Refractories and Classification of Refractories...

Refractories and Classification of Refractories Refractories are inorganic, nonmetallic, porous and heterogeneous materials composed of thermally stable mineral aggregates, a binder phase and additives. The principal raw materials used in the production of refractories are normally the oxides of silicon, aluminum, magnesium, calcium and zirconium. There are some non-oxide refractories like carbides, nitrides, borides, silicates and graphite. Refractories are chosen according to the conditions they face during their use. Some applications require special refractory materials. Zirconia is used when the material is required to withstand extremely high temperatures. Silicon carbide and carbon are two other refractory materials used in some very severe temperature conditions, but they cannot be used in contact with oxygen, since they oxidize and burn in atmospheres containing oxygen. Refractories are the materials which are resistant to heat and exposure to different degrees of mechanical stress and strain, thermal stress and strain, corrosion/erosion from solids, liquids and gases, gas diffusion, and mechanical abrasion at various temperatures. In simplified language, they are considered to be materials of construction which are able to withstand high temperatures. Refractories are usually inorganic non-metallic materials with refractoriness greater than 1500 deg C. They belong to coarse-grained ceramics having microstructure which is composed of large grains. The basis of body is coarse-grained grog joined by fine materials. Refractory products are a specific sort of ceramics that differs from any ‘normal’ ceramics mainly with their coarse-grained structure being formed by larger grog particles joined by finer intermediate materials (bonding). ASTM C71 defines refractories as ‘non-metallic materials having those chemical and physical properties that make them applicable for structures or as components of systems that are exposed to environments above 538 deg C’. Refractories are to be chemically and physically stable at high temperatures. Depending on the operating environment, they...

Role and Responsibilities of Project Manager in a Steel Project...

Role and Responsibilities of Project Manager in a Steel Project A project manager is usually a person who has the overall responsibility of managing a project successfully during its various stages in its life cycle consisting of initiation, planning, design, execution, monitoring, controlling, and closure. Because of the vastness of a steel project, there are several project managers in a steel project each having responsibility of an area of the project. A project manager is normally a person who keeps all the elements of a project together. Project manager is the ‘man in-charge’ of the project and is required to take responsibility as the project leader. Project manager reports to the management of the steel project and is responsible for the project progress to the management. The job of the project manager includes appraising the steel project management timely all the issues concerning the projects through a well laid out reporting system. The project manager is to run all the affairs of the project during its life cycle and is responsible to complete the project successfully utilizing the authority delegated to him by the steel project management. Project manager is to operate within the triple constraints of the project which are time, resources, and quality. The role of the project manager encompasses several activities which include the following. Complete planning for the project. Sequencing of project activities and creating an environment which is conducive to produce results. Developing of an efficient, honest, and motivated team of employees which works hard for achieving the objectives of the project. Developing budgets for getting finances from the steel project management to fund the expenditures needed for the project. Management of available resources in an efficient manner. Developing schedules for different stages of the project and management of...

Tecnored Process for Ironmaking Apr30

Tecnored Process for Ironmaking...

Tecnored Process for Ironmaking Tecnored process was developed by ‘Tecnored Desenvolvimento Tecnológico S.A.’ of Brazil and is based upon a low pressure moving bed reduction furnace which reduces cold bonded, carbon bearing, self-fluxing, and self-reducing pellets. Reduction is carried out in a short height shaft furnace of distinct design at typical reduction temperatures. The process produces hot metal (liquid iron). Tecnored technology has been conceived and developed to be a ‘coke-less’ ironmaking process, thus avoiding the investment and operation of environmentally harmful  coke ovens besides significantly reducing green-house gas emissions in the production of hot metal. Tecnored process uses a combination of hot and cold blast and requires no additional oxygen. It eliminates the need for coke plants, sinter plants, and tonnage oxygen plants. Hence, the process has much lower operating and investment costs than those of traditional ironmaking routes. Tecnored process is flexible with regard to the type of iron bearing and carbon bearing raw materials which it can process. The ability of the process to smelt either pellets or briquettes, or even mixed charges of both, provides means of using a wide range of alternative feed materials. The process has got good productivity and high energy efficiency. Tecnored process is also being claimed to be suitable for producing ferro alloys such as ferro manganese. History of development The history of the development of the Tecnored process comprises different phases with different goals, testing a wide range of raw materials and using distinct sizes and concepts of the reactor. During the period 1979 to 1985, development activities were carried out regarding the use of pyrite cinder containing self-reducing pellets as metallic burden in cupola furnaces. This concept of self-reduction was adapted to develop the new process.  In 1985 the concept of the Tecnored...

Environmental Impact Assessment and Environmental Management Plan for a Steel Project...

Environmental Impact Assessment and Environmental Management Plan for a Steel Project The environment clearance (EC) process for a steel project (Fig 1) has the following built in steps. These steps are (i) screening, (ii) scoping and consideration of alternatives, (iii) baseline data collection, (iv) impact prediction, (v) assessment of alternatives, description of mitigation measures and environmental impact statement, (vi) public hearing, (vii) environment management plan, (viii) decision making, (ix) monitoring of the clearance conditions. Fig 1 Process for obtaining environment clearance for a steel project The environmental impact assessment (EIA) and environmental management plan (EMP) is part of EC process. EIA and EMP is normally necessary for obtaining EC for (i) those projects which can significantly alter the landscape, land use pattern and lead to concentration of working and service population, (ii) those projects which need upstream development activity like assured supply of mineral products supply or downstream industrial process development, (iii) those projects which involve manufacture, handling and use of hazardous materials, and (iv) those projects which are located near ecologically sensitive areas, urban centres, hill resorts, and places of scientific and religious importance. For obtaining EC for the steel project, it is essential that a report covering the EIA and EMP) is submitted to the regulatory authorities. This report assists the process of decision making with regards to the EC for the project. In addition to getting EC for the project, the purpose of the EIA and EMP report is to take into account the environmental aspects of the project not only during its implementation but also after its commissioning. The purpose of EIA is to identify and evaluate the potential impacts (beneficial and adverse) of the steel project on the environmental system. It is a useful tool for decision making based...

Design and Engineering for Steel Project...

Design and Engineering for Steel Project Design and engineering activities are most critical for a steel project. They start at the time of the initiation of the project and continue for the whole life cycle of the project i.e. till the project is completed and handed over for operation. Further, nature of the design and engineering activities undergo changes as the steel project moves forward on its path of progress. Design and engineering consists of the task of translating a set of functional requirements of the project into a full set of specifications and drawings providing the details needed. It involves a variety of special fields which include (i) process engineering, (ii) civil engineering, (iii) structural engineering, (iv) mechanical engineering, (v) electrical engineering, (vi) fluid engineering, (vii) instrumentation and control engineering, (viii) automation and control activities, (ix) geo-technical engineering, and (x) environmental and safety engineering etc. In a steel project, whether it is a green field or a brown field, design and engineering is the most essential activity, since no other activity can take place without it. In fact, all the project activities have very high dependence on the design and engineering. As an example, the plant and equipment are procured based on technical specifications determined during project engineering. Similarly the erection of plant and equipment is carried out as per erection drawings. During design and engineering, it is necessary to take regulatory authorities approval on certain categories of drawing and documents. These approvals are to be taken well in time so that further engineering work can proceed without fear of it becoming redundant in case the regulatory authorities seek major modification of drawing and documents before according the approval. During design and engineering, a very large amount of information is handled. The type...