Noble ferroalloys

Noble ferroalloys Ferroalloys are a group of materials which are alloys of iron that contain a high percentage of one or more non ferrous metals as alloying elements. These alloys are used for the addition of these other elements into liquid metal. They are normally used as addition agents. More than 85 % of ferroalloys produced are used primarily in the manufacture of steel. Ferroalloys are usually classified into two main categories namely (i) bulk ferroalloys and (ii) noble or special ferroalloys. Noble ferroalloys are of high value and consumed in low proportions. These ferroalloys are one of the vital inputs required for the production of special types of steels and are used as additive inputs especially in the production of alloy and special steels. Noble ferroalloys (Fig 1) are ferro nickel (Fe-Ni), ferro molybdenum (Fe-Mo), ferro vanadium (Fe-V), ferro  tungsten (Fe-W), ferro niobium (Fe-Nb), ferro titanium (Fe-Ti), ferro aluminum (Fe-Al), ferro boron (Fe-B). There are some noble ferroalloys which are having more than one non ferrous metal as alloying elements. Examples are ferro silico magnesium (Fe-Si-Mg), ferro silico zirconium (Fe-Si-Zr), ferro nickel magnesium (Fe-Ni-Mg) etc. Fig 1 Noble Ferroalloys Ferro nickel Fe-Ni is used for alloying in the production of stainless and construction steels. Laterite ore is the main raw material for the production of Fe-Ni. Laterite ore is characterized by a relatively low nickel content and a high moisture content together with chemically bound water in the form of hydroxide. Typical laterite ore contains 1 % to 3 % Ni and a moisture content of 5 % to 10 %. Besides laterite ore, coke and/or coal is needed as a reducing agent, since Fe-Ni production takes place by a carbothermic process. Fe-Ni can also be produced from secondary raw materials, such as...

Stores Management

Stores Management Store is an important component of material management since it is a place that keeps the materials in a way by which the materials are well accounted for, are maintained safe, and are available at  the time of requirement. Storage is an essential and most vital part of the economic cycle and store management is a specialized function, which can contribute significantly to the overall efficiency and effectiveness of the materials function. Literally store refers to the place where materials are kept under custody. Typically a store has a few processes and a space for storage. The main processes (Fig 1) of  store are (i) to receive the incoming materials (receiving), (ii) to keep the materials as long as they are required for use (keeping in custody), and  (iii) to move them out of store for use (issuing). The auxiliary process of store is the stock control also known as inventory control. In a manufacturing organization, this process of receiving, keeping in custody, and issuing forms a cyclic process which runs on a continuous basis. The organizational set up of the store depends upon the requirements of the organization and is to be tailor made to meet the specific needs of the organization. Fig 1 Main processes of a store Store is to follow certain activities which are managed through use of various resources. Store management is concerned with ensuring that all the activities involved in storekeeping and stock control are carried out efficiently and economically by the store personnel. In many cases this also encompasses the recruitment, selection, induction and the training of store personnel, and much more. The basic responsibilities of store are to act as custodian and controlling agent for the materials to be stored, and to provide service to users...

Processes for Beneficiation of Iron Ores Mar28

Processes for Beneficiation of Iron Ores...

Processes for Beneficiation of Iron Ores  Iron is an abundant element in the earth’s crust averaging from 2 % to 3 % in sedimentary rocks to 8.5 % in basalt and gabbro. Because iron is present in many areas, it is of relatively low value and thus a deposit must have a high percentage of metal to be considered ore grade. Typically, a deposit must contain at least 25 % iron to be considered economically recoverable. Over 300 minerals contain iron but five minerals are the primary sources of iron ore. They are (i) magnetite (Fe3O4), (ii) hematite (Fe2O3), (iii) goethite (Fe2O3.H2O),  (iv) siderite (FeCO3), and (v) pyrite (FeS2). Mining of iron ores requires drilling, blasting, crushing, screening, and blending of the ores. Crushing and screening are an integral part of ore producing facilities. Crushing usually involves a primary crusher and secondary crushers operating in closed circuit with vibrating screens. Equipment selection is determined largely by the friability of the ore. Most of the screening operations on high grade ores are dry except when the fines fraction can be effectively upgraded by desliming. Iron ores normally fall within one of the three categories namely (i) direct shipping, or high grade ores, which contain enough iron to be charged to the iron making furnace directly and may only require crushing, screening, and blending, (ii) associated low grade merchant ores which occur around the high grade ores that can be mined concurrently and which require minor upgrading by washing to increase their iron content, (iii) low grade ores that requires extensive crushing, grinding and concentration to produce an acceptable concentrate. The iron ores that fall within these three categories have quite different processing requirements. To obtain a uniform product, ores of different grades, compositions, and sizes...

Bulk Ferroalloys

Bulk Ferroalloys  Ferroalloys are a group of materials which are alloys of iron that contain a high percentage of one or more non ferrous metals as alloying elements. These alloys are used for the addition of these other elements into liquid metal. They are normally used as addition agents. More than 85 % of ferroalloys produced are used primarily in the manufacture of steel. Ferroalloys are used as master alloys in steel making, alloying of steels, for the production of stainless steels, and in iron or steel foundries. Ferroalloys are used in steel making for deoxidation as well as for the introduction of alloying elements. They are the most economical way for introducing alloying element into the steel. Ferroalloys impart distinctive qualities to steels and cast irons. The effect on the qualities of steels and cast irons largely depends more or less on the following influences. A change in the chemical composition The removal or the tying up of harmful impurities such as oxygen, nitrogen, sulphur or hydrogen A change in the nature of the solidification, for example, upon inoculation. Ferroalloys are also added in steel production for grain size control as well as for improvement in the mechanical properties of steel. Depending upon the process of steelmaking and the type of steel being made, the requirement of different ferroalloys varies widely. The addition of ferroalloys to steel increases its resistance to corrosion and oxidation, improves its hardenability, tensile strength at high temperature, wear and abrasion resistance with added carbon and increases other desired properties in the steel such as creep strength etc. Ferroalloys are vital inputs for producing all types of steel. They are used as raw material in the production of alloys steel and stainless steel. Ferroalloys are usually classified into two...

Materials Management

Materials Management Materials are the physical items that are needed for producing goods and services. Materials can be raw materials, components, sub-assemblies, parts, tools, consumables, services, or any other type of item. Materials are one of the main inputs to a process, and typically account for a major portion of the  costs. The significance of materials to the efficient operation of organizations is increasing more than ever. Shortages of raw materials, components, and products have been experienced on a global scale. With demand exceeding supply, the price of many materials has increased significantly. Every organization requires raw materials and other materials for its operation that must be acquired, stored, and handled, and there is always necessity for enough stocks of materials and equipment to be maintained for immediate consumption and for short and long term requirements. These stocks or inventory are cash in kind that need utmost care. Therefore the safe custody, up keep and maintenance, handling and proper supply of the materials are of great importance. Materials management is simply the process by which an organization is supplied with the goods and services which it requires to achieve the objectives of buying, storage and movement of materials. It is concerned with the flow of materials from suppliers to the organizational stores and to the user in the production department. It is related to planning, procuring, storing and providing the appropriate materials of right quality, right quantity at right place in right time so as to coordinate and schedule the production activity in an integrative manner in the organization. It includes activities of purchase of various types of materials, manage and control of their storage, and flow and supply of these materials to various places. The materials planning, purchasing, inventory planning, storage, inventory control,...