Directreduced iron an overview sciencedirect topics. In recent years blast furnace corex iron making units prefers. State of direct reduction and reduction smelting processes j. Ferrous metallurgy is the metallurgy of iron and its alloys. Siemens is currently building the worlds largest corex based plant in china. Discharge screws convey the dri from the reduction shaft into the melter gasifier. The corex process is a twostage smelting reduction process, in which hot metal can be produced from noncoking coal and iron ores. Operating line prediction of corex iron making process using rist diagram c srishilan,1 anand vivek2 and ajay kumar shukla1 1 department of metallurgical and materials engineering, indian. The process differs from the conventional blast furnace route in that low grade coal can be directly used for ore reduction and melting work, eliminating the need for coke making units. So heat energy required for ironmaking process is supplied by this coke and this is a source for carbon of hot metal. The corex process offers high smelting intensity and hence higher productivity, ability to use various types of noncoking coals, use of iron ore fines. Iscors corex plant has a yearly capacity of 300 000 t. Rio tinto has for many years been a trusted supplier to the worlds iron and steel industry, particularly in south east asia, where its australian mines offer costeffective raw material.
This section basically explains the system function in detail. This process, has been developed and is being marketed by voestalpine industrienlagenbau vai, austria. Charge is charged into a reduction shaft where they are reduced to direct reduced iron dri by a reduction gas moving in counter flow. The dri is used mainly as the raw material for electric arc furnaces eafs, as a clean iron source substitute for scrap iron. The blast furnace was the workhorse for making pig iron in the nineteenth and twentieth centuries and will.
An itmk3 plant can be placed either at the iron mine site or near steel making facilities. The main reagents for the corex process are iron ore, noncoking coal, and oxygen. A special manufacturing process is making the production of iron much more environmentally friendly. The proportions of material used vary according to the process and the type of steel required. Hisarna process is a smelting reduction process for producing liquid iron directly from iron ore fines iof and coal. During the late twentieth century, several new initiatives have been taken for the development of the. Optimum process conditions for the production of pig iron by corex process. The finex is the latest addition and an optimized fineore smelting reduction sr iron making process based on the direct use of the coal and iron ore fines. New zealand is also one of the few countries that has increased steel production over the last decade.
To develop computational and mathematical abilities to be applied for process design and control. Steel is made by refining liquid iron and then cooling and shaping it in a mold. It is not known when or where the smelting of iron from ores began, but by the end of the 2nd millennium bc iron was being produced from iron ores from at least greece to india, and more. The iron ore is directly charged into the reduction shaft along with limestone and dolomite additives. The primary reduction of the iron oxide feed stocks takes place in the reduction shaft furnace. Iron making process, full notes, pdf, ebooks, results 1 to 1 of 1. Corex process in iron making slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Raw materials for corex and their influence on furnace. Steel is an alloy of iron and carbon, whose characteristics are determined by the other elements in addition to carbon. If you continue browsing the site, you agree to the use of cookies on this website.
Predominant source of iron in many blast furnace processes. Further iron making development took the other way of alternative to the bf direct and smelting reduction processes. The coke is of course the source of reduction of iron ore by providing carbon to iron ore and when it burns, and it also generates a lot of heat. Iron making process, full notes, pdf, ebooks, popular topic for study. This was a simple method used from the iron age to medieval times where iron ore and charcoal were placed in a small furnace. Optimum process conditions for the production of pig iron. The corex process is the best known first generation process. Pdf corex process in ironmaking elvis marca catachura. Overview of corex plant in operation in the corex process, all metallurgical work is carried out in two separate process reactors. The itmk3 process is similar to fasmelt except that there is no melting process and therefore the product will be in the form of pig iron nugget. Jswsl produces basic pellets with basicity caosio 2 0. Direct reduction process an overview sciencedirect topics. In addition, the corex process can use iron oxides containing up to 80% lump ore. Your partner for contracting to commissioning direct reduced iron plants.
Be able to understand basic layout of blast furnace, steelmaking shop and continuous casting process. The corex process has been developed as an alternative to bf iron making, which uses noncoking coal and a small amount of coke as fuel, and pelletlump ore as iron bearing feed. Zealand are both unusual, making the overall process almost unique. The corex process consists of two main parts a reduction shaft and melter gasifier. Iron making and general industry technologies iron making technologies 47 3a3. The sponge iron is delivered as hot from the reduction shaft furnace by screw. The most interesting feature of the corex process is the separation of iron reduction and smelting operations into two separate reactors, which are reduction shaft and meltergasifier, therefore it is a twostage process. Unlike the blast furnace the corex process does not use a hot blast of nitrogen, thereby greatly reducing nox gas emissions, but instead uses oxygen.
The typical iron oxide mix for corex is 30% lump ore and 70% pellets. Sintering process sinter making is a method of fusing iron ore fines into larger particles suitable for charging into the blast furnace. Steel is produced via two main routes integrated smelting involving blast furnace bf iron making followed by basic oxygen furnace bof, and in electric arc furnaces eaf. Its current share of the domestic steel market is about 90%.
The earliest surviving iron artifacts, from the 4th millennium bc in egypt, were made from meteoritic iron nickel. Characteristics of reduced iron the midrex process produces direct reduced iron hereinafter referred to as dri. Efficient and environmentally friendly smelting reduction. Directly reduced iron directly reduced iron is a product of iron steel direct reduction from ores in the solid. Annual hot metal production by blast furnace process, dri, as well as crude steel from. Ironmaking and steelmaking metallurgical and materials. In the first step the iron ore is reducedin a shaft furnace. Corex process distinguishes itself from the blast furnace route by i direct use of noncoking coal as reducing agent and energy source, ii iron ore can be directly and feasibly charged to the process in form of lump ore, and pellets, and iii use of pure oxygen instead of nitrogen rich hot blast. Making iron conversion to steethe basic raw material for steel manufacture is either the hot metal from the blast furnace, steel scrap or a mixture of both. Ironmaking 101 from ore to iron with blast furnaces. This technology was developed for the treatment of the waste fines in.
In the corex process, a combination of lump ore, pellets, and sinter is prereduced to about 90% metallization sponge iron in the reduction shaft furnace by a gas containing co and h 2 supplied from the melter gasifier, which is the main reactor of the corex plant. The process reduces iron ore using a reforming gas made from natural gas. The corex process is being projected as an alternative for blast furnace iron making. Operational results proved stable operations with a lump ore fraction up to 80%. The corex technology is a cost efficient, environmentally friendly and industrially accomplished alternative to the blast furnace route for the production of hot metal from iron ore and coal. The process differs from the conventional blast furnace route. The outstanding feature of the corex process is that it uses conventional coal instead of coking coal, the customary ingredient.
The finex process, developed by siemens vai and posco is an innovative methodology in which molten iron is produced directly using iron ore fines and noncoking coal. The corex process offers high smelting intensity and hence higher productivity, ability to use various types of noncoking coals, use of iron ore fines to an extent, low net operating cost. The main benefits of the finex process include process efficiency, lower environmental impact, process simplification through removal of process steps. Use of pellet atleast partially is a must for corex process. Thus, for instance, the corex process, which is used for commercial purposes. Iron ore, as mined, is a combination of iron with oxygen and various other unwanted substances, generally known as gangue. The manufacturing process iron ore is converted to steel via two main steps. Finex process is a fluidized bed based process using ore fines instead using iron ore lumps and pellets. It represents a new, potentially more efficient way of making iron and is being developed for substantial reduction of carbon emissions from the ironmaking process. The first metallurgical step is to reduce iron ore to metallic iron, a process which is mostly carried out in a blast furnace, using coke as both a fuel and reducing agent. In addition, the corex process can use iron oxides containing up to 80% lump ore and uses non coking coal directly as a reducing agent.
The highlight of the process is it does not require coking coal. The coal consumption of the corex process is large with a net fuel rate ofkgtone of hot metal thm. Pig iron is divided into steel making pig iron, which is intended for further processing to steel by various refining processes, and foundry pig iron, from which cast iron is produced by remelting. Iron is made by reacting iron ore iron oxide and impurities, coke a reductant and limestone caco 3 in a blast furnace iron ores with lower iron content such as taconite are first processed to concentrate the iron level and drive off volatile impurities. Environmentfriendly corex process of iron and steel making. Corex is a smeltingreduction process developed by vai, for costefficient and environmentally friendly production of hot metal from iron ore and low grade coal. Pdf minimization of exergy losses in the corex process. The quality of the hot metal produced by the plant is similar to that of blastfurnace hot metal. Operating line prediction of corex iron making process using rist diagram c srishilan,1 anand vivek2 and ajay kumar shukla1 1 department of metallurgical and materials engineering, indian institute of technology madras, chennai, 600036 india. In a dr process, iron ore pellets andor lump iron ores are reduced by a reducing gas to produce dri or hot briquetted iron hbi. There are two basic methods for making liquid iron. Direct iron ore smelting reduction process dios technology overview. Operating line prediction of corex ironmaking process. The iron nugget is an excellent raw material for eaf or bof steel making.
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