Direct reduction is an iron making process for the new era, which utilizes natural gas to reduce iron ore to produce direct reduced iron dri. This was a simple method used from the iron age to medieval times where iron ore and charcoal were placed in a small furnace. Aftermarket group dedicated to continual support of your midrex plant. Dec 02, 2009 ii absence of post combustion means that much chemical energy is lost in the exit gases and consequently the coal consumption in corex is much higher than in any other iron making process.
Ironmaking and steelmaking metallurgical and materials. Midrex ng process first plant built in 1969 over 70 units constructed worldwide over a. Thus, process technologies using iron ore, such as the bfbof and dreaf combinations, are necessary. Midrex is a gasbased shaft furnace process that converts iron oxides in the form of pellets or lump ore into direct reduced iron dri. The primary objective of iron making is to release iron from chemical combination with oxygen, and, since the blast furnace is much the most efficient process, it receives the most attention here. Ironmaking capability arguably deter mines the strength of. The successful experience with direct reduction of iron at matanzas that initially included four different processes on a smaller scale the h iron process of us steel and an oilbased process from exxon, as well as the hyl and midrex processes, spurred on development and installation of direct iron reduction plants. Finex process of iron making is in development trialoperation stage at posco, pohang works, korea. Alternative ironmaking technologies costly and scarce coking coal.
Alternative methods known as direct reduction are used in over a score of countries, but less than 5 percent of iron is made this way. Direct reduction processes can be divided roughly into two categories. The reducing gas from 1020% co and 8090% h2 isproduced fromnatural gasusing midrexs co2 reforming process and their proprietary. Midrex direct reduction ironmaking hereinafter referred to as the midrex process reduces iron ore using natural gas. Ironmaking and steelmaking are energy intensive and essentially all the carbon entering a steel complex leaves as co2. Iron fe is a relatively dense metal with a silvery white appearance and distinctive.
Your partner for contracting to commissioning direct reduced iron plants. Those that produce a molten hot metal product and those that produce a solid product. The iron ore was originally imported from liberia and its parameters formed the basis of the. The midrex process the worlds most reliable and productive. The hismelt process has a relatively long history, having been conceived in the early 1980s and progressed through two levels of pilot plant 10,000 and 100,000 ta. It is the attributes of the midrex process that give investors and plant owners confidence in the technology and its operation. Direct reduction process an overview sciencedirect topics. 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. Pilot plant 1969, demonstration plant 1971, steady growth in module size from 0.
The midrex process contributes to the biggest share of the directly reduced iron dri produced, which corresponds to about 60% of the world production 12, 20. Hot direct reduced iron charged directly into a melter without cooling. Technical developments in the middrex process abhilasha gulhane, gaurav kumar. The rhf is the process reactor which consists of a flat, refractory hearth rotating inside a stationary, circular tunnel kiln. Direct reduced iron and its production processes ispatguru. In both cases, the objective of the process is to drive off the oxygen contained in various forms of iron ore sized ore, concentrates, pellets, mill scale, furnace dust, etc. Iron ore lump ore, pellets, or a mixture thereof is charged into the reduction shaft, where it is reduced to direct reduced iron dri by the reduction gas in counterflow. Ghosh, phi learning private limited, new delhi11, india, 2010, isbn 9788120336445, printed jay print pack private limited new delhi110015. The dri process has the ability to use low grade coal that is unacceptable for conventional iron making.
The iron nugget is an excellent raw material for eaf or bof steelmaking. Midrex plants can be designed to switch from one dri form to another with no disruption of product flow cdri to hbi, cdri to hot dri hdri, or hdri to hbi. Characterisation of the physical and metallurgical. Interaction reaction between the degradation of coke and the reduction of iron ore in oxygen blast furnace under hydrogenenriched operation. If you continue browsing the site, you agree to the use of cookies on this website. Potential for co2 emissions reduction in midrex direct. So heat energy required for ironmaking process is supplied by this coke and this is a source for carbon of hot metal.
Hot briquetted iron is direct reduced iron discharged from the shaft furnace at. The production of direct reduced iron dri, a basic raw material for making steel, is concentrated in a few countries in the middle east and latin america. Optimization of midrex direct reduced iron use in orebased. Characterisation of the physical and metallurgical properties. Other processes for the gaseous reduction of iron oxide can be grouped into two broad types. 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. Sponge iron production by direct reduction of iron oxide. Pdf corex process in ironmaking elvis marca catachura. Preceding unsigned comment added by mkhomo talk contribs 10.
As direct reduction plants are not built on the same, enormous scale as blast furnaces, their investment costs are lower, and they have been mainly constructed in developing countries where natural gas. 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. This was a simple method used from the iron age to medieval times where iron. Mathematical models of the different operations in a steel plant, including the shaft furnace, form the basis of the model of the system, which was optimized by. When iron is reduced from iron ore, first it could be a solid state.
Characteristics of reduced iron the midrex process produces direct reduced iron hereinafter referred to as dri. Environmentfriendly corex, finex and midrex ironmaking. Two processes, midrex and hylenergiron, share most of the dr. It is a gasbased shaft furnace process is a solid state reduction process which reduces iron ore pellets or lump ore into dri without their melting using reducing gas generally formed from natural gas. The iron carbide process is the most environmentally responsible process available for making virgin steel. Midrex process produces 60% of total dri production with more than 65 plants around the world. Dec 01, 2008 the midrex direct reduction process is based upon a low pressure, moving bed shaft furnace where the reducing gas moves countercurrent to the lump iron oxide ore or iron oxide pellet solids in the bed. The only effluents from the process are water vapor and. Optimization of midrex direct reduced iron use in ore. Gasification and the midrex direct reduction process by.
It constitutes 5 percent by weight of the earths crust, and it is the. An itmk3 plant can be placed either at the iron mine site or near steelmaking facilities. Metallization, reformed natural gas, residual elements, rotary kiln, direct reduced iron and its production processes. Midrex process for direct reduction of iron ore ispatguru. Ironmaking process an overview sciencedirect topics. 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. Corresponding to each temperature interval, typical. Because this process can use natural gas as a reductant and a fuel. Cost effectiveness analysis of hyl and drex dri te chnologies for the iron and steelking industry pa ge 7 steel making process and co 2222 emissionsemissionsemissions steel is primarily made by one of two processes. The performance of midrex plants typically exceeds nominal capacity ratings. The midrex process provides the most complete product discharge options commercially available with the flexibility to process iron oxide pellets and lump ores of varying quality. Optimization of the iron ore direct reduction process. The midrex process the worlds most reliable and productive direct reduction ironmaking technology.
The midrex process is a shafttype direct reduction process where iron ore pellets, lump iron ore or a combination are reduced in a vertical shaft reduction furnace to metallic iron by means of a reduction gas see figure 1. The midrex technology is highly adaptive to our customers needs, which is reflected in a broad variety of configurations. The ironmaking process in the blast furnace is a heat and mass transfer process, and the furnace can be divided into different zones according to physical and chemical state of the feed and temperature. Ironmaking in the rotary hearth furnace rhf is a direct reduction process which utilizes noncoking coal for the reduction of iron ore. We build dri plants that work day in and day out, year after year to provide value for our clients so that. Green steelmaking with the midrex and fastmet processes. Iron fe is a relatively dense metal with a silvery white appearance and distinctive magnetic properties.
Rob cheeley senior sales engineer, midrex direct reduction corporation introduction the production of direct reduced iron dri, a basic raw material for making steel, is concentrated in a few countries in the middle east and latin america. Included in this article also is a discussion of the mining of iron and of its preparation for smelting. The process reduces iron ore using a reforming gas made from natural gas. Be able to understand basic layout of blast furnace, steelmaking shop and continuous casting process. Midrex the worlds leading directreduced iron production. The conventional way of iron and steel making consumes high fuel and even causes emission of carbon dioxide. Nov 05, 2015 midrex is an innovative ironmaking process, developed for the production of directreduced iron dri from iron ores and primarily natural gas. Midrex is an ironmaking process, developed for the production of direct reduced iron dri. Kobe steel, along with midrex technologies, is the world leader in direct reduction dr technologies. Rdcis 2 emerging scenario in iron making more than 90% of world iron production is through blast furnace technology route driving forces.
Generically, the later product type is called direct reduced iron dri. Iron carbide manufacturing process summary iron carbide is a premium quality feed for steelmaking in electric arc furnaces eafs and basic. Abstract this paper presents an overview of the history of the technical developments in midrex process, as well as the latest developments in this field. Detailed modeling of the direct reduction of iron ore in a shaft. Direct reduction process midrex middle east steel industry. It is basically a countercurrent process where a hot and highly reducing gas 95vol. Dri is the steel industrys most flexible metallic charge material, and the midrex process can produce, discharge and transport dri in the form best suited to the application. Direct reduced iron dri is the product which is produced by the direct reduction of iron ore or other iron bearing materials in the solid state by using noncoking coal or natural gas. Pdf the midrex process and the nigerian steel industry. Need to look beyond coking coal possibility to use iron ore fines directly landconstraint environmental considerations eliminate pollutionintensive sintering and. In acceptance of my talk contributions i believe the only remaining issue is in the process article section that indicates that hisarna is a steelmaking process rather than ironmaking. Midrexs primary business is direct reduction ironmaking. The dri is used mainly as the raw material for electric arc furnaces eafs, as a clean iron source substitute for scrap iron. To develop computational and mathematical abilities to be applied for process design and control.
A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. The potential of using direct reduced iron from the midrex process, based on shaft furnace technology, as a partial substitute of pellets in a blast furnace was studied in the paper. Developments in iron making and opportunities for power generation page 4 of 19 october 20, 1999 broadly speaking, there are two classifications of iron making processes. Dr iron production, with the two main processes being midrex 65%. Iron processing, use of a smelting process to turn the ore into a form from which products can be fashioned. By fulfilling more stringent ecological regulations by law, utilization of lowcost, highly available low. The development of new iron making processes, kobelco. Today, the dsr process route 3 which produces molten iron has not made a pronounced contribution to iron production compared to the previous two routes.
The goal of producing steel in nigeria from iron ore was made possible through the midrex process based direct reduction plant at the delta steel company. Midrex gasbased dr technologies is the process to produce iron units which are advantageous in terms of the co2 emissions. Making process iron ore to sponge iron slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Nov 09, 2014 making process iron ore to sponge iron slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Midrex is an innovative ironmaking process, developed for the production of directreduced iron dri from iron ores and primarily natural gas. Also, it is often not possible to produce clean steels with good processing characteristics from many grades of scrap, and a source of nearly pure iron is required. The first metallurgical step is to reduce iron ore to metallic iron, a process which is mostly carried out in a blast furnace. Iron ore, as mined, is a combination of iron with oxygen and various other unwanted substances, generally known as gangue.