ULCORED Process Mar18

ULCORED Process

ULCORED Process ULCORED is a direct reduction (DR) process, which produces DRI (direct reduced iron) in a shaft furnace, either from natural gas (NG) or from reducing gas obtained by gasification of coal. Off-gas from the shaft is recycled into the process after carbon di-oxide (CO2) has been captured, which leaves the DR plant in a concentrated stream and goes to storage. The DRI step produces a solid product which is then melted using an electric arc furnace (EAF). The process was designed mainly in 2006 by a team led by LKAB, Voest-alpine and MEFOS. The objective of the ULCORED process was to reduce the NG consumption needed to produce DRI. It was achieved by replacing traditional reforming technology with partial oxidation (POx) of NG. Combined with CCS device, ULCORED can reduce 70 % CO2 emission compared with the average in the BF route. The concept of the ULCORED process involves separating CO2 out of the process gas. It is characterized by an effort to adopt gas based DR process to a minimized emission of green- house gases (GHG), using CO2 capture and storage (CCS) technology and at the same time to a minimized use of energy. The process is designed in a way which allows for the extraction and storage of CO2. The process is therefore also dependent on CCS with a similar in-process capture. The process is based on the utilization of a shifter to convert the carbon monoxide (CO) gas from the shaft to hydrogen (H2) together with a CO2 removal unit. This opens up a new innovative evolution of the process concept. The main features of the ULCORED DR process include (i) use of oxygen (O2) instead of air resulting into an off gas of nearly 100 % CO2 which...

Natural gas and its Usage in Iron and Steel Industry...

Natural gas and its Usage in Iron and Steel Industry Natural gas (NG) is an environmentally friendly non-renewable gaseous fossil fuel which is extracted from deposits in the earth. It is a clean and green fuel with a high efficiency and plays a major role in helping many industries cut emissions and improve the overall air quality. It is normally supplied as (i) piped natural gas (PNG), (ii) compressed natural gas (CNG), and (iii) liquefied natural gas (LNG). Natural gas is a mixture of hydro-carbons consisting primarily of methane (CH4), generally in a percentage of over 85 % by volume. Other hydro-carbons in NG include varying amounts of various higher alkanes such as ethane, propane, and butane etc. It also contains water vapour (H2O) at varying degrees of saturation, or condensed water. It may also contain some small percentage of nitrogen (N2), carbon dioxide (CO2) and hydrogen sulphide (H2S) and helium (He) etc. NG burns with a clean blue luminous flame when mixed with the requisite amount of air and ignited. It is considered one of the cleanest burning fuels. On burning, it produces primarily heat, CO2, and water vapour. NG is a fuel found in deposits in its gas phase. It is colourless and odourless, non-toxic, and lighter than air. It does not contain olefins (hydrocarbons produced during the process of destructive distillation or reforming). It is a highly flammable and combustible gas. Its CAS number is 8006-14-2 and UN number is 1971. Quantities of natural gas are measured in normal cubic meters (corresponding to 0 deg C and 1 atmosphere pressure) or standard cubic feet (corresponding to 16 deg C and 14.73 pounds per square inch absolute pressure). The higher heat value of one cubic meter of natural gas varies from around 9500...

Energiron Direct Reduction Technology Sep08

Energiron Direct Reduction Technology...

Energiron Direct Reduction Technology Energiron direct reduction technology is a gas based direct reduction technology. Energiron process converts iron ore pellets or lumps into metallic iron. It uses the HYL direct reduction technology developed jointly by Tenova and Danieli and is a competitive and environmentally clean solution for lowering the liquid steel production cost. It uses a simple plant configuration, has flexibility for using different sources of reducing gases and has a very efficient and flexible use of iron ores. A key factor in many of the process advantages is directly related to its pressurized operation. Energiron is the name of the direct reduced iron (DRI) product produced by the Energiron direct reduction technology. The product is so named since it carries substantial energy with it which is realized during the steel making process. Energiron is a highly metallized product with the carbon (C) content which is controllable in the range of 1.5 % to 5.0 %. The higher C content of Energiron generates chemical energy in the electric arc furnace (EAF) melting process. The uniquely stable characteristic of Energiron DRI makes it a product which can be safely and easily transported without briquetting, following standard IMO (International Maritime Organization) guidelines. The process is flexible to produce three different product forms, depending on the specific requirements of each user. The three forms of Energiron DRI are cold DRI, HBI (hot briquetted iron) or hot DRI (‘Hytemp’ iron with discharge temperature greater than 700 deg C). Cold DRI discharge is normally used in an adjacent steel melt shop close to the direct reduction plant. It can also be shipped and exported. HBI is the DRI which is discharged hot, briquetted, and then cooled. It is a merchant product usually meant for overseas export. Hytemp Energiron...

Redsmelt process for ironmaking Apr19

Redsmelt process for ironmaking...

Redsmelt process for ironmaking Redsmelt is a new ironmaking process based a two reduction steps. These are (i) pre-reduction of iron bearing materials in a rotary hearth furnace (RHF), and (ii) smelting of the hot pre-reduced iron (DRI, direct reduced iron). Originally a submerged arc furnace (SAF) has been used for the second step. SAF has now been replaced by a coal and oxygen blown converter (oxy-coal reactor) known as ‘New Smelting Technology’ (NST). The RHF reduces green pellets made out of iron ore, reductant fines and binders to produce hot, metallized DRI which is charged to the NST for its smelting to hot metal. Redsmelt process has been conceived to be consisting of a cost-effective and environmental-friendly technology. The important highlights of the process are as follows. The process does not need any prepared charge materials The process does not need electrical energy, since the DRI smelting is carried out using chemical energy The smelter is having high productivity resulting into limited investment cost The process can use practically all the residues generated during various processes of the steel plant (including sludges and oily mill scales), thus it solves the increasing issue of steel wastes treatment The off-gas coming from the smelting reactor is used as a fuel in the RHF, with optimization of the overall energy utilization. This results into effective reduction in energy consumption A Redsmelt demonstration plant with two step smelting reduction process was built and tested in Piombino works (Italy) for the production of hot metal. The demonstration plant was commissioned in the year 2003. The two production steps in the demonstration plant have been based upon pre-reduction of iron-bearing materials in a RHF and smelting of the hot DRI in an oxy-coal converter. The plant has been designed...

Iron Carbide

Iron Carbide Iron carbide is a high melting point, non-pyrophoric, strongly magnetic synthetic compound obtained in granular or powder form. It is composed of three atoms of Fe and one atom C and its chemical formula is Fe3C. The commercial iron carbide consists of around 90 % total iron and around 6 % to 6.5 % of total carbon. The primary use of the product is as a metallic charge during steelmaking for substitution of hot metal, direct reduced iron, or steel scrap. Iron carbide is an intermetallic compound of iron and carbon. It is, more precisely, intermediate transition metal carbide. Its stoichiometric composition consists of 6.67 % carbon and 93.3 % iron (Fe) by weight. It has an orthorhombic crystal structure (Fig 1). It is a hard, brittle material and normally classified as a ceramic in its pure form. It is a frequently found and important constituent in ferrous metallurgy. While iron carbide is present in most steels and cast irons, it is produced as a raw material by the iron carbide process, which belongs to the family of alternative ironmaking technologies. Fig 1 Crystal of iron carbide Iron carbide is a premium quality feed for steelmaking in electric arc furnaces and basic oxygen furnaces. It is available as dark gray granules or powder. It offers matchless metallurgical advantages and outstanding cost savings. It has a density of 7.64 kg/cu m and is thus slightly denser than the liquid iron, which has a density of 6.98 kg/cu m. The iron carbide is composed of three atoms of Fe and one atom C and is also known as cementite. Cementite is an intermetallic compound which is hard, brittle, and metastable because it tends to decompose in ferrite (or austenite) and graphite according to the reaction Fe3C = 3 Fe + C. In fact, this transformation is not...