All dry fluedust is recycled into the blast furnace as one component in a coldbonded dust briquette. It has a very low heating value, about 93 btucubic foot 3. This top gas of the blast furnace is at the temperature and pressure existing at the bf top and usually contaminated with dust and water particles. Blast refers to the combustion air being forced or supplied above atmospheric pressure in a blast furnace, fuel, ores, and flux are continuously supplied through the top of the furnace, while a hot blast of air sometimes with. The top gas contains carbon mono oxide co and is known as blast furnace gas after its cleaning. Blast furnace gas bfg produced from blast furnace bf steelmaking, cleaned in gas cleaning plant and used as a fuel in captive power plants, boilers etc. Design, manufacturing, installation, sales and aftersales servicing of steelmaking machinery, nonferrous metal producing machinery, and cokemaking machinery as well as related equipment for use in japan and overseas. Products ironmaking and steelmaking blast furnace gas. A dryprocess dust collector for blast furnace is equipment for cleansing blast furnace gas. System optimization of blast furnace gas washing with pareto. Through june 2011, the blast furnace ii operated with coke and the blast furnace i operated with charcoal.
Blast furnace bf process is the leading technology for the production of hot metal hm required for steelmaking as well as for the production of the pig iron. In the early 1970s most of the new and revamped blast furnaces were operated under higher. Blast furnace gas bfg is a byproduct of blast furnaces that is generated when the iron ore is reduced with coke to metallic iron. Blast furnace gas cleaning system design millennium steel. Each process step can be programmed into the processing sequence. The energy in the furnace gas has been lost in the conventional wetprocess dust collector as the. A feasibility study for recycling used automotive oil filters. However, the cooling water normally remains uncontaminated and is reused after cooling. The blast furnace gas bfg generated in the bf is cleaned through a series of steps primary cleaning at dust catchercyclone and secondary cleaning at. Ironmaking blast furnaces produce iron, slag and blast furnace gas.
The rest is mostly carbon monoxide, which has a fairly low heating value. This guideline of safety is applicable to blast furnace dept. The new gas cleaning facilities have resulted in an increased ratio of recovered dry flue dust. On the other hand, developed technologies for ironmaking rather than blast furnace opens a window and provide a good opportunity to utilize auxiliary carbonbearing materials that are difficult to utilize in conventional blast furnace ironmaking.
Blast furnace reline project and it is possible that it will not go ahead. Environmental protection agency innovative strategies and economics group md15 office of air quality planning and standards oaqps air quality standards and strategies division research triangle park, nc 27711 prepared by research triangle institute. Blast furnace gas cleaning system rsw ring slit washer. Therefore, there is a strong requirement to utilize bfg for high efficiency and large capacity gas turbine. It is a page of the detail of blast furnace gas cleaning system ring slit washer rsw of steel plantech. Blast furnace it is a tall cylindrical furnace made of steel. Our solutions extend from minor plant upgrades, through products and automations systems, to complete turnkey installations, all executed by our expert. Modern blast furnace bf and converter bof gas cleaning a report of stateoftheart technology by franz reufer and christian davidi synopsis. Blast furnace gas has a high carbon monoxide co content and a low heating value, typical. Blast furnace gas is produced during the iron oxide reduction in blast furnace iron making in which iron ore, coke and limestone are heated and melted in a blast furnace and is an indigenous process gas of the steelworks industry pugh et al. In operation since 1997, it produces around 5,000 tonnes of pig iron during an average of three taps each day. The entire quantum of wastewater originates from the gas cleaning operations. It is narrow at the top and has an arrangement for the introduction of ore and outlet for gases.
Us4152123a gascleaning apparatus and method for high. Experience has shown that the dust content of the gases leaving a blast furnace can be cut by 4 mgm 3 by using a simple and reliable gascleaning system that includes a dust catcher, wet scrubber, venturi tues, valve group, and water separator. Bf gas, characteristics of bf gas, cv, fuel gases, usage of bg gas. For the blast furnace, the problem is largely one of eliminating slips since most blast furnaces in steel plants are equipped with multi stage cleaning devices as. In the blast furnaces bf liquid iron popularly termed as hot metal is produced by the process of reduction at high temperature from raw materials. Cleaning of blast furnace gas the process of liquid iron production in the blast furnace bf generates gas at the furnace top which is an important byproduct of the bf process. Bfg handling in network pipeline is a complex task it. New trends in the application of carbonbearing materials. Mar 19, 2015 blast furnace gas it is the byproduct of blast furnaces that is generated when the iron ore is reduced with coke to produce molten iron.
System optimization of blast furnace gas washing with. A wettype gascleaning system can remove up to 60% of the zinc and lead in the flue gases of blast furnaces operated on a charge. Blast furnace gas it is the byproduct of blast furnaces that is generated when the iron ore is reduced with coke to produce molten iron. A qualitative risk assessment of blast furnace gas on.
Particularly, blast furnace gas hereinafter abbreviated as bfg is byproduct gas from steel work and its amount is huge. Blast furnace gas cleaning free download as powerpoint presentation. In this case, the converter gas, which is generated by oxygen blowing process, is cleaned. Mar 18, 20 fig 2 typical representative composition of blast furnace gas. Alternatively, cyclones are used in some plants for the first offgas cleaning step craig 2008 suvorov 2009.
Experience has shown that the dust content of the gases leaving a blast furnace can be cut by 4 mgm 3 by using a simple and reliable gas cleaning system that includes a dust catcher, wet scrubber, venturi tues, valve group, and water separator. The spray drying absorption process a semidry flue gas desulphurization and cleaning process facilitates a reaction efficiently transforming gaseous pollutants such as e. In figure 5 and 6 they give examples of installed devices for the complete purification of flue gas furnaces. Dry separation of dust particles in the blast furnace top gas before wet scrubbing is commonly done by a gravity.
Blast furnace gas produced from the process is cleaned in gas cleaning plant and used as a fuel in captive power plants, improper gas cleaning excess temperature monitoring system 4 3 3 36 regular inspection lancing hose tuyere. A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally pig iron, but also others such as lead or copper. Gas cleaning systems in ironmaking blast furnaces researchgate. Blast furnaces may have the following ancillary facilities. The gas cleaning system contains two stages, the coarse cleaning system and the fine cleaning system. Since almost 15 years paul wurth umwelttechnik gmbh in essengermany is dedicated to bf and bof gas cleaning. Most gas cleaning systems of blast furnace plants comprise a preliminary cleaning stage and a fine cleaning stage. So2, so3, hcl, hg, and dioxins into a slaked lime caoh2 absorbent to form a stable and dry powdery product that is easy to store and transport. The blast furnace gas bfg generated in the bf is cleaned through a series of steps primary cleaning at. System for cleaning blastfurnace gas in the blastfurnace.
The dust is carried out of the top of the blast furnace in the gas stream is generally referred to as flue dust. Available and emerging technologies for reducing greenhouse gas emissions from the iron and steel industry prepared by the sector policies and programs division office of air quality planning and standards u. In the process, it produces 300,000 cubic metres of cocontaining blastfurnace gas every hour, which is discharged, purified and temporarily stored in a large gas holder. Blast f ur nace gas c leaning blast furnace top glas cleaning systems comprising of dust catcher or axial cy clone for the collection of coarse dust and annular gap scrubber bischoff. Use of sludge from blastfurnace gascleaning systems in. A qualitative risk assessment of blast furnace gas on network.
The difference to blast furnace gas cleaning is that the bof gas in not continuously produced but with a higher temperature, only during the blowing period. Bfg handling in network pipeline is a complex task it has potential hazards like fire. Of the several operating cases, the one in which the heater duty is the highest, shall be regarded as the normal case. The scrubbing water recycled to the scrubber when the turbine is cut off, is permitted to traverse a cooler of the washingwater recovery unit but. A conventional dustcatcher for blast furnace gas comprises a pressure vessel, with a gas inlet and outlet dome 14, a separation chamber 16 and a lower dust hopper 18, and a diffuser pipe 26 extending axially through the gas inlet and outlet dome 14 into the separation chamber 16. Air classification of blast furnace dust catcher dust for zinc load. The blast furnace gas bfg generated in the bf is cleaned through a series of steps primary cleaning at dust catchercyclone and secondary cleaning at gas cleaning plant before. However if it does go ahead, it will be done in conjunction with the no.
Incorporation of selfpreheating process stoves, enabling the generation of hot blast with a temperature of more than 1200oc. Listed below are the highlights of the blast furnace at vsl steels. Through june 2011, the blast furnace ii operated with coke and the blast. Environmental protection agency research triangle park, north carolina 27711 september 2012. Primary gas is cooled by ambient air and mixed with secondary gases from canopy while finally dedusted in low pressure fabric filters.
The blast furnace gas can be used to generate heat. Industry profile draft report prepared for daniel c. Blast furnace gas cleaning systems millennium steel. The ferromanganese gas cleaning installation at duquesne works c.
The present invention generally relates to a dustcatcher for blast furnace gas. Use of sludge from blastfurnace gascleaning systems in the. Jan 22, 2016 cleaning of blast furnace gas the process of liquid iron production in the blast furnace bf generates gas at the furnace top which is an important byproduct of the bf process. The gas leaving the furnace is first conducted through a simple dustcatcher, where the large particles are removed. Our technology base covers the entire blast furnace process route from hot blast and raw material handling, through the furnace and casthouse, to gas cleaning and hot metal slag processing. Our facility consists of a blast furnace that is of 262 m3 capacity and is used for producing pig iron. These systems are selfcontained, automated units with integrated in situ cleaning technology for nonvolatile material deposits. A feasibility study for recycling used automotive oil. As, the blast furnace gas leaves the top of the furnace, it contains dust particles varying in size from about 6mmabout. The fine cleaning stage generally consists of at least one gas scrubber or electrostatic separator. The gas cleaning systems may comprise different processes and methods depending on the specific plant requirements. Primetals technologies gas cleaning solutions offers a wide range of advanced services and technologies to reduce the environmental impact of steel production plants. So by reducing the constituents in blast furnace gas we can increase the calorific value and can be used to generate heat and rise the temperature in any furnace. It is used as fuel gas for heating blast air in the hot blast stoves as well as supplemental fuel in the steel plant.
Heat recovery from stove waste gas at 2300oc for increasing the hot blast temperature 50by about 80oc. The ferromanganese gas cleaning installation at duquesne works. For integrated steelmaking, the primary sources of ghg emissions are blast furnace stoves 43 percent, miscellaneous combustion sources burning natural gas and process gases 30 percent, other process units. The specific volume of the bf gas cumton of hm generated, its chemical composition, and its cv is dependent on the operating parameters of bf, such as i characteristics of the burden materials, ii amount of fluxes charged in the bf, iii distribution of burden materials in the bf stack, iv grade of hot metal being made.
The gases emerging from a highpressure gas furnace are subject to coarse particle separation and then to washing and scrubbing with water before driving an expansion turbine which has a gas bypass so that the turbine can be cut off. The danieli corus tangential cyclone for blast furnace gas cleaning is the most efficient method for dry separation of dust. The energy in blast furnace gas in the forms of pressure and temperature is recovered by a trt generator after passing through the dust collector. Primetals technologies has developed advanced dry top gas cleaning technology for blast furnaces, corex and finex, with considerable benefits for the environment and customers compared to the conventional wet top gas cleaning system. This gas has a considerable energy value so it is burned as a fuel in the hot blast stoves which are used to preheat the air entering the blast furnace to become hot blast.
The mighty centre of the plant is blast furnace 5a. The blast furnace gas, which is heavily loaded with flue dust, is cleaned in a three stage process. Blast furnace gas cleaning plant nippon steel engineering. Gas cleaning and plasma dryetching systems are commercially available in several sizes and models for semiconductor and electronics manufacturing applications. After this date, both blast furnaces started to operate with charcoal, which increased the potential of foam and fines generation. Gas cleaning systems gea engineering for a better world. The pressure drop necessary for the gas cleaning is generated by a fan which sucks the gas through the scrubber and demister. The ferromanganese gas cleaning installation at duquesne. The dust is carried out of the top of the blast furnace in. Steel corporation for many years the equipment used in steel plants for cleaning ordinary, basic blast furnace gas has been fairly well standardized. Project standards and specifications page 7 of 33 rev.
Unless otherwise specified, the design duty shall be 110% of the furnace duty in the normal case. Bof gas cleaning the wet scrubbing technology on the basis of annular gap elements is not only stateoftheart for blast furnace plants, but also applicable for basic oxygen furnace plants bof converter. The most common technologies utilized are venturitype scrubbers, disintegrators, bag filters, and electrostatic precipitators. A feasibility study for recycling used automotive oil filters in a blast furnace metserv page 5 of 69 january 2002 2. To increase the separation efficiency of such a dust hopper 18, it is. Within the system for cleaning of waste gases on blast furnace and bof steel plant in arcelormittal zenica, the various devices for purification of waste gases were built because wet cleaning systems do not have satisfactory efficiency. Technical aspects of high temperature gas cleaning for steel. In the old gas cleaning system, approximately 60% of the dust was recovered as dry dust compared to 80% in the new gas cleaning system. These gases exit the top of the blast furnace and proceed through gas cleaning equipment where particulate matter is removed from the gas and the gas is cooled. Therefore, bluescope steel seeks dgrs for the following alternatives.
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