Sinter cylinder pelletizer manufacturer
Blast furnace raw materials (iron ore: natural lump ore, sinter, pellet, flux) are the material basis of blast furnace smelting, and concentrate is the basic guarantee for stable operation, high yield, high quality, low consumption and long life of blast furnace. At present, the burden structure of high basicity sinter + acid pellet + lump ore or high basicity sinter + acid pellet ore is basically used in large and medium blast furnace ironmaking
First, sintering proction processblending ore → (belt) → ore tank → first mixing → second mixing → distributor → sintering combined car (ignition, ventilation, sintering) →
crushing → whole grain → blast furnace
concentrate powder, rich ore powder (less than 8mm), flux powder (less than 3mm limestone powder, dolomite powder, etc.) and fuel powder (coke powder or anthracite powder) are mixed, At the same time, a certain amount of water is added to make the mixture into small balls. Then, the mixture which is basically small balls is laid on the sintering machine through the distributor, and the thickness is 400-800mm. Under the negative pressure proced by the suction of the windbox, the heat is transferred downward, which makes the lower material layer graally warm up and burn. When the trolley moves to the end of the sintering machine, the sintering process ends. The red hot agglomerates slide onto the crusher and are sheared. The hot sinter discharged from the sintering machine needs to be crushed and sieved after passing through the cooler
Pelletizing is another method of briquetting iron concentrate or other iron bearing powder. It is a mixture of concentrate powder, flux (sometimes binder and fuel), rolled into green pellets with a diameter of 8 ~ 15mm (larger for steelmaking) in a pelletizing machine, then dried, roasted and consolidated into fine iron bearing raw materials with good metallurgical properties to meet the needs of steel and iron smelting
The differences between "rent" and "rent" as past tense are: different meaning, different usage and different prototype
Rent means rent, crack, tear Rent means to rent Rend usage: the basic meaning is "tear" or "pull", which means to make something split (leaving a rough edge) or leave its attachment under the action of external force. It can be extended to "torture", "run", "walk away" and so on. It can also be used as intransitive verb. When it is used as a transitive verb, it can be followed by a noun or pronoun as the object, or sometimes an adjective or adverb as the compound object of a complement
2. Rented usage: when used as a noun, it means "rent", which is converted into a verb to refer to "rent", that is, the surplus house, land or other idle materials are lent to others in a paid way, and then recovered when needed. It can refer to renting in or renting out. It usually refers to renting land or house. In American English, it can also refer to renting a car, but it is not used to borrow money
3. Different prototypes1. Rent prototype: the prototype verb of rent is rend
2. Rendered prototype: the prototype verb of rendered is rent
here" instead of "house"
In pelletizing proction, the ore powder is first made into green pellets with uniform particle size and sufficient strength. Pelletizing is usually carried out on a disc or cylinder pelletizer. With the help of the capillary action of water, the ore powder forms a spherical core; Then the ball core rolls in the material continuously, adheres to the material, and the ball becomes larger and denser. The bonding between the mineral powder is maintained by molecular water film. The green ball with enough strength can be obtained by using the mineral powder with good hydrophilicity, fine particle size (the mineral powder less than 0.044 mm should account for more than 90% of the total), large specific surface area and good contact conditions, adding appropriate water and a certain amount of binder (bentonite, hydrated lime and quicklime, etc.)< The green pellets were dried (300-600 ℃) and preheated (600-1000 ℃) and then roasted in an oxidizing atmosphere. During the preheating and roasting stage, the oxidation of iron oxide, the decomposition of limestone and the removal of sulfur occur. Roasting is the main stage of pellet consolidation. Solid phase reaction and solid phase sintering play an important role in the consolidation process of pellets, while liquid phase sintering develops only under certain conditions. The roasting temperature is generally 1200 ~ 1300 ℃, mainly using gas or liquid fuel, sometimes also using solid fuel
effect of proportioning composition on pellet quality:
alumina: with AI2O3, the liquid phase content in pellet decreases, porosity increases, Fe2O3 content increases, iron oxide in pellet microstructure tends to be closely combined with silicate minerals, and graally more and larger irregular pores are formed. As the viscosity of silicate binder decreases with the increase of AI2O3, the agglomeration degree and the growth mode of grains are significantly changed ring the roasting process, resulting in the densification of the binder. At the same time, too much AI2O3 forms macroporous and thin-walled structure in the local part of the pellet, which is not concive to the development and growth of grains, and regenerated hematite precipitates around the macropores. Because of the similar lattice of Fe2O3 and AI2O3, the main impurity in the regenerated hematite is AI2O3. AI2O3 can rece the melting point of silicate liquid phase, promote the formation of Fe2O3 and rece the content of FeO. In addition, AI2O3 and FeO will also form solid solution and promote the formation of regenerated free Fe2O3 crystal, so the strength of pellets is reced
MgO: with the increase of MgO, the amount of liquid phase decreases, the viscosity of liquid phase increases, the porosity increases, and the volume shrinkage becomes worse. In addition, there are large pores, irregular pore shape and stress concentration, so the compressive strength decreases. Through chemical analysis, FeO decreases with the increase of MgO, which is because the crystal structure of FeO · Fe203 is anti spinel structure, that is, half of the trivalent iron ions (Fe3 +) are filled in the tetrahedral voids, and the other half of the trivalent iron ions (Fe2 +) and Fe3 +) are filled in the octahedral voids. In MgO FeO system, MgO and FeO belong to cubic system and face centered cubic lattice because of their NaCl type structure. Because of the similar unit cell parameters, similar particle size and the same electricity price, the metal cations are easy to be replaced. In the process of high temperature roasting, Mg2 + ions displace Fe2 +. At this time, Fe2 + has higher activity. On the other hand, e to the increase of porosity, the resistance of oxygen ions to reach the surface of magnetite is reced, so Fe2 + is more easily oxidized, resulting in the increase of Fe203 and the decrease of FeO. It is found that the content of MgO in magnetite increases while the content of FeO decreases with the addition of MgO, which indicates that the replacement of Fe2 + by MgO accelerates the oxidation reaction and the diffusion of reactant layer, which promotes the oxidation of magnetite
silica: the lower the SiO2 in pellets, the better, but in reality some ores are high silicon and low iron ores, so it is meaningful to study the influence of SiO2. When the content of SiO2 increases from 5% to 6.4%, the compressive strength increases from 3700n / ball to 4500n / ball. With the further increase of SiO2, the compressive strength decreases. The results show that when the SiO2 content is 5%, Fe203 and Fe304 are mostly automorphic and semi automorphic, and the silicate is in the shape of large plate, with few round pores and slender cracks in the middle; When the content of SiO2 is 6.4%, Fe203 mostly exists as semi automorphic crystal, with a small amount of fine filamentous microcrystals. The recrystallization is good, the shape and distribution of pores are irregular, with large pores and large cracks. Fe304 increases, and the porosity increases. There are many medium pores in silicate, with thin-walled mesopores and long cracks; When the content of SiO2 is 7.8%, Fe203 and Fe304 are mostly microcrystalline, silicate is flocculent, and staggered with iron oxide. The amount of liquid phase is more than 40%. There are round medium pores, many micro pores, and the distribution of pores is uniform. Fe304 has an increasing trend. The amount of liquid phase is too large. There are extremely serious black round dot like free SiO2 on the surface of Fe304, and there are many pores between silicates; At the stage of SiO2 from 5% to 6.5%, with the increase of SiO2, the amount of liquid phase increases, and the bonding effect is strengthened. When SiO2 is 6.5%, the iron oxide forms the interwoven structure, and the liquid phase fills the pores, mainly forming the closed pores. The structure is dense, and the compactness and compressive strength are the highest; With the increase of SiO2, the pore shape becomes irregular, the free SiO2 increases, the porosity increases, the silicate minerals exist in flocculent form, there are many cracks between the silicates, there are less intergranular between the iron oxides, and the compressive strength decreases. Due to the increase of porosity, oxygen is easier to diffuse, Fe304 is easier to be oxidized and Fe0 content is lower
Cao: the change of Cao is expressed by the change of alkalinity. With the increase of alkalinity from 0.2 to 1.0, the compressive strength increases from 3000n / ball to 4700n / ball, and then decreases with the increase of alkalinity. This is because with the addition of Cao, the silicate slag phase decreases, the calcium ferrite appears, the viscosity of liquid phase decreases, the fluidity becomes better, the porosity decreases, the structure is compact, and the strength increases. When the basicity is 1.0, the structure is the densest and the strength is the highest. If the alkalinity is further increased, there will be more pores e to the excessive amount of liquid phase, and the pores are connected with each other to form a large pore thin-wall structure, resulting in the decrease of strength. For FeO, because Cao reces the melting point of silicate minerals, increases the amount of silicate minerals and decreases the viscosity of liquid phase, the ability to bond iron oxides is enhanced. In the process of high temperature, Ca2 + diffuses into the lattice, while Fe2 + diffuses into the liquid phase in the opposite direction. FeO and SiO2 are easy to combine to form silicate minerals such as forsterite, The presence of calcium bearing magnetite is not concive to the oxidation of Fe304 and the increase of FeO. With the further increase of basicity, the large pore and thin-wall structure is formed in the pellets, which shows that the porosity of pellets increases, the diffusion resistance of oxygen ions decreases, the oxidation of Fe304 is promoted, and FeO decreases
conclusion: with the increase of AI2O3, the compressive strength of pellets decreases, the porosity increases and FeO decreases; With the increase of MgO, the compressive strength of pellets decreases, the porosity increases and FeO decreases; When the SiO2 content is 6.4%, the compressive strength of pellets is the highest. With the further increase of SiO2, the compressive strength of pellets decreases. In the whole process, the porosity increases and FeO decreases; With the further increase of Cao, the compressive strength of pellets decreases, the porosity increases and FeO decreases. Therefore, the results show that when SiO2 is 6.5%, the compressive strength of pellets is high; The high content of AI2O3 and MgO is disadvantageous to the strength of pellets, so their content should be reced as far as possible; In the range of low alkalinity, increasing alkalinity is beneficial to improve the compressive strength of pellets, but FeO content will increase
in the case of laminar flow:
in the case of turbulent flow:
where: G -- acceleration of gravity
ε-- Porosity of material layer
η--- Gas viscosity coefficient
s -- specific surface area of particles
s ρ-- Gas density
from the formula, the main factors affecting the permeability of the material layer are the specific surface area of the material particles and the porosity of the material layer. That is to say, we need to improve ε， Rece s. The air permeability of sinter includes two aspects. One is the air permeability before ignition, the other is the air permeability after ignition. The air permeability of sinter determines the efficiency of sintering proction. The former influences the latter. It is found from the actual proction that the resistance loss of each sintering belt is very different. At the beginning of sintering, because the lower part is too wet, the pellets will be destroyed, and they will bond with each other or block the pores, so the resistance of the material layer is large. Although the thickness of the pre heating zone and the drying zone is small, the resistance loss is not small, because the wet bulb will break ring drying and preheating, and the porosity of the material layer will become smaller. The gas permeability of the combustion zone is the lowest because of the high temperature and the existence of liquid phase in this zone, which has great resistance to the gas. The resistance of sinter zone is the least because of many pores. However, in the case of intense melting, the sinter has dense structure, few pores and poor permeability. Therefore, in sintering proction, the air permeability of mixture must be improved
2.1 to improve the particle size and particle size composition of raw materials
the coarse-grained raw materials are mainly used, because the coarse-grained materials have large porosity and relatively good air permeability. Adding part of rich ore powder or appropriately increasing the amount of return ore can improve the air permeability and increase the sintering output. In the process of sintering, it is beneficial to increase the particle size of raw materials and properly mix the coarse and fine raw materials under possible conditions. However, the possibility of improving the particle size of raw materials is limited. In actual proction, there are not many 8-0 mm ore fines, and not all factories have them
2.2 adding additives to improve the balling performance of the mixture
adding hydrated lime, quicklime, bentonite, water glass, sulfite solution, sodium chloride, calcium chloride and humic acid to the sintering mixture has good effect on improving the gas permeability of the sintering mixture. These particle additives are often a kind of surfactant, which can improve the hydrophilicity of the mixture, and also have gelling performance in many cases. Therefore, the balling performance of the mixture can be greatly improved by the effect of additives
in sintering proction, quicklime and hydrated lime are widely used, especially the hydrated lime colloidal particles with extremely fine particle size after being hydrated and digested. The Ca (OH) 2 colloidal particles distributed in the mixture have obvious colloidal properties, and a certain thickness of hydration film can be formed on its surface. The colloidal particles have the characteristics of double-layer structure, Because the water holding capacity of these hydrophilic Ca (OH) 2 particles widely dispersed in the mixture is much greater than that of iron ore and other materials, it will capture the water content of ore particles and surface, make these particles close to the hydrated lime particles, proce the necessary capillary force, and connect the ore and other materials to form small balls
under laboratory conditions, we studied the influence of white ash ratio on the granulation effect of mixture. Under the same raw material conditions, the air permeability indexes of the mixture with 3% and 5% lime were measured respectively. The results are as follows:
this shows that the air permeability of the mixture has been greatly improved with the increase of lime ratio. In order to solve the problem of lime digestion, we carried out experiments on the digestion process of quicklime. The results show that:
1
2. The digestion time of quicklime is 10-15 minutes
but in actual proction, the lime can not be digested completely in less than 8 minutes from the batching room to the secondary mixing, and there are white spots in the mixture on the sintering machine, which is not good for pelletizing. On the contrary, the expansion effect of lime digestion has a destructive effect on the pelletizing. Therefore, the problem of timely digestion of lime must be solved in the sintering process, otherwise it will backfire< The results show that: (1) under certain raw material and equipment conditions, the discharge port of the existing secondary mixer should be contracted to increase its filling rate, It is one of the effective measures to improve the pelletizing effect by increasing the amount of mixture in the mixer and the residence time of materials
2. Properly adjusting the rotational speed of the drum mixer can improve the fr number and make the mixture run in the best region, which can also significantly improve the pelletizing effect
3. The average diameter of quasi particles can be increased by appropriately recing the inclination angle of the secondary mixer and further extending the granulation time
4. Water addition is the most basic factor to ensure the granulation effect, including the best water addition, stable water addition and the use of atomized water. According to the requirements of mixing and granulation, the water supply and the use of atomized water should be optimized along the length direction
5. The lining structure of the drum mixer has a great influence on the movement law and granulation effect of the mixture. The material with high hydrophobicity and friction coefficient can advance the transition zone from sliding to rolling, which is helpful to improve the granulating effect. It is also found that the sliding zone of the mixture is large and the granulation effect is poor without lining. In addition, the size of the rib plate in the cylinder is also the key structure of the mixer. Without rib plate, granulation effect is poor; The rib plate is too high, the dropping is serious, and the granulating effect is not good. Therefore, the transformation of the inner lining structure of the cylinder mixer is also an important means to strengthen granulation
the above measures have been proved by proction practice and achieved obvious results. Different sintering plants should choose according to their own situation< For many years, engineers and technicians all over the world have been deeply studying the advantages of improving the granulation effect of mixture, and achieved gratifying results: the pelletizing technology characterized by pelletizing plate and fuel separate addition, the pelletizing technology to rece the angle of cylinder mixer, the pelletizing technology to improve the pelletizing effect of mixture, and the pelletizing technology to improve the pelletizing effect of mixture have been developed The new technology of small pellet sintering is characterized by adding feeding scraper or baffle ring and separate addition of fusion and combustion. In recent two years, because of the advantages of the latter, such as not changing the original process configuration and small investment, it has been widely used in domestic sintering plants, and has achieved certain results. China's sintering technology has achieved a new leap. However, the research on the mechanism of mixed pelletizing is only limited to the traditional methods such as lowering the inclination angle, increasing the diameter, increasing the length, changing the rotating speed and adding the distributor in the machine. There is a lack of research and Application on changing the stress state of the mixture to improve the pelletizing rate of the cylinder mixer, which makes the mixed pelletizing effect still in a low efficiency state and limits the proction efficiency Affect proct quality and consumption
pelletizing time, filling rate, mixture properties and suitable mixture moisture are the key points of traditional cylinder mixing technology. The mixed pelletizing technology of cone countercurrent grading cylinder adopts reverse thinking, which is researched and developed by Beijing Airui machinery factory and has obtained the national patent. The purpose is to provide a cone counter current grading cylinder mixing pelletizer. The main points of the technology are: through the change of the internal structure of the mixer to realize the change of the force state of the mixture, to achieve the purpose of compressing the "pitch" of the mixture movement process, extending the effective balling time, increasing the effective rolling distance of the material and improving the balling effect; The technology of segmented cone classification in the machine is used to realize the automatic classification of mixed material particle size, so as to achieve the goal of large particle material going outward first and small particle material returning to pelletizing; The new lining technology is adopted to completely solve the problem of material accumulation at the root of the mixer, realize the recycling of dead material in the mixing process, and improve the pelletizing effect and the useful power of the mixer
3. Implementation plan of pelletizing with mixer in our plant
the existing primary mixer in our plant is ∮ 3 × 7m, the secondary mixer is ∮ 3 × Although the transformation of pellet sintering has been carried out, the pelletizing effect is still not ideal, which seriously affects the output and quality of sinter and restricts the development of ironmaking technology. Based on the above principles, combined with the actual situation that our company needs to stop proction for a short time, the transformation content was re formulated and implemented in 24 hours
3.1 improve the mixing and wetting mode
the mixture is wetted with atomized water automatically in advance in the proportioning room. At the same time, the double shaft quick lime digester with automatic cleaning function is used to completely digest the added quick lime and wet the sintering material in advance
3.2 optimize the mixer process parameters
mainly include the design adjustment of mixer inclination, filling rate, rotating speed and pelletizing time. According to the requirements of water adding intensity in different areas of the mixer, the water adding mode of the primary mixer is changed to three-stage water adding mode; The secondary mixer adds water to the first stage
3.3 the cone counter current grading pelletizing technology is an important part of the mixer after the properties of raw materials, mixer speed, diameter, inclination angle and mixer length are determined. In this technology, the cone counter current spiral is set in the mixer to classify the size of particles, and the stroke of mixture in the mixer is extended to meet the needs of pelletizing effect. In this reconstruction, we have completed the replacement of the special composite lining plate with the characteristics of conic countercurrent. The construction is simple and the reconstruction period is only 36 hours
3.4 effect after the transformation
after the transformation, the conical counter current guide plate was used to make the material move in reverse direction. Because the height of the guide groove showed a grading change, only the material with appropriate particle size graally passed the guide groove and rolled out of the pelletizer, thus improving the pelletizing quality of the mixer. The comparison results before and after the transformation are shown in Table 1 and 2 below< The results before and after transformation are shown in Table 1
sintering negative pressure of mixture particle size composition%
kPa machine speed
m / min output per machine hour
t / machine h material layer thickness
mm
0-33-5 > 51 # 2 # 1 # 2 # 1 # 2 # 1 # 2 #
before transformation 40 28 32 9.0 130.96 1.2 112 400 450
after transformation 13.7 43.2 43.18.7 12.5 1.2 1.44 125 460 520
contrast difference 26.3 15 11.1 0.3 0.5 0.24
calcination, for example, in the early stage of soda instry, the calciner was cylindrical, the furnace fire (carbon fire) was outside the cylinder, and the material sodium bicarbonate was in the cylinder. At present, the steam calciner is a cylinder with a diameter of 3-4 meters and a length of about 30 meters. The material in the cylinder also flows through the steam (in the pipe). The calcining medium is steam with a temperature of more than 300 degrees, and there is no open carbon fire. After calcination, sodium hydrogen becomes soda ash<
roasting 1
circulating fluidized bed roasting technology of inorganic salt ore
I. achievements introction
roasting of natural minerals is the key to the proction of inorganic salt chemical procts. At present, the reverberatory furnace roasting equipment is generally used in the proction, and the materials are turned manually. The equipment is simple and crude, the process is backward, the proct yield is low, the energy consumption is large, and the operating environment is bad, which seriously hinders the development of inorganic salt proction
the backward reverberatory furnace roasting equipment is replaced by a new type of roasting equipment, which uses a circulating fluidized bed (chemical materials and coal are blown up on the bed from below, so that the materials are in the boiling state of fluidization carried by gas, and the temperature control is generally not more than 900 ℃), Fluidized bed fly ash is collected by high temperature cyclone and returned to the furnace for roasting through "J" valve. The roasting efficiency is effectively improved and the coal consumption is greatly reced. For rection roasting of strontium sulfate ore (celestite), the rection rate is increased by more than 10% and the coal is saved by more than 30%. Moreover, the roasted materials are not agglomerated and loose, which is concive to leaching processing. Using circulating fluidized bed roasting, the proction intensity is large, easy to control, the operation site environment is good, and large-scale mechanized continuous proction can be realized< It is well known that two different metals can form eutectic alloys in a certain proportion at a temperature far lower than their respective melting point, and this lower temperature is their low eutectic point. Eutectic sintering is to put eutectic alloy sheet (solder) between chip and carrier (shell or substrate), heat it to eutectic point in a certain protective atmosphere to make it melt, and fill it between die and carrier. At the same time, a small amount of gold on the back of die and carrier surface will enter the molten solder. After cooling, the bonding between alloy solder and gold layer will be formed, So as to complete the chip and shell or other circuit carrier welding thick material layer, low fuel ratio sintering technology and small ball sintering technology
example 2: raw material sintering
I. project content
sinter is the main raw material for blast furnace ironmaking in China. Energy consumption in sintering process and sinter quality are important factors affecting total energy consumption in ironmaking. In this project, a series of measures including thick bed, low fuel ratio sintering and small ball sintering are adopted to improve the energy utilization and sinter quality in sintering process, so as to greatly rece the energy consumption in sintering process and lay a good foundation for coke saving and consumption rection in blast furnace ironmaking< 2. Key technologies and characteristics 1. Transform the existing drum mixer (primary mixing and secondary mixing) into a strong mixing pelletizer
the main measures include: adjusting the angle and speed of the mixer, changing the internal structure, and adopting atomized water pelletizing technology. Requirements: the proportion of 3 mm or more pellets in the mixture should be greater than 75%
2. The fuel dispensing technology and flux dispensing technology
change the original primary fuel dispensing to secondary dispensing, in which most of the fuel is added between the first mixing and the second mixing, so that the fuel is concentrated on the surface of the pellets, and improve the combustion and heat utilization
in order to enrich the surface of flux and improve the consolidation mechanism of sinter, the original primary flux addition was changed to the secondary flux addition according to a certain proportion
3. Segregation distribution technology
a new type of multi roller distributor is adopted to realize the segregation distribution of mixture particle size and fuel, so as to improve the sintering process
4. Increase the mixture temperature
special steam preheating technology is adopted to increase the mixture temperature by more than 20 ℃
5. With the adoption of the above technology, the sintering can achieve thick bed, low temperature and high oxidation sintering, and the sintering fuel consumption is greatly reced. The consolidation mode of sinter is mainly acicular and columnar calcium ferrite, with a small amount of pellets. The obtained sinter has good recibility, high strength and less powder.
the pelletizing process refers to that the fine grinding materials are moistened with water, rolled on the special pelletizing equipment to form green balls, and then preheated and roasted at high temperature to form finished balls. The proct is pellet
pellet sintering, i.e. small pellet sintering, is a process that takes advantage of both sinter and pellet and draws on each other's strong points to make up for its weak points. It is called "mixed pellet sintering" process in Japan. Its method is to first use the disc pelletizer to pelletize and then roll the fuel inside and outside the cylinder mixer. This process improves the permeability of the material layer ring sintering and thus increases the output
sinter pelletizing refers to a kind of working procere and a kind of address. For example, in school, when people say you are a professional, I say I study sinter pelletizing; In other words, sintering pelletizing plays a role in preparing the burden before smelting in iron and steel metallurgy. As for why to prepare, it also involves the characteristics of China's resources. I won't go into details here.
pelletizing machine (or pelletizing machine) is mainly used for pelletizing and briquetting of non-ferrous and ferrous metal ore powder, which can be directly smelted in furnace to improve added value. All metallurgical instry waste, auxiliary materials need to furnace, need to press ball machine to complete. For example: st, pond mud, oxide scale, steel slag, iron concentrate powder, aluminum ash powder, silicomanganese powder, etc. It is mainly used for pelletizing of non-ferrous and ferrous metal ore powder, direct smelting and increasing added value. All metallurgical instry waste, auxiliary materials need to furnace, need to press ball machine to complete. For example: st, pond mud, oxide scale, steel slag, iron concentrate powder, aluminum ash powder, silicomanganese powder, etc
the powerful briquetting machine is mainly used for cold briquetting of pulverized coal, slime, medium coal, coke powder, coking coal and metallurgical powder and refractory materials. All powdery materials that need to be put into the furnace need to be finished by ball press.
The complete process flow of steel plant:
mining → beneficiation → sintering → ironmaking → steelmaking → hot rolling → cold rolling → silicon steel
auxiliary proction process: coking, oxygen proction, gas, self provided electricity and power
iron powder is proced by mineral processing plant after mining, and the iron content is generally more than 60% (the higher the better). To get iron from iron powder, the blast furnace rection method is adopted
in order to adapt to the smelting of blast furnace, iron powder must be processed into blocks first, which requires iron powder and limestone to be made into blocks with uniform size by sintering machine or pelletizing equipment
when it is added to the blast furnace, coke (as fuel and supporting function) is added at the same time, and hot air (about 1150 ℃) is blown into the blast furnace. In this way, liquid iron will be formed at the bottom of the blast furnace and discharged regularly from the taphole of the blast furnace
in the joint venture, in order to use energy, liquid hot metal is directly sent to the steelmaking plant through the hot metal tank
because the ironmaking process is a recing atmosphere, the harmful component sulfur can not be removed. In order to ensure the quality of steel, some processes are now equipped with desulfurization process in front of the furnace of the ironmaking plant or before the furnace of the steelmaking plant
At present, there are two kinds of steelmaking equipment, namely converter and electric furnace
extended data:
steel is a general term for iron carbon alloy with carbon content between 0.02% and 2.06%. The chemical composition of steel can vary greatly. Steel containing only carbon element is called carbon steel (carbon steel) or ordinary steel
in actual proction, steel often contains different alloy elements according to different uses, such as manganese, nickel, vanadium and so on
However, until the invention of nite process in the 19th century, the proction of steel was a high cost and low efficiency workreference: Network steelmaking