Automated classification of gas flow states in blast furnaces using top-camera imagery typically demands a large volume of labeled data,whose manual annotation is both labor-intensive and cost-prohibitive.To mitigate ...Automated classification of gas flow states in blast furnaces using top-camera imagery typically demands a large volume of labeled data,whose manual annotation is both labor-intensive and cost-prohibitive.To mitigate this challenge,we present an enhanced semi-supervised learning approach based on the Mean Teacher framework,incorporating a novel feature loss module to maximize classification performance with limited labeled samples.The model studies show that the proposed model surpasses both the baseline Mean Teacher model and fully supervised method in accuracy.Specifically,for datasets with 20%,30%,and 40%label ratios,using a single training iteration,the model yields accuracies of 78.61%,82.21%,and 85.2%,respectively,while multiple-cycle training iterations achieves 82.09%,81.97%,and 81.59%,respectively.Furthermore,scenario-specific training schemes are introduced to support diverse deployment need.These findings highlight the potential of the proposed technique in minimizing labeling requirements and advancing intelligent blast furnace diagnostics.展开更多
The digital manufacturing theory is applied to the special manufacturing equipments——industrial kilns and furnaces; the concept of digital kilns & furnaces is put forward. The present status of research and appl...The digital manufacturing theory is applied to the special manufacturing equipments——industrial kilns and furnaces; the concept of digital kilns & furnaces is put forward. The present status of research and application for digital technologies in fuel industrial kilns & furnaces is also introduced. Then,take the case of gas fuel kilns & furnaces,their main key technical issues are discussed. Digital kilns & furnaces as an important constituent of the digital equipments are the crucial base of the digital manufacturing. The value of research on digital kilns & furnaces and the application prospect are undoubted. It will improve product quality,reduce the manpower cost,enhance product market competitive ability,promote comprehensively tradition industries such as ceramics,metallurgy industry,and so on.展开更多
The paper refers to the dynamics of solid inclusion in the turbulent flow of liquid metal in induction furnaces. The numerical analysis is carried out adopting LES-based Euler-Lagrange approach in the limit of dilute ...The paper refers to the dynamics of solid inclusion in the turbulent flow of liquid metal in induction furnaces. The numerical analysis is carried out adopting LES-based Euler-Lagrange approach in the limit of dilute conditions.The admixing of carbon particles in induction crucible furnace from the open surface of a melt is simulated.The behaviour of the particles in the bulk of the flow is illustrated as well as compared with the industrial observation of the open surface of the alloy.The paper also contains the description of the novel experimental technique,which is proposed for the verification of the numerical model.The experiment deals with ferromagnetic particles in the flow of Wood's metal in the small induction crucible furnace.This experiment confirms the satisfactory agreement with the numerical results.展开更多
Status and state-of-the-art progress on research,development and application of refractories for aluminum smelting furnaces and holding furnaces were reviewed and discussed in the present paper.The main types of alumi...Status and state-of-the-art progress on research,development and application of refractories for aluminum smelting furnaces and holding furnaces were reviewed and discussed in the present paper.The main types of aluminum smelting furnaces and smelting processes,and the service conditions of refractories and the requirements for refractory lining were also described and discussed.展开更多
Multi-phase nitrides bonded silicon carbide lintel blocks were prepared using industrial SiC(SiC≥98 mass%,3-0.5,≤0.5 and≤0.044 mm),Si powder(Si≥98 mass%,≤0.044 mm),and SiO2 micropowder(SiO2≥96 mass%,d50=0.15 pm)...Multi-phase nitrides bonded silicon carbide lintel blocks were prepared using industrial SiC(SiC≥98 mass%,3-0.5,≤0.5 and≤0.044 mm),Si powder(Si≥98 mass%,≤0.044 mm),and SiO2 micropowder(SiO2≥96 mass%,d50=0.15 pm)as raw materials,and calcium lignosulfonate as the additive,batching,mixing,and molding on a vibration pressure molding machine,drying and then firing at 1420℃for 10 h in high-purity N2.The apparent porosity,the bulk density,the cold modulus of rupture,the hot modulus of rupture,and the linear expansion coefficient of the samples were tested.The phase composition and the microstructure of the samples at different nitriding depths(50,100,and 150 mm)were analyzed by XRD and SEM.The field application effects of the blocks were studied.The results show that:(1)the multi-phase nitrides bonded silicon carbide refractories can dynamically adjust their own phase composition and minimize structural and thermal stresses,improving the service life of key parts of dry quenching furnaces;(2)calcium lignosulfonate can improve the nitriding micro-environment of multi-phase nitrides bonded silicon carbide lintel blocks,successfully increasing the effective nitriding thickness of the blocks to 300 mm;(3)Sinosteel LI RR provides a unique concept in the design of materials and block types as well as the stable and scientific overall structure,promoting the industrialization process of dry quenching furnaces with long service life in China.展开更多
The cooling water flow rate for hearth of large blast furnaces was calculated by simulation. The results show that the cooling water flow rate shall be above 4 200m3/ h for hearth of large blast furnaces; to meet requ...The cooling water flow rate for hearth of large blast furnaces was calculated by simulation. The results show that the cooling water flow rate shall be above 4 200m3/ h for hearth of large blast furnaces; to meet requirements of the increasing smelting intensity and to ensure the safety at the end of the first campaign,the designed maximum cooling water flow rate should be 5 900m3/ h; according to the flow distribution stability and the calculated resistance loss,hearth cooling stave pipes with the specification of 76 mm × 6 mm shall be adopted to assure the flow velocity in pipes of hearth cooling stave in the range of 1. 9- 2. 3 m / s.展开更多
The author describes the fundamental laws of physics, the laws of thermal radiation of ionized and non-ionized gas volumes. Based on open laws, a modern theory of heat transfer and methods for calculating heat transfe...The author describes the fundamental laws of physics, the laws of thermal radiation of ionized and non-ionized gas volumes. Based on open laws, a modern theory of heat transfer and methods for calculating heat transfer in electric arc and flare metallurgical furnaces, furnaces of steam boilers, and combustion chambers of gas turbine plants of power plants have been developed. The use of scientific discovery makes it possible to create innovative electric arc steel-smelting furnaces, flare heating furnaces, and combustion chambers in which the consumption of electricity and fuel is reduced, productivity and service life are increased, and the amount of harmful emissions into the environment is reduced.展开更多
This is a historical compilation and analysis of the world-wide development of kilns and furnaces, covering those ones ranging from ancient earthenware kilns to modern high-tech furnaces、 including nuclear reactors a...This is a historical compilation and analysis of the world-wide development of kilns and furnaces, covering those ones ranging from ancient earthenware kilns to modern high-tech furnaces、 including nuclear reactors and fuel cells. Special emphasis is on energy conservation and environmental protection. the historical lessons from which can be applied to future activities.展开更多
JC 497-92 (96)1 Contents and Applied ScopeThis standard specifies the classification, shapes and dimensions, technical requirements, test methods, inspection rules, marking, packing, transportation, storage and qualit...JC 497-92 (96)1 Contents and Applied ScopeThis standard specifies the classification, shapes and dimensions, technical requirements, test methods, inspection rules, marking, packing, transportation, storage and quality certificate of direct-bonded magnesite-chrome bricks for building materials industry. This standard is applicable to the direct-bonded magnesite-chrome bricks for cement kiln, glass melting tank and other industrial furnaces.2 Normative ReferencesGB 2997: Test method for the apparent porosity, water absorption, bulk density and true porosity of dense shaped refractory productsGB 5070: Chemical analysis method for magnesite-Chrome refractoriesGB 5072: Test method for cold crushing strength of dense shaped refractory productsGB 5989: Test method for refractoriness under load of dense shaped refractory products (Differential, with rising temperature)GB 7320: Test method for thermal expansion of refractory productsGB 7321: Sample preparation for testing of dense shaped refractory productsGB 10324: Type definition of refractory productsGB 10325: Piling, sampling, acceptance, storage and transportation of refractory products展开更多
Hydrogen-based shaft furnace process is gaining more and more attention due to its low carbon emission, and the reduction behavior of iron bearing burdens significantly affects its operation. In this work, the effects...Hydrogen-based shaft furnace process is gaining more and more attention due to its low carbon emission, and the reduction behavior of iron bearing burdens significantly affects its operation. In this work, the effects of reduction degree, temperature, and atmosphere on the swelling behavior of pellet has been studied thoroughly under typical hydrogen metallurgy conditions. The results show that the pellets swelled rapidly in the early reduction stage, then reached a maximum reduction swelling index (RSI) at approximately 40%reduction degree. The crystalline transformation of the iron oxides during the reduction process was the main reason of pellets swelling. The RSI increased significantly with increasing temperature in the range of 850-1050℃, the maximum RSI increased from 6.66%to 25.0%in the gas composition of 100%H_(2). With the temperature increased, the pellets suffered more thermal stress resulting in an increase of the volume. The maximum RSI decreased from 19.78%to 17.35%with the volume proportion of H_(2) in the atmosphere increased from 55%to 100%at the temperature of 950℃.The metallic iron tended to precipitate in a lamellar structure rather than whiskers. Consequently, the inside of the pellets became regular, so the RSI decreased. Overall, controlling a reasonable temperature and increasing the H_(2) proportion is an effective way to decrease the RSI of pellets.展开更多
Blast furnace data processing is prone to problems such as outliers.To overcome these problems and identify an improved method for processing blast furnace data,we conducted an in-depth study of blast furnace data.Bas...Blast furnace data processing is prone to problems such as outliers.To overcome these problems and identify an improved method for processing blast furnace data,we conducted an in-depth study of blast furnace data.Based on data samples from selected iron and steel companies,data types were classified according to different characteristics;then,appropriate methods were selected to process them in order to solve the deficiencies and outliers of the original blast furnace data.Linear interpolation was used to fill in the divided continuation data,the Knearest neighbor(KNN)algorithm was used to fill in correlation data with the internal law,and periodic statistical data were filled by the average.The error rate in the filling was low,and the fitting degree was over 85%.For the screening of outliers,corresponding indicator parameters were added according to the continuity,relevance,and periodicity of different data.Also,a variety of algorithms were used for processing.Through the analysis of screening results,a large amount of efficient information in the data was retained,and ineffective outliers were eliminated.Standardized processing of blast furnace big data as the basis of applied research on blast furnace big data can serve as an important means to improve data quality and retain data value.展开更多
At the beginning of 1990s, Shougang blast furnaces （BFs） No. 2, No. 4, No. 3 and No. 1 were rebuilt se quently for new technological modernization in succession. The campaign life of BFs No. 1, No. 3 and No. 4 reach...At the beginning of 1990s, Shougang blast furnaces （BFs） No. 2, No. 4, No. 3 and No. 1 were rebuilt se quently for new technological modernization in succession. The campaign life of BFs No. 1, No. 3 and No. 4 reaches 16.4, 17.6 and 15.6 years, respectively, and the hot metal output of one campaign reaches 33.8, 35.48 and 26.37 Mt, respectively; the hot metal output of BF effective volume of one campaign reaches 13328, 13991 and 12560 t/m^3, respectively, which reaches the international advanced level of BF high efficiency and long campaign life. In BF desig-ning, several advanced BF long campaign technologies were adopted. BF proper inner profile was optimized, reasona- ble inner profile was adopted, and closed circulating soften water cooling technology was applied in 4 BFs. Double row cooling pipe high efficiency cooling stave was developed which could prolong the service life of bosh, belly and stack. Hot pressed carbon brick and ceramic cup hearth lining structure were applied and optimized. BF operation was improved continuously to ensure stable and smooth operation of BF. Hearth working condition control was strengthened, burden distribution control technology was applied to achieve reasonable distribution of gas flow, and heat load monitoring was strengthened to maintain BF reasonable working inner profile. Proper maintenance at the end of BF campaign was enhanced. Hearth and bottom service life was prolonged by adding titaniferous material and enhancing hearth cooling. Gunning of lining was carried out periodically for the area above tuyere zone.展开更多
The quantificational and normative design is the precondition of improving the design of copper staves for blast furnaces. Based on a 3-dimensional temperature field calculation model, from the view point of heat tran...The quantificational and normative design is the precondition of improving the design of copper staves for blast furnaces. Based on a 3-dimensional temperature field calculation model, from the view point of heat transfer and long campaigns note with the core of forming accretion, the forming-accretion-ability （FAA） and the rib hot surface maximum temperature difference （ATmax） as quantificational indexes to direct and evaluate the design of copper staves for blast furnaces were presented. The application of the two indexes in design essentially embodies the new long campaigns in the stage of design. With the application of the two indexes, good results can be obtained. Firstly, it was suggested that the rib height of a copper stave can be reduced to 15 mm, which is a new method and theory for the reduction of copper staves. Secondly, the influence of insert on FAA and ATmax, is decided by the volume of insert. According to this, the principle of design for the hot surface geometry of copper staves was put forward that the ratio of the rib hot surface to the copper stave hot surface （abbreviated as the ratio of rib to stave） must be maintained in the range of 45% to 55%; for the present copper stave with a 35-40 mm thick rib, the ratio of rib to stave in the range of 50% to 55% can optimize the design of copper staves; for the copper stave with a smaller rib thickness, for example 15 ram, the ratio of rib to stave in the range of 45% to 50% can optimize the design of copper staves. It can be summarized that the thicker the rib thickness, the larger is the ratio of rib to stave. 2008 University of Science and Technology Beijing. All rights reserved.展开更多
This numerical study investigates the effects of using a diluted fuel （50% natural gas and 50% N2） in an industrial furnace under several cases of conventional combustion （air with 21% O2 at 300 and 1273 K） and th...This numerical study investigates the effects of using a diluted fuel （50% natural gas and 50% N2） in an industrial furnace under several cases of conventional combustion （air with 21% O2 at 300 and 1273 K） and the highly preheated and diluted air （1273 K with 10% O2 and 90% N2） combustion （HPDAC） conditions using an in-house computer program. It was found that by applying a combined diluted fuel and oxidant instead of their uncombined and/or undiluted states, the best condition is obtained for the establishment of HPDAC＇s main unique features. These features are low mean and maximum gas temperature and high radiation/total heat transfer to gas and tubes; as well as more uniformity of theirs distributions which results in decrease in NOx pollutant formation and increase in furnace efficiency or energy saving. Moreover, a variety of chemical flame shape, the process fluid and tubes walls temperatures profiles, the required regenerator efficiency and finally the concentration and velocity patterns have been also qualitatively/quantitatively studied.展开更多
The interaction mechanism between the combustion products of pulverized coal injected and coke in the raceway of blast furnace was studied through thermodynamic calculation and experiments.The results indicated that a...The interaction mechanism between the combustion products of pulverized coal injected and coke in the raceway of blast furnace was studied through thermodynamic calculation and experiments.The results indicated that additives significantly affected the melting property of coal ash in high temperature zone.Although the unburnt char,raw coal ash,and catalyzed coal ash failed to wet the coke surface,the wettability of the catalyzed coal ash on the coke was greater than that of the raw coal ash.Since the unburnt char had weak reaction with the coke surface,it showed little influence on the surface morphology of the coke.The interaction between the raw coal ash and the coke gave rise to the increase in the pore size on the coke surface.However,the raw coal ash only affected the coke surface and the entrances of the pores owing to its poor fluidity.After being melted,the catalyzed coal ash was expected to immerge into the inside part of the coke and then react with the coke,resulting in an expansion and increase of coke cavities.The raw coal ash and the unburnt char reduced the coke reactivity,while the catalyzed coal ash improved the coke reactivity.Thereinto,the coal ash containing Fe2O3 exhibited a larger influence on the reactivity than that containing CaO.展开更多
In order to investigate Joule heating power,a three-dimensional finite element model(FEM) was developed to predict Joule heating power in the channels of double-loop inductor. The simulated results were compared with ...In order to investigate Joule heating power,a three-dimensional finite element model(FEM) was developed to predict Joule heating power in the channels of double-loop inductor. The simulated results were compared with experimental data from low load trials for a 400 kW inductor. The results,such as power factor and Joule heating power,show reasonable correlation with experimental data,and Joule heating rate reaches the maximum at the corners and the minimum at the centre of the cross-section area. With increasing relative permeability of iron core,length of coils,current frequency and resistivity of metal melt,the power factor and Joule heating power change. It is concluded that current frequency,the resistivity and length of the coil play a critical role in determining the power factor and Joule heating power,whereas relative permeability of the magnetic core shows no significant influence on them.展开更多
基金financial support provided by the Natural Science Foundation of Hebei Province,China(No.E2024105036)the Tangshan Talent Funding Project,China(Nos.B202302007 and A2021110015)+1 种基金the National Natural Science Foundation of China(No.52264042)the Australian Research Council(No.IH230100010)。
文摘Automated classification of gas flow states in blast furnaces using top-camera imagery typically demands a large volume of labeled data,whose manual annotation is both labor-intensive and cost-prohibitive.To mitigate this challenge,we present an enhanced semi-supervised learning approach based on the Mean Teacher framework,incorporating a novel feature loss module to maximize classification performance with limited labeled samples.The model studies show that the proposed model surpasses both the baseline Mean Teacher model and fully supervised method in accuracy.Specifically,for datasets with 20%,30%,and 40%label ratios,using a single training iteration,the model yields accuracies of 78.61%,82.21%,and 85.2%,respectively,while multiple-cycle training iterations achieves 82.09%,81.97%,and 81.59%,respectively.Furthermore,scenario-specific training schemes are introduced to support diverse deployment need.These findings highlight the potential of the proposed technique in minimizing labeling requirements and advancing intelligent blast furnace diagnostics.
文摘The digital manufacturing theory is applied to the special manufacturing equipments——industrial kilns and furnaces; the concept of digital kilns & furnaces is put forward. The present status of research and application for digital technologies in fuel industrial kilns & furnaces is also introduced. Then,take the case of gas fuel kilns & furnaces,their main key technical issues are discussed. Digital kilns & furnaces as an important constituent of the digital equipments are the crucial base of the digital manufacturing. The value of research on digital kilns & furnaces and the application prospect are undoubted. It will improve product quality,reduce the manpower cost,enhance product market competitive ability,promote comprehensively tradition industries such as ceramics,metallurgy industry,and so on.
基金Item Sponsored by European Social Fund Within the Project "Support for Doctoral Studies at University of Latvia" and the Project Nr.200/0223/1DP/1.1.1.2.0/09/APIA/VIAA/008
文摘The paper refers to the dynamics of solid inclusion in the turbulent flow of liquid metal in induction furnaces. The numerical analysis is carried out adopting LES-based Euler-Lagrange approach in the limit of dilute conditions.The admixing of carbon particles in induction crucible furnace from the open surface of a melt is simulated.The behaviour of the particles in the bulk of the flow is illustrated as well as compared with the industrial observation of the open surface of the alloy.The paper also contains the description of the novel experimental technique,which is proposed for the verification of the numerical model.The experiment deals with ferromagnetic particles in the flow of Wood's metal in the small induction crucible furnace.This experiment confirms the satisfactory agreement with the numerical results.
文摘Status and state-of-the-art progress on research,development and application of refractories for aluminum smelting furnaces and holding furnaces were reviewed and discussed in the present paper.The main types of aluminum smelting furnaces and smelting processes,and the service conditions of refractories and the requirements for refractory lining were also described and discussed.
文摘Multi-phase nitrides bonded silicon carbide lintel blocks were prepared using industrial SiC(SiC≥98 mass%,3-0.5,≤0.5 and≤0.044 mm),Si powder(Si≥98 mass%,≤0.044 mm),and SiO2 micropowder(SiO2≥96 mass%,d50=0.15 pm)as raw materials,and calcium lignosulfonate as the additive,batching,mixing,and molding on a vibration pressure molding machine,drying and then firing at 1420℃for 10 h in high-purity N2.The apparent porosity,the bulk density,the cold modulus of rupture,the hot modulus of rupture,and the linear expansion coefficient of the samples were tested.The phase composition and the microstructure of the samples at different nitriding depths(50,100,and 150 mm)were analyzed by XRD and SEM.The field application effects of the blocks were studied.The results show that:(1)the multi-phase nitrides bonded silicon carbide refractories can dynamically adjust their own phase composition and minimize structural and thermal stresses,improving the service life of key parts of dry quenching furnaces;(2)calcium lignosulfonate can improve the nitriding micro-environment of multi-phase nitrides bonded silicon carbide lintel blocks,successfully increasing the effective nitriding thickness of the blocks to 300 mm;(3)Sinosteel LI RR provides a unique concept in the design of materials and block types as well as the stable and scientific overall structure,promoting the industrialization process of dry quenching furnaces with long service life in China.
文摘The cooling water flow rate for hearth of large blast furnaces was calculated by simulation. The results show that the cooling water flow rate shall be above 4 200m3/ h for hearth of large blast furnaces; to meet requirements of the increasing smelting intensity and to ensure the safety at the end of the first campaign,the designed maximum cooling water flow rate should be 5 900m3/ h; according to the flow distribution stability and the calculated resistance loss,hearth cooling stave pipes with the specification of 76 mm × 6 mm shall be adopted to assure the flow velocity in pipes of hearth cooling stave in the range of 1. 9- 2. 3 m / s.
文摘The author describes the fundamental laws of physics, the laws of thermal radiation of ionized and non-ionized gas volumes. Based on open laws, a modern theory of heat transfer and methods for calculating heat transfer in electric arc and flare metallurgical furnaces, furnaces of steam boilers, and combustion chambers of gas turbine plants of power plants have been developed. The use of scientific discovery makes it possible to create innovative electric arc steel-smelting furnaces, flare heating furnaces, and combustion chambers in which the consumption of electricity and fuel is reduced, productivity and service life are increased, and the amount of harmful emissions into the environment is reduced.
文摘This is a historical compilation and analysis of the world-wide development of kilns and furnaces, covering those ones ranging from ancient earthenware kilns to modern high-tech furnaces、 including nuclear reactors and fuel cells. Special emphasis is on energy conservation and environmental protection. the historical lessons from which can be applied to future activities.
文摘JC 497-92 (96)1 Contents and Applied ScopeThis standard specifies the classification, shapes and dimensions, technical requirements, test methods, inspection rules, marking, packing, transportation, storage and quality certificate of direct-bonded magnesite-chrome bricks for building materials industry. This standard is applicable to the direct-bonded magnesite-chrome bricks for cement kiln, glass melting tank and other industrial furnaces.2 Normative ReferencesGB 2997: Test method for the apparent porosity, water absorption, bulk density and true porosity of dense shaped refractory productsGB 5070: Chemical analysis method for magnesite-Chrome refractoriesGB 5072: Test method for cold crushing strength of dense shaped refractory productsGB 5989: Test method for refractoriness under load of dense shaped refractory products (Differential, with rising temperature)GB 7320: Test method for thermal expansion of refractory productsGB 7321: Sample preparation for testing of dense shaped refractory productsGB 10324: Type definition of refractory productsGB 10325: Piling, sampling, acceptance, storage and transportation of refractory products
基金financially supported by the National Natural Science Foundation of China (No.51904063)the China Postdoctoral Science Foundation (No.2018M640259)+2 种基金the Fundamental Research Funds for the Central Universities(No.N2025023)the Key research and development project of Hebei Province (No.21314001D)the Plan of Xingliao Talents,China (No.XLYC1902118)。
文摘Hydrogen-based shaft furnace process is gaining more and more attention due to its low carbon emission, and the reduction behavior of iron bearing burdens significantly affects its operation. In this work, the effects of reduction degree, temperature, and atmosphere on the swelling behavior of pellet has been studied thoroughly under typical hydrogen metallurgy conditions. The results show that the pellets swelled rapidly in the early reduction stage, then reached a maximum reduction swelling index (RSI) at approximately 40%reduction degree. The crystalline transformation of the iron oxides during the reduction process was the main reason of pellets swelling. The RSI increased significantly with increasing temperature in the range of 850-1050℃, the maximum RSI increased from 6.66%to 25.0%in the gas composition of 100%H_(2). With the temperature increased, the pellets suffered more thermal stress resulting in an increase of the volume. The maximum RSI decreased from 19.78%to 17.35%with the volume proportion of H_(2) in the atmosphere increased from 55%to 100%at the temperature of 950℃.The metallic iron tended to precipitate in a lamellar structure rather than whiskers. Consequently, the inside of the pellets became regular, so the RSI decreased. Overall, controlling a reasonable temperature and increasing the H_(2) proportion is an effective way to decrease the RSI of pellets.
基金This work is financially supported by the National Nature Science Foundation of China(No.52004096)the Hebei Province High-End Iron and Steel Metallurgical Joint Research Fund Project,China(No.E2019209314)+1 种基金the Scientific Research Program Project of Hebei Education Department,China(No.QN2019200)the Tangshan Science and Technology Planning Project,China(No.19150241E).
文摘Blast furnace data processing is prone to problems such as outliers.To overcome these problems and identify an improved method for processing blast furnace data,we conducted an in-depth study of blast furnace data.Based on data samples from selected iron and steel companies,data types were classified according to different characteristics;then,appropriate methods were selected to process them in order to solve the deficiencies and outliers of the original blast furnace data.Linear interpolation was used to fill in the divided continuation data,the Knearest neighbor(KNN)algorithm was used to fill in correlation data with the internal law,and periodic statistical data were filled by the average.The error rate in the filling was low,and the fitting degree was over 85%.For the screening of outliers,corresponding indicator parameters were added according to the continuity,relevance,and periodicity of different data.Also,a variety of algorithms were used for processing.Through the analysis of screening results,a large amount of efficient information in the data was retained,and ineffective outliers were eliminated.Standardized processing of blast furnace big data as the basis of applied research on blast furnace big data can serve as an important means to improve data quality and retain data value.
文摘At the beginning of 1990s, Shougang blast furnaces （BFs） No. 2, No. 4, No. 3 and No. 1 were rebuilt se quently for new technological modernization in succession. The campaign life of BFs No. 1, No. 3 and No. 4 reaches 16.4, 17.6 and 15.6 years, respectively, and the hot metal output of one campaign reaches 33.8, 35.48 and 26.37 Mt, respectively; the hot metal output of BF effective volume of one campaign reaches 13328, 13991 and 12560 t/m^3, respectively, which reaches the international advanced level of BF high efficiency and long campaign life. In BF desig-ning, several advanced BF long campaign technologies were adopted. BF proper inner profile was optimized, reasona- ble inner profile was adopted, and closed circulating soften water cooling technology was applied in 4 BFs. Double row cooling pipe high efficiency cooling stave was developed which could prolong the service life of bosh, belly and stack. Hot pressed carbon brick and ceramic cup hearth lining structure were applied and optimized. BF operation was improved continuously to ensure stable and smooth operation of BF. Hearth working condition control was strengthened, burden distribution control technology was applied to achieve reasonable distribution of gas flow, and heat load monitoring was strengthened to maintain BF reasonable working inner profile. Proper maintenance at the end of BF campaign was enhanced. Hearth and bottom service life was prolonged by adding titaniferous material and enhancing hearth cooling. Gunning of lining was carried out periodically for the area above tuyere zone.
基金the National Natural Science Foundation of China(No.60672145).
文摘The quantificational and normative design is the precondition of improving the design of copper staves for blast furnaces. Based on a 3-dimensional temperature field calculation model, from the view point of heat transfer and long campaigns note with the core of forming accretion, the forming-accretion-ability （FAA） and the rib hot surface maximum temperature difference （ATmax） as quantificational indexes to direct and evaluate the design of copper staves for blast furnaces were presented. The application of the two indexes in design essentially embodies the new long campaigns in the stage of design. With the application of the two indexes, good results can be obtained. Firstly, it was suggested that the rib height of a copper stave can be reduced to 15 mm, which is a new method and theory for the reduction of copper staves. Secondly, the influence of insert on FAA and ATmax, is decided by the volume of insert. According to this, the principle of design for the hot surface geometry of copper staves was put forward that the ratio of the rib hot surface to the copper stave hot surface （abbreviated as the ratio of rib to stave） must be maintained in the range of 45% to 55%; for the present copper stave with a 35-40 mm thick rib, the ratio of rib to stave in the range of 50% to 55% can optimize the design of copper staves; for the copper stave with a smaller rib thickness, for example 15 ram, the ratio of rib to stave in the range of 45% to 50% can optimize the design of copper staves. It can be summarized that the thicker the rib thickness, the larger is the ratio of rib to stave. 2008 University of Science and Technology Beijing. All rights reserved.
基金Supported by the National Iranian Oil Company (NIOC)
文摘This numerical study investigates the effects of using a diluted fuel （50% natural gas and 50% N2） in an industrial furnace under several cases of conventional combustion （air with 21% O2 at 300 and 1273 K） and the highly preheated and diluted air （1273 K with 10% O2 and 90% N2） combustion （HPDAC） conditions using an in-house computer program. It was found that by applying a combined diluted fuel and oxidant instead of their uncombined and/or undiluted states, the best condition is obtained for the establishment of HPDAC＇s main unique features. These features are low mean and maximum gas temperature and high radiation/total heat transfer to gas and tubes; as well as more uniformity of theirs distributions which results in decrease in NOx pollutant formation and increase in furnace efficiency or energy saving. Moreover, a variety of chemical flame shape, the process fluid and tubes walls temperatures profiles, the required regenerator efficiency and finally the concentration and velocity patterns have been also qualitatively/quantitatively studied.
基金financially supported by the National Natural Science Foundation of China (No.51374166, 51574189)the Natural Science Foundation Research Project of Shaanxi,China(No.2016JQ5041)the Shaanxi Province Department of Education Fund, China(No.16JK1450)
文摘The interaction mechanism between the combustion products of pulverized coal injected and coke in the raceway of blast furnace was studied through thermodynamic calculation and experiments.The results indicated that additives significantly affected the melting property of coal ash in high temperature zone.Although the unburnt char,raw coal ash,and catalyzed coal ash failed to wet the coke surface,the wettability of the catalyzed coal ash on the coke was greater than that of the raw coal ash.Since the unburnt char had weak reaction with the coke surface,it showed little influence on the surface morphology of the coke.The interaction between the raw coal ash and the coke gave rise to the increase in the pore size on the coke surface.However,the raw coal ash only affected the coke surface and the entrances of the pores owing to its poor fluidity.After being melted,the catalyzed coal ash was expected to immerge into the inside part of the coke and then react with the coke,resulting in an expansion and increase of coke cavities.The raw coal ash and the unburnt char reduced the coke reactivity,while the catalyzed coal ash improved the coke reactivity.Thereinto,the coal ash containing Fe2O3 exhibited a larger influence on the reactivity than that containing CaO.
基金Project(50876116) supported by the National Natural Science Foundation of ChinaProject(2007CK3077) supported by Innovative Program of Hunan Science and Technology AgencyProject(1343-77225) supported by the Graduate School of Central South University
文摘In order to investigate Joule heating power,a three-dimensional finite element model(FEM) was developed to predict Joule heating power in the channels of double-loop inductor. The simulated results were compared with experimental data from low load trials for a 400 kW inductor. The results,such as power factor and Joule heating power,show reasonable correlation with experimental data,and Joule heating rate reaches the maximum at the corners and the minimum at the centre of the cross-section area. With increasing relative permeability of iron core,length of coils,current frequency and resistivity of metal melt,the power factor and Joule heating power change. It is concluded that current frequency,the resistivity and length of the coil play a critical role in determining the power factor and Joule heating power,whereas relative permeability of the magnetic core shows no significant influence on them.
