Rational use of blast furnace gas(BFG) in steel industry can raise economic profit, save fossil energy resources and alleviate the environment pollution. In this paper, a causality diagram is established to describe t...Rational use of blast furnace gas(BFG) in steel industry can raise economic profit, save fossil energy resources and alleviate the environment pollution. In this paper, a causality diagram is established to describe the causal relationships among the decision objective and the variables of the scheduling process for the industrial system, based on which the total scheduling amount of the BFG system can be computed by using a causal fuzzy C-means(CFCM) clustering algorithm. In this algorithm,not only the distances among the historical samples but also the effects of different solutions on the gas tank level are considered.The scheduling solution can be determined based on the proposed causal probability of the causality diagram calculated by the total amount and the conditions of the adjustable units. The causal probability quantifies the impact of different allocation schemes of the total scheduling amount on the BFG system. An evaluation method is then proposed to evaluate the effectiveness of the scheduling solutions. The experiments by using the practical data coming from a steel plant in China indicate that the proposed approach can effectively improve the scheduling accuracy and reduce the gas diffusion.展开更多
Compared with the traditional wet-type de-dusting technology ,the dry-type de-dusting technology is considered to be environmentally friendly and energy-saving. However, the pipes carrying the de-dusted blast fiLrnace...Compared with the traditional wet-type de-dusting technology ,the dry-type de-dusting technology is considered to be environmentally friendly and energy-saving. However, the pipes carrying the de-dusted blast fiLrnace gas (BFG) tends to be corrosive more quickly and seriously. In order to investigate the reasons for the quick corrosion, the gas pipes and auxiliary bellows installed in Baosteel' s newly built BFG dry-type de-dusting system are studied. The corrosive properties of the condensed water, such as the pH value, are measured and analyzed. Meanwhile, various factors that may influence the corrosion rate of the pipes are studied by experiment. On the basis of the investigation and research, the causes of corrosion and leakage on the pipes are discovered. It is the process of dry de-dusting that is responsible ,to a large extent, for the quick corrosion of the pipes. The equipment of spray tower is introduced and its effects are then discussed. This tower is designed to eliminate most of chloridion and neutralized the acid by spraying the alkaline water to the dedusted gas flow. The practical operation shows that the tower helps to lessen the corrosiveness of the dry de-dusted gas effectively. The last part of this study analyzes the possible impacts of the dry-type de-dusting process of the newly built blast furnace (BF) on the main BFG piping which has been in the state of being corroded for years by estimating its potential corrosion rate, and some suggestions on maintenance are given as well.展开更多
A three-dimensional mathematical model,based on differential balances of mass and momentum,hasbeen developed to describe the two-phase flow of gas and liquid through the dropping zone of the blast fur-nace.Agreement b...A three-dimensional mathematical model,based on differential balances of mass and momentum,hasbeen developed to describe the two-phase flow of gas and liquid through the dropping zone of the blast fur-nace.Agreement between observed and calculated values verifies the validity of this model.On the basis of this model,various parameters for the surrounding of the dry zone of Blast FurnaceNo.I-BF of the Beijing Iron and Steel Company have been computed,from which a diagram for demar-cation of fluidization of coke and flooding of slag has been proposed.展开更多
A high-temperature reduction roasting method was used to achieve metallic iron and zinc recovery from blast furnace gas ash(BFA).The reduction processes for Zn-containing and Fe-containing oxides were analyzed in deta...A high-temperature reduction roasting method was used to achieve metallic iron and zinc recovery from blast furnace gas ash(BFA).The reduction processes for Zn-containing and Fe-containing oxides were analyzed in detail by using ther-modynamic equilibrium calculation and the principle of minimum free energy.The results showed that the main reaction in the system is the reduction of ZnFe_(2)_(4)and iron oxides.Over the full temperature range,iron oxides were more easily reduced than zinc oxides.Regardless of the amount of CO contained in the system,the reduction of ZnO to Zn was difficult to proceed below the boiling point(906℃)of Zn.When the reduction temperature is below 906℃,the reduction process of zinc ferrate was ZnFe_(2)_(4)→ZnO;when the reduction temperature is above 906℃,its reduction process becomed ZnFe_(2)_(4)→ZnO→Zn(g).The metallization and dezincification rates of the BFA gradually increased with increasing reaction temperature.As the C/O ratio increased,the metallization and dezincification rates first increased and then decreased.The effect of reduction time on BFA reduction was similar to that of reaction temperature.展开更多
The real-time energy flow data obtained in industrial production processes are usually of low quality.It is difficult to accurately predict the short-term energy flow profile by using these field data,which diminishes...The real-time energy flow data obtained in industrial production processes are usually of low quality.It is difficult to accurately predict the short-term energy flow profile by using these field data,which diminishes the effect of industrial big data and artificial intelligence in industrial energy system.The real-time data of blast furnace gas(BFG)generation collected in iron and steel sites are also of low quality.In order to tackle this problem,a three-stage data quality improvement strategy was proposed to predict the BFG generation.In the first stage,correlation principle was used to test the sample set.In the second stage,the original sample set was rectified and updated.In the third stage,Kalman filter was employed to eliminate the noise of the updated sample set.The method was verified by autoregressive integrated moving average model,back propagation neural network model and long short-term memory model.The results show that the prediction model based on the proposed three-stage data quality improvement method performs well.Long short-term memory model has the best prediction performance,with a mean absolute error of 17.85 m3/min,a mean absolute percentage error of 0.21%,and an R squared of 95.17%.展开更多
Top gas recycling oxygen blast furnace(TGR-OBF)process is a promising ironmaking process.The biggest challenge of the TGR-OBF in operation is the dramatic decrease of top gas volume(per ton hot metal),which once l...Top gas recycling oxygen blast furnace(TGR-OBF)process is a promising ironmaking process.The biggest challenge of the TGR-OBF in operation is the dramatic decrease of top gas volume(per ton hot metal),which once led to hanging-up and shutdowns in practice of the Toulachermet.In order to avoid this weakness,the strategy of medium oxygen blast furnace was presented.The maneuverable zone of the TGR-OBF was determined by the top gas volume,which should not be far from the data of the traditional blast furnace.The deviation of ±12.5% was used,and then the maneuverable blast oxygen content is from 0.30 to 0.47 according to the calculation.The flame temperature and the top gas volume have no much difference compared to those of the traditional blast furnace.The minimum carbon consumption of 357 kg per ton hot metal in the maneuverable zone occurs at the oxygen content of 0.30(fuel saving of 14%).In the unsteady evolution,the N2 accumulation could approach nearly zero after the recycling reached 6 times.Thus far,some TGR-OBF industrial trials have been carried out in different countries,but the method of medium oxygen enriched TGR-OBF has not been implemented,because the accumulation of N2 was worried about.The presented strategy of medium oxygen enriched TGR-OBF is applicable and the strategy with good operational performance is strongly suggested as a forerunner of the full oxygen blast furnace.展开更多
lronmaking using an oxygen blast furnace is an attractive approach for reducing energy consumption in the iron and steel industry. This paper presents a numerical study of gas-solid flow in an oxygen blast fur- nace b...lronmaking using an oxygen blast furnace is an attractive approach for reducing energy consumption in the iron and steel industry. This paper presents a numerical study of gas-solid flow in an oxygen blast fur- nace by coupling the discrete element method with computational fluid dynamics. The model reliability was verified by previous experimental results. The influences of particle diameter, shaft tuyere size, and specific ratio (X) of shaft-injected gas (51G) flowrate to total gas flowrate on the SIC penetration behavior and pressure field in the furnace were investigated. The results showed that gas penetration capacity in the furnace gradually decreased as the particle diameter decreased from 100 to 40 mm. Decreasing particle diameter and increasing shaft tuyere size both slightly increased the SIG concentration near the furnace wall but decreased it at the furnace center. The value of X has a significant impact on the SIG distribution. According to the pressure fields obtained under different conditions, the key factor affecting SIG penetration depth is the pressure difference between the upper and lower levels of the shaft tuyere. If the pressure difference is small, the SIG can easily penetrate to the furnace center.展开更多
In recent decades, many public buildings, located in seismic-prone residential areas, had to grapple with abnormal loads against which the structures were unguarded. In this piece of research, an ordinary three dimens...In recent decades, many public buildings, located in seismic-prone residential areas, had to grapple with abnormal loads against which the structures were unguarded. In this piece of research, an ordinary three dimensional reinforced concrete building is selected as case study. The building is located in an earthquake-prone region; however, it is designed according to seismic building codes. Yet, it is not shielded against abnormal loads, such as blasts. It is assumed that the building suffers a blast load, due to mechanical/thermal installation failure during or after intense seismic oscillations. These two critical incidents are regarded codependent and compatible. So the researchers developed scenarios and tried to assess different probabilities for each scenario and carried out an analysis to ensure if progressive collapse had set in or not. In the first step, two analysis models were used for each scenario; a non-linear dynamic time history analysis and a blast local dynamic analysis. In the second step, having the structural destructions of the first step in view, a pushdown analysis was carried out to determine the severity of progressive collapse and assess building robustness. Finally, the annual probability of structural collapse under simultaneous earthquake and blast loads was estimated and offered.展开更多
Aqueous ammonia (NH3) solution can be used as an alternative absorption for the control of CO2 emitted from flue gases due to its high absorption capacity, fast absorption rate and low corrosion problem. The emissio...Aqueous ammonia (NH3) solution can be used as an alternative absorption for the control of CO2 emitted from flue gases due to its high absorption capacity, fast absorption rate and low corrosion problem. The emission of CO2 from iron and steel plants requires much attention, as they are higher than those emitted from power plants at a single point source. In the present work, low concentration ammonia liquor, 9 wt.%, was used with various additives to obtain the kinetic properties using the blast furnace gas model. Although a solution with a high ammonia concentration enables high CO2 absorption efficiency, ammonium ions are lost as ammonia vapor, resulting in reduced CO2 absorption due to the lower concentration of the ammonia absorbent. To decrease the vaporization of ammonia, ethylene glycol, glycerol and glycine, which contain more than one hydroxyl radical, were chosen. The experiments were conducted at 313 K similar to the CO2 absorption conditions for the blast furnace gas model.展开更多
基金supported by the National Natural Sciences Foundation of China(61473056,61533005,61522304,61603068,U1560102)
文摘Rational use of blast furnace gas(BFG) in steel industry can raise economic profit, save fossil energy resources and alleviate the environment pollution. In this paper, a causality diagram is established to describe the causal relationships among the decision objective and the variables of the scheduling process for the industrial system, based on which the total scheduling amount of the BFG system can be computed by using a causal fuzzy C-means(CFCM) clustering algorithm. In this algorithm,not only the distances among the historical samples but also the effects of different solutions on the gas tank level are considered.The scheduling solution can be determined based on the proposed causal probability of the causality diagram calculated by the total amount and the conditions of the adjustable units. The causal probability quantifies the impact of different allocation schemes of the total scheduling amount on the BFG system. An evaluation method is then proposed to evaluate the effectiveness of the scheduling solutions. The experiments by using the practical data coming from a steel plant in China indicate that the proposed approach can effectively improve the scheduling accuracy and reduce the gas diffusion.
文摘Compared with the traditional wet-type de-dusting technology ,the dry-type de-dusting technology is considered to be environmentally friendly and energy-saving. However, the pipes carrying the de-dusted blast fiLrnace gas (BFG) tends to be corrosive more quickly and seriously. In order to investigate the reasons for the quick corrosion, the gas pipes and auxiliary bellows installed in Baosteel' s newly built BFG dry-type de-dusting system are studied. The corrosive properties of the condensed water, such as the pH value, are measured and analyzed. Meanwhile, various factors that may influence the corrosion rate of the pipes are studied by experiment. On the basis of the investigation and research, the causes of corrosion and leakage on the pipes are discovered. It is the process of dry de-dusting that is responsible ,to a large extent, for the quick corrosion of the pipes. The equipment of spray tower is introduced and its effects are then discussed. This tower is designed to eliminate most of chloridion and neutralized the acid by spraying the alkaline water to the dedusted gas flow. The practical operation shows that the tower helps to lessen the corrosiveness of the dry de-dusted gas effectively. The last part of this study analyzes the possible impacts of the dry-type de-dusting process of the newly built blast furnace (BF) on the main BFG piping which has been in the state of being corroded for years by estimating its potential corrosion rate, and some suggestions on maintenance are given as well.
文摘A three-dimensional mathematical model,based on differential balances of mass and momentum,hasbeen developed to describe the two-phase flow of gas and liquid through the dropping zone of the blast fur-nace.Agreement between observed and calculated values verifies the validity of this model.On the basis of this model,various parameters for the surrounding of the dry zone of Blast FurnaceNo.I-BF of the Beijing Iron and Steel Company have been computed,from which a diagram for demar-cation of fluidization of coke and flooding of slag has been proposed.
基金This work was supported by the National Natural Science Foundation of China(Grant No.51704021)Key Research and Development Projects of Sichuan Province(021YFG0114)+1 种基金Key Research and Development Projects of Shandong Province(2021CXGC010209)the Joint Funds of the National Natural Science Foundation of China(U1560203).
文摘A high-temperature reduction roasting method was used to achieve metallic iron and zinc recovery from blast furnace gas ash(BFA).The reduction processes for Zn-containing and Fe-containing oxides were analyzed in detail by using ther-modynamic equilibrium calculation and the principle of minimum free energy.The results showed that the main reaction in the system is the reduction of ZnFe_(2)_(4)and iron oxides.Over the full temperature range,iron oxides were more easily reduced than zinc oxides.Regardless of the amount of CO contained in the system,the reduction of ZnO to Zn was difficult to proceed below the boiling point(906℃)of Zn.When the reduction temperature is below 906℃,the reduction process of zinc ferrate was ZnFe_(2)_(4)→ZnO;when the reduction temperature is above 906℃,its reduction process becomed ZnFe_(2)_(4)→ZnO→Zn(g).The metallization and dezincification rates of the BFA gradually increased with increasing reaction temperature.As the C/O ratio increased,the metallization and dezincification rates first increased and then decreased.The effect of reduction time on BFA reduction was similar to that of reaction temperature.
基金supported by the National Natural Science Foundation of China(51734004 and 51704069).
文摘The real-time energy flow data obtained in industrial production processes are usually of low quality.It is difficult to accurately predict the short-term energy flow profile by using these field data,which diminishes the effect of industrial big data and artificial intelligence in industrial energy system.The real-time data of blast furnace gas(BFG)generation collected in iron and steel sites are also of low quality.In order to tackle this problem,a three-stage data quality improvement strategy was proposed to predict the BFG generation.In the first stage,correlation principle was used to test the sample set.In the second stage,the original sample set was rectified and updated.In the third stage,Kalman filter was employed to eliminate the noise of the updated sample set.The method was verified by autoregressive integrated moving average model,back propagation neural network model and long short-term memory model.The results show that the prediction model based on the proposed three-stage data quality improvement method performs well.Long short-term memory model has the best prediction performance,with a mean absolute error of 17.85 m3/min,a mean absolute percentage error of 0.21%,and an R squared of 95.17%.
基金supported by the National Key Technologies R&D Program of China(Grant No.2011BAE04B02)Key Technologies R&D Program of Beijing(Grant No.Z161100000716002)
文摘Top gas recycling oxygen blast furnace(TGR-OBF)process is a promising ironmaking process.The biggest challenge of the TGR-OBF in operation is the dramatic decrease of top gas volume(per ton hot metal),which once led to hanging-up and shutdowns in practice of the Toulachermet.In order to avoid this weakness,the strategy of medium oxygen blast furnace was presented.The maneuverable zone of the TGR-OBF was determined by the top gas volume,which should not be far from the data of the traditional blast furnace.The deviation of ±12.5% was used,and then the maneuverable blast oxygen content is from 0.30 to 0.47 according to the calculation.The flame temperature and the top gas volume have no much difference compared to those of the traditional blast furnace.The minimum carbon consumption of 357 kg per ton hot metal in the maneuverable zone occurs at the oxygen content of 0.30(fuel saving of 14%).In the unsteady evolution,the N2 accumulation could approach nearly zero after the recycling reached 6 times.Thus far,some TGR-OBF industrial trials have been carried out in different countries,but the method of medium oxygen enriched TGR-OBF has not been implemented,because the accumulation of N2 was worried about.The presented strategy of medium oxygen enriched TGR-OBF is applicable and the strategy with good operational performance is strongly suggested as a forerunner of the full oxygen blast furnace.
基金We gratefully acknowledge the support of the National Basic Research Program of China (973 Program) (No. 2012CB720401 ) and the Key Project of National Natural Science Foundation of China (No. 51134008).
文摘lronmaking using an oxygen blast furnace is an attractive approach for reducing energy consumption in the iron and steel industry. This paper presents a numerical study of gas-solid flow in an oxygen blast fur- nace by coupling the discrete element method with computational fluid dynamics. The model reliability was verified by previous experimental results. The influences of particle diameter, shaft tuyere size, and specific ratio (X) of shaft-injected gas (51G) flowrate to total gas flowrate on the SIC penetration behavior and pressure field in the furnace were investigated. The results showed that gas penetration capacity in the furnace gradually decreased as the particle diameter decreased from 100 to 40 mm. Decreasing particle diameter and increasing shaft tuyere size both slightly increased the SIG concentration near the furnace wall but decreased it at the furnace center. The value of X has a significant impact on the SIG distribution. According to the pressure fields obtained under different conditions, the key factor affecting SIG penetration depth is the pressure difference between the upper and lower levels of the shaft tuyere. If the pressure difference is small, the SIG can easily penetrate to the furnace center.
文摘In recent decades, many public buildings, located in seismic-prone residential areas, had to grapple with abnormal loads against which the structures were unguarded. In this piece of research, an ordinary three dimensional reinforced concrete building is selected as case study. The building is located in an earthquake-prone region; however, it is designed according to seismic building codes. Yet, it is not shielded against abnormal loads, such as blasts. It is assumed that the building suffers a blast load, due to mechanical/thermal installation failure during or after intense seismic oscillations. These two critical incidents are regarded codependent and compatible. So the researchers developed scenarios and tried to assess different probabilities for each scenario and carried out an analysis to ensure if progressive collapse had set in or not. In the first step, two analysis models were used for each scenario; a non-linear dynamic time history analysis and a blast local dynamic analysis. In the second step, having the structural destructions of the first step in view, a pushdown analysis was carried out to determine the severity of progressive collapse and assess building robustness. Finally, the annual probability of structural collapse under simultaneous earthquake and blast loads was estimated and offered.
基金supported by a grant from the Energy Efficiency & Resources of the Korea Institute of Energy Technology Evaluation and Planning (KETEP)funded by the Korean Government’s Ministry of Knowledge Economy (No. 20092010200011-12-1-000)the Korean Ministry of the Environment (MOE) as the "Human Resource Development Project for Waste to Energy"
文摘Aqueous ammonia (NH3) solution can be used as an alternative absorption for the control of CO2 emitted from flue gases due to its high absorption capacity, fast absorption rate and low corrosion problem. The emission of CO2 from iron and steel plants requires much attention, as they are higher than those emitted from power plants at a single point source. In the present work, low concentration ammonia liquor, 9 wt.%, was used with various additives to obtain the kinetic properties using the blast furnace gas model. Although a solution with a high ammonia concentration enables high CO2 absorption efficiency, ammonium ions are lost as ammonia vapor, resulting in reduced CO2 absorption due to the lower concentration of the ammonia absorbent. To decrease the vaporization of ammonia, ethylene glycol, glycerol and glycine, which contain more than one hydroxyl radical, were chosen. The experiments were conducted at 313 K similar to the CO2 absorption conditions for the blast furnace gas model.