The large quantity of sediment produced in the hearth during vanadium titano-magnetite smelting in a blast furnace（BF） affects the stability of the blast furnace operation. Testing and analysis of the sediment in th...The large quantity of sediment produced in the hearth during vanadium titano-magnetite smelting in a blast furnace（BF） affects the stability of the blast furnace operation. Testing and analysis of the sediment in the hearth of Chengde Iron and Steel Company？s BF No.7 revealed that it was mainly concentrated in the location below the tuyere and above the iron notch. Notably, some of the bonding material（sediment） consisted of greater than 50% pig iron, and the pig iron distributed in the slag was granular. It is proposed that a large quantity of Ti C and Ti（C,N） are deposited on the surface of the pig iron. These high melting point materials mix with iron drops, preventing the slag from flowing freely, thus leading to the formation of bonding materials. In addition, the viscosity and melting temperature of the slag in the tuyere areas fluctuate greatly, and thus the properties of the slag are unstable. Moreover, the slag contains large quantities of carbon, which results in the reduction of Ti O2. The resultant precipitation of Ti is followed by the formation of Ti C in the slag, which also leads to an increase in the viscosity of the slag and difficulty in achieving separation of the slag-iron. In fact, all of these factors interact with each other, and as a result, sediment is formed when the operating conditions in the hearth fluctuate.展开更多
The permeability index is one of the important production indicators to monitor the operation of blast furnace.It is crucial to grasp the trends of changes in the new permeability index in time.For the complex vibrati...The permeability index is one of the important production indicators to monitor the operation of blast furnace.It is crucial to grasp the trends of changes in the new permeability index in time.For the complex vibration spectrum of the permeability index,a prediction model of the permeability index based on the VMD-PSO-BP(variational mode decomposition-particle swarm optimization-back propagation)method was proposed.Firstly,the key factors that affect the permeability index of blast furnace were studied from multiple perspectives.Then,the permeability index was divided into multiple sub-modes based on the difference of frequency bands by the VMD algorithm,and a PSO-BP prediction model was established for each sub-mode.Finally,the prediction results of each sub-mode were summed to obtain the final one.The results show that the composite prediction accuracy by using the VMD algorithm is 3%higher than that of the traditional prediction method,which has better applicability.展开更多
With the continuous and rapid development of modern ecological environment protection, the key value role of environmental testing has become more and more prominent. How to effectively use diversified environmental t...With the continuous and rapid development of modern ecological environment protection, the key value role of environmental testing has become more and more prominent. How to effectively use diversified environmental testing techniques to comprehensively assist in promoting the high-quality development of environmental protection has attracted much attention in the industry. Based on this, this paper firstly introduces the multi-dimensional value function of environmental testing in environmental protection, analyzes the present situation and existing problems of environmental testing, and combining with the relevant practical experience, respectively, discusses the methods and paths to improve the level of environmental testing and optimize environmental protection from various angles and aspects such as the application of environmental testing information system based on modern science and technology, and expounds some personal opinions on this.展开更多
基金Item Sponsored by National Natural Science Foundation of China(U1360205)
文摘The large quantity of sediment produced in the hearth during vanadium titano-magnetite smelting in a blast furnace（BF） affects the stability of the blast furnace operation. Testing and analysis of the sediment in the hearth of Chengde Iron and Steel Company？s BF No.7 revealed that it was mainly concentrated in the location below the tuyere and above the iron notch. Notably, some of the bonding material（sediment） consisted of greater than 50% pig iron, and the pig iron distributed in the slag was granular. It is proposed that a large quantity of Ti C and Ti（C,N） are deposited on the surface of the pig iron. These high melting point materials mix with iron drops, preventing the slag from flowing freely, thus leading to the formation of bonding materials. In addition, the viscosity and melting temperature of the slag in the tuyere areas fluctuate greatly, and thus the properties of the slag are unstable. Moreover, the slag contains large quantities of carbon, which results in the reduction of Ti O2. The resultant precipitation of Ti is followed by the formation of Ti C in the slag, which also leads to an increase in the viscosity of the slag and difficulty in achieving separation of the slag-iron. In fact, all of these factors interact with each other, and as a result, sediment is formed when the operating conditions in the hearth fluctuate.
基金supports from the National Natural Science Foundation of China Youth Fund Project(52004096).
文摘The permeability index is one of the important production indicators to monitor the operation of blast furnace.It is crucial to grasp the trends of changes in the new permeability index in time.For the complex vibration spectrum of the permeability index,a prediction model of the permeability index based on the VMD-PSO-BP(variational mode decomposition-particle swarm optimization-back propagation)method was proposed.Firstly,the key factors that affect the permeability index of blast furnace were studied from multiple perspectives.Then,the permeability index was divided into multiple sub-modes based on the difference of frequency bands by the VMD algorithm,and a PSO-BP prediction model was established for each sub-mode.Finally,the prediction results of each sub-mode were summed to obtain the final one.The results show that the composite prediction accuracy by using the VMD algorithm is 3%higher than that of the traditional prediction method,which has better applicability.
文摘With the continuous and rapid development of modern ecological environment protection, the key value role of environmental testing has become more and more prominent. How to effectively use diversified environmental testing techniques to comprehensively assist in promoting the high-quality development of environmental protection has attracted much attention in the industry. Based on this, this paper firstly introduces the multi-dimensional value function of environmental testing in environmental protection, analyzes the present situation and existing problems of environmental testing, and combining with the relevant practical experience, respectively, discusses the methods and paths to improve the level of environmental testing and optimize environmental protection from various angles and aspects such as the application of environmental testing information system based on modern science and technology, and expounds some personal opinions on this.
