The most important characteristics of the ultra clean ferritic stainless steel is that the carbon,nitrogen and other interstitial elements are very low.The ultra clean ferritic stainless steel has been widely used for...The most important characteristics of the ultra clean ferritic stainless steel is that the carbon,nitrogen and other interstitial elements are very low.The ultra clean ferritic stainless steel has been widely used for household appliances,auto exhaust system,elevator,water treatment system,building roof and other various fields,because of its low cost,pro-environment,excellent properties.They can replace some traditional austenitic stainless steel.such 304 and 316L.The addition of titanium to liquid steel has become common for stabilizing nitrogen and carbon in steel.Titanium reacts with nitrogen,carbon,and oxygen to form titanium nitride,carbide, carbonitride and oxide.These inclusions may have a deleterious effect on the properties such as toughness, ductility,weldability and corrosion.In addition,the inclusions can also agglomerate and cause surface quality problem of the slab and clogging of the submerged entry nozzle during continuous casting process. The formation rules of inclusions in ultra clean ferritic stainless steel were investigated by the thermodynamic calculation,and methods of controlling inclusions were put forward to improve the quality of product.The composition,type,amount,size and distribution of the inclusions in the slab are investigated by optical microscope and scanning electron microscope.The results can be concluded as follows.(1) In the slab,the main original inclusions,with size of larger than 2μm,are Al_2O_3,TiN or Ti(CN) and complex TiN or Ti(CN) inclusion with core of MgO,MgO-Al_2O_3 and Ti_2o_3,which will not affect the performance of the steel if they are in diffusing distribution.The size of these inclusions are less than 10μm except some Al_2O_3 inclusions in size of 10-40μm.(2) Foreign inclusions are Ti_2O_3-Al_2O_3-MgO-SiO_2 in size above 50μm covered by TiN or Ti (CN).Although these inclusions are few,they do harm to the surface quality of stainless steel.It is able to reduce the risk of forming this kind of inclusion by aluminium deoxidation with increasing Al content to restrain the formation of Ti_2O_3.(3 ) TiN or Ti(CN) is easy to precipitate on inclusions such as MgO,MgO-Al_2O_3 and Ti_2O_3,except Al_2O_3.Controlling the content of[Ti]and[N]and the formation of the oxides can be used to control the precipitation of TiN or Ti(CN).展开更多
This paper deals with the preparatiou of ultra-clean coals by selective oil agglomeration. It has been found that the deashing method used has high deashing rate and high combustible recovery but low oil consumption. ...This paper deals with the preparatiou of ultra-clean coals by selective oil agglomeration. It has been found that the deashing method used has high deashing rate and high combustible recovery but low oil consumption. So it will be widely used in the future. The ash content of coal 1# and 2# is reduced to less than 1%. It has been summarized that the main factors affecting deashing are coal rank, oil consumption, pulp density as well as particle size.展开更多
On the basis of introducing clean power generation technologies, the author calculated and analyzed the investment, economy and environmental protection of these technologies, posed his views of giving the priorities ...On the basis of introducing clean power generation technologies, the author calculated and analyzed the investment, economy and environmental protection of these technologies, posed his views of giving the priorities to the development of supercritical and ultra-supercritical pressure coal-fired power generation technologies and taking vigorous action to nuclear power generation technology within the following 5-10 years, exploiting wind power within the following 10-15 years, and suggested that the installed capacity of nuclear power reach 80-100 GW and that of wind power reach 50-80 GW by 2020.展开更多
Conventional process flow and main work mechanism of alkaline cleaning process of Continual Annealing Line are generally reviewed in the paper,and the work flow of design is analysed including the lye,rinse water circ...Conventional process flow and main work mechanism of alkaline cleaning process of Continual Annealing Line are generally reviewed in the paper,and the work flow of design is analysed including the lye,rinse water circuit,conductivity detection circuit,utility media supply circuit and other main working circuits.Meanwhile,the heat demand of the alkaline cleaning system,rinse water system and dryer device are also analysed.Lumped parameter method in the heat-transfer theory is adopted to calculate the heating time of unsteady heat transfer for strips in the on-line tank.And the reasons why brush roller is of inverse brush and rinsing nozzles are equipped at the inlet side are found.Types and working principles of iron removal and degreasing devices for alkaline cleaning system,which adopt new magnetic filtration and ultra filtration processes,are described.Besides,the bypass filtering method is used to calculate the processing capacity of magnetic filtration and ultra filtration devices.Finally,the related features of 3-Dimension software "PlantSpace" for designing a CAL in Baosteel are totally introduced,such as specification for piping,co-designing,pipe code and 3-Dimension design process.展开更多
文摘The most important characteristics of the ultra clean ferritic stainless steel is that the carbon,nitrogen and other interstitial elements are very low.The ultra clean ferritic stainless steel has been widely used for household appliances,auto exhaust system,elevator,water treatment system,building roof and other various fields,because of its low cost,pro-environment,excellent properties.They can replace some traditional austenitic stainless steel.such 304 and 316L.The addition of titanium to liquid steel has become common for stabilizing nitrogen and carbon in steel.Titanium reacts with nitrogen,carbon,and oxygen to form titanium nitride,carbide, carbonitride and oxide.These inclusions may have a deleterious effect on the properties such as toughness, ductility,weldability and corrosion.In addition,the inclusions can also agglomerate and cause surface quality problem of the slab and clogging of the submerged entry nozzle during continuous casting process. The formation rules of inclusions in ultra clean ferritic stainless steel were investigated by the thermodynamic calculation,and methods of controlling inclusions were put forward to improve the quality of product.The composition,type,amount,size and distribution of the inclusions in the slab are investigated by optical microscope and scanning electron microscope.The results can be concluded as follows.(1) In the slab,the main original inclusions,with size of larger than 2μm,are Al_2O_3,TiN or Ti(CN) and complex TiN or Ti(CN) inclusion with core of MgO,MgO-Al_2O_3 and Ti_2o_3,which will not affect the performance of the steel if they are in diffusing distribution.The size of these inclusions are less than 10μm except some Al_2O_3 inclusions in size of 10-40μm.(2) Foreign inclusions are Ti_2O_3-Al_2O_3-MgO-SiO_2 in size above 50μm covered by TiN or Ti (CN).Although these inclusions are few,they do harm to the surface quality of stainless steel.It is able to reduce the risk of forming this kind of inclusion by aluminium deoxidation with increasing Al content to restrain the formation of Ti_2O_3.(3 ) TiN or Ti(CN) is easy to precipitate on inclusions such as MgO,MgO-Al_2O_3 and Ti_2O_3,except Al_2O_3.Controlling the content of[Ti]and[N]and the formation of the oxides can be used to control the precipitation of TiN or Ti(CN).
文摘This paper deals with the preparatiou of ultra-clean coals by selective oil agglomeration. It has been found that the deashing method used has high deashing rate and high combustible recovery but low oil consumption. So it will be widely used in the future. The ash content of coal 1# and 2# is reduced to less than 1%. It has been summarized that the main factors affecting deashing are coal rank, oil consumption, pulp density as well as particle size.
文摘On the basis of introducing clean power generation technologies, the author calculated and analyzed the investment, economy and environmental protection of these technologies, posed his views of giving the priorities to the development of supercritical and ultra-supercritical pressure coal-fired power generation technologies and taking vigorous action to nuclear power generation technology within the following 5-10 years, exploiting wind power within the following 10-15 years, and suggested that the installed capacity of nuclear power reach 80-100 GW and that of wind power reach 50-80 GW by 2020.
文摘Conventional process flow and main work mechanism of alkaline cleaning process of Continual Annealing Line are generally reviewed in the paper,and the work flow of design is analysed including the lye,rinse water circuit,conductivity detection circuit,utility media supply circuit and other main working circuits.Meanwhile,the heat demand of the alkaline cleaning system,rinse water system and dryer device are also analysed.Lumped parameter method in the heat-transfer theory is adopted to calculate the heating time of unsteady heat transfer for strips in the on-line tank.And the reasons why brush roller is of inverse brush and rinsing nozzles are equipped at the inlet side are found.Types and working principles of iron removal and degreasing devices for alkaline cleaning system,which adopt new magnetic filtration and ultra filtration processes,are described.Besides,the bypass filtering method is used to calculate the processing capacity of magnetic filtration and ultra filtration devices.Finally,the related features of 3-Dimension software "PlantSpace" for designing a CAL in Baosteel are totally introduced,such as specification for piping,co-designing,pipe code and 3-Dimension design process.
