It is of great importance for obtaining the perfect welding properties to control the acicular ferrite (AF) transformation behavior reasonably in steel weld. AF continuous transformation kinetics in the HSLA steel wel...It is of great importance for obtaining the perfect welding properties to control the acicular ferrite (AF) transformation behavior reasonably in steel weld. AF continuous transformation kinetics in the HSLA steel weld was calculated and modeled based on the direct growth on the inclusions inert interface. The simulation results are coincident with the experimental value well.展开更多
The effective utilization of steel slag, a byproduct produced in large quantities from the steel refining process, is an important issue. Because steel slag contains abundant mineral components, the effects of steel s...The effective utilization of steel slag, a byproduct produced in large quantities from the steel refining process, is an important issue. Because steel slag contains abundant mineral components, the effects of steel slag on soil bacterial biomass and plant mineral uptake were analyzed in this study. The soil pH increased in proportion to the amount of steel slag added. A lower concentration (0.2% to 1%) of steel slag addition did not change the bacterial biomass. However, a higher concentration of steel slag (above 1%) had a negative effect on bacterial biomass. A lower amount of steel slag (0.2% to 1%) addition in soil leads to increased mineral (Ca, Mg, and Fe) uptake and plant growth in Brassica rapa var. periviridis and Spinacia oleracea L. However, mineral uptake by the plants decreased when a large amount of steel slag (above 1%) was added to the soil. Low concentrations of steel slag (0.2% to 1%) in soil had positive effects on plant growth, mineral uptake of plants, and bacterial biomass.展开更多
Japan started the national project“COURSE 50”for CO_(2) reduction in the 2000s.This project aimed to establish novel technologies to reduce CO_(2) emissions with partially utilization of hydrogen in blast furnace-ba...Japan started the national project“COURSE 50”for CO_(2) reduction in the 2000s.This project aimed to establish novel technologies to reduce CO_(2) emissions with partially utilization of hydrogen in blast furnace-based ironmaking by 30%by around 2030 and use it for practical applications by 2050.The idea is that instead of coke,hydrogen is used as the reducing agent,leading to lower fossil fuel consumption in the process.It has been reported that the reduction behavior of hematite,magnetite,calcium ferrite,and slag in the sinter is different,and it is also considerably influenced by the sinter morphology.This study aimed to investigate the reduction behavior of sinters in hydrogen enriched blast furnace with different mineral morphologies in CO-CO_(2)-H2 mixed gas.As an experimental sample,two sinter samples with significantly different hematite and magnetite ratios were prepared to compare their reduction behaviors.The reduction of wustite to iron was carried out at 1000,900,and 800℃ in a CO-CO_(2)-H2 atmosphere for the mineral morphology-controlled sinter,and the following findings were obtained.The reduction rate of smaller amount of FeO led to faster increase of the reduction rate curve at the initial stage of reduction.Macro-observations of reduced samples showed that the reaction proceeded from the outer periphery of the sample toward the inside,and a reaction interface was observed where reduced iron and wustite coexisted.Micro-observations revealed three layers,namely,wustite single phase in the center zone of the sample,iron single phase in the outer periphery zone of the sample,and iron oxide-derived wustite FeO and iron,or calcium ferritederived wustite'FeO'and iron in the reaction interface zone.A two-interface unreacted core model was successfully applied for the kinetic analysis of the reduction reaction,and obtained temperature dependent expressions of the chemical reaction coefficients from each mineral phases.展开更多
基金the financial support of this research by the Youth Scientist Innovation Foundation of Petroleum Science and Technology(Grant No.2002CX05)by A Foundation for the Author of National Excellent Doctoral Dissertation of P.R.China(Grant No.200233)by the National SCience Foundation of China(Grant No.50334050).
文摘It is of great importance for obtaining the perfect welding properties to control the acicular ferrite (AF) transformation behavior reasonably in steel weld. AF continuous transformation kinetics in the HSLA steel weld was calculated and modeled based on the direct growth on the inclusions inert interface. The simulation results are coincident with the experimental value well.
文摘The effective utilization of steel slag, a byproduct produced in large quantities from the steel refining process, is an important issue. Because steel slag contains abundant mineral components, the effects of steel slag on soil bacterial biomass and plant mineral uptake were analyzed in this study. The soil pH increased in proportion to the amount of steel slag added. A lower concentration (0.2% to 1%) of steel slag addition did not change the bacterial biomass. However, a higher concentration of steel slag (above 1%) had a negative effect on bacterial biomass. A lower amount of steel slag (0.2% to 1%) addition in soil leads to increased mineral (Ca, Mg, and Fe) uptake and plant growth in Brassica rapa var. periviridis and Spinacia oleracea L. However, mineral uptake by the plants decreased when a large amount of steel slag (above 1%) was added to the soil. Low concentrations of steel slag (0.2% to 1%) in soil had positive effects on plant growth, mineral uptake of plants, and bacterial biomass.
基金based on results obtained from the“CO_(2)Ultimate Reduction System for Cool Earth 50(COURSE50)Project”commissioned by the New Energy and Industrial Technology Development Organization(NEDO)。
文摘Japan started the national project“COURSE 50”for CO_(2) reduction in the 2000s.This project aimed to establish novel technologies to reduce CO_(2) emissions with partially utilization of hydrogen in blast furnace-based ironmaking by 30%by around 2030 and use it for practical applications by 2050.The idea is that instead of coke,hydrogen is used as the reducing agent,leading to lower fossil fuel consumption in the process.It has been reported that the reduction behavior of hematite,magnetite,calcium ferrite,and slag in the sinter is different,and it is also considerably influenced by the sinter morphology.This study aimed to investigate the reduction behavior of sinters in hydrogen enriched blast furnace with different mineral morphologies in CO-CO_(2)-H2 mixed gas.As an experimental sample,two sinter samples with significantly different hematite and magnetite ratios were prepared to compare their reduction behaviors.The reduction of wustite to iron was carried out at 1000,900,and 800℃ in a CO-CO_(2)-H2 atmosphere for the mineral morphology-controlled sinter,and the following findings were obtained.The reduction rate of smaller amount of FeO led to faster increase of the reduction rate curve at the initial stage of reduction.Macro-observations of reduced samples showed that the reaction proceeded from the outer periphery of the sample toward the inside,and a reaction interface was observed where reduced iron and wustite coexisted.Micro-observations revealed three layers,namely,wustite single phase in the center zone of the sample,iron single phase in the outer periphery zone of the sample,and iron oxide-derived wustite FeO and iron,or calcium ferritederived wustite'FeO'and iron in the reaction interface zone.A two-interface unreacted core model was successfully applied for the kinetic analysis of the reduction reaction,and obtained temperature dependent expressions of the chemical reaction coefficients from each mineral phases.
