Blast Furnace Steel Research Articles

Mutual Influence of Special Components in Baotou Steel Blast Furnace Slag on the Crystallization Behavior of Glass

In the process of glass-ceramics prepared with Baotou steel blast furnace slag, quartz sand, and other raw materials by melting method, the mutual influence of the special components such as CaF2, REXOY, TiO2, K2O, and Na2O in the blast furnace slag on the crystallization behavior of parent glass was investigated using differential thermal analysis (DTA) and X-ray diffraction (XRD). The results show that the special components in slag can reduce the crystallization temperature and promote crystallization of glass phase, which belongs to surface crystallization of glass, and they cannot play the role of the nucleating agent; the major crystal phase composed of diopside, diopside containing aluminum and anorthite, is slightly different from the expected main crystal phase of diopside. Therefore, the nucleating agents of proper species and quantity must be added into the raw materials in order to obtain glass-ceramics. The results have important theoretical guidance meaning for realizing industrial production of Baotou steel blast furnace slag glass-ceramics preparation.

Production of iron and oxygen in molten K 2CO 3–Na 2CO 3 by electrochemically splitting Fe 2O 3 using a cost affordable inert anode

Iron oxide was electrochemically split into iron and oxygen gas in molten Na 2CO 3–K 2CO 3 at 750 °C using a solid iron oxide cathode and a Ni10Cu11Fe alloy inert anode. Fe 2O 3 was electrochemically reduced to Fe on the cathode, releasing oxygen anions into the electrolyte and which were oxidized on the anode to generate O 2. The cathodic current efficiency was as high as 95% and the energy consumption for producing 1 kg iron was 2.87 kWh, only half of the current industrial energy consumption of blast-furnace steel production. Due to the cost-affordable inert anode and the high energy efficiency, the method demonstrated in this work shows promise as a practical “green” iron production process.

Analysing blast furnace data using evolutionary neural network and multiobjective genetic algorithms

Approximately one year's operational data of a TATA Steel blast furnace were subjected to a multiobjective optimisation using genetic algorithms. Data driven models were constructed for productivity, CO2 content of the top gas and Si content of the hot metal, using an evolutionary neural network that itself evolved through a multiobjective genetic algorithm as a tradeoff between the accuracy of training and the network complexity. The final networks were selected using the corrected Akaike information criterion. Bi-objective optimisation studies were subsequently carried out between the productivity and CO2 content with various constraints at the Si level in the hot metal. The results indicate that a productivity increase would entail either a compromise of the CO2 fraction in the top gas or the Si content in the hot metal. The Pareto frontiers presented in this study provide the best possible parameter settings in such a scenario.

Heat transfer analysis of blast furnace cast steel cooling stave

Cast steel blast furnace (BF) cooling staves are widely used in the Chinese steel industry. A heat transfer mathematical model of a BF cast steel cooling stave has been developed and verified by thermal state experiments. Calculation of a cooling stave working under steady state has been carried out based on the model. Effects of two factors, thickness of scale on the cooling water pipes and gas clearance between the pipes and main body, which are difficult for experimental measurement but determined mathematically, on the temperature field of the stave body are discussed. The results indicate that much importance should be attached to the two factors during manufacturing of cooling staves as they highly influence cooling capability of cooling stave and hence BF operation.

EXPERIMENTAL STUDY ON MECHANICAL PROPERTIES OF WELDED JOINT USING VIBRATORY CONDITIONING TECHNOLOGY

The vibratory welding conditioning process is investigated in the electroslag welding of blast furnace steel. The metallographs show that a refined joint is produced. The residual stress, side bend property, tension and impact tests are carried out in different vibratory conditions (0g, 0.3g and 0.6g). The results of the test have fully proved that vibratory conditioning technology can effectively reduce residual stress and improve the comprehensive properties of weld joints. Especially, in the 0.6g vibratory condition, the qualification rate of side bend performance is up to 100%. The impact values at two vibratory accelerations (0.3g and 0.6g) are compared and the changing mechanism is discussed. The internal friction test indicates that the internal friction SKK (Snoek-Ke-Koster) peak of the weld metal has good correlation with the impact value of the weld.

Investigation of combustion behavior of a PCI coal and unburnt char carryover in a US Steel blast furnace

Investigation of combustion behavior of a PCI coal and unburnt char carryover in a US Steel blast furnace

Improving slurry seal performance in Eastern Saudi Arabia using steel slag

Harsh climate, heavy traffic and, most importantly, use of low-quality aggregates have resulted in unsatisfactory slurry seal performance in the eastern region of Saudi Arabia. On the other hand, blast furnace steel slag, a superior aggregate type with excellent strength and surface properties, is being wasted as a by-product during the steel manufacturing process. This research was carried out to assess and improve the performance of slurry seal mixtures in the laboratory using the Aggregate Blend Improvement Technique by incorporating steel slag aggregate. Aggregate blends consisting of slag and limestone were evaluated to form an improved slurry seal mixture that will generate simultaneously greater wear-resistance and improved bonding characteristics with bitumen. Results indicate that significant improvements in mixtures are guaranteed through improved aggregate blending of slag with limestone.

鉄筋コンクリート用棒鋼のシャルピー衝撃特性に及ぼす諸因子の影響

The reinforcing steel bars which are one of the structural rolled steels for construction can be classified into two types as blast furnace reinforcing steel bars and electric furnace reinforcing steel bars. Electric furnace reinforcing steel bars are utilized for about 85 per cent of all reinforcing steel bars at present.In this study, firstly, the Charpy impact characteristics of the above-mentioned two types of material SD35 were investigated.Secondly, the correlations between the Charpy impact characteristics and various factors such as chemical compositions, rolling conditions, and optical microstructures were studied using the multiple regression analysis method.As a result, the apparent differences in Charpy impact characteristics were found between the two types of bars. That is to say, the electric furnace steel bars had energy transition curves or fracture transition curves with more gentle slopes, lower shelf energies (vEshelf), and higher energy ransition temperatures (vErE) or higher fracture transition temperatures (vTrs) than the blast furnace steel bars. Therefore, it has been realized that these differences in characteristics depend on Mn, Cr and N Contents as well as on reduction ratio. It has also been realized that vTrE and vTrs shift to lower temperatures as the ferrite perlite structures become lamellar.

753. Vacuum melted special alloys for aerospace applications: R P Simmons and RK Pilter,Blast Furnace Steel Plant, 55 (8), Aug 1967, 706–712

753. Vacuum melted special alloys for aerospace applications: R P Simmons and RK Pilter,Blast Furnace Steel Plant, 55 (8), Aug 1967, 706–712

878. A decade of vacuum degassing at US Steel Corporation: C J Hunter and J N Hornak, Blast Furnace Steel Plant, 33, Aug 1965, 699–703

878. A decade of vacuum degassing at US Steel Corporation: C J Hunter and J N Hornak, Blast Furnace Steel Plant, 33, Aug 1965, 699–703