Novel Concept of Cleansing the Liquid Steel by the Fine <i>In-Situ</i> Phase due to the Composite Ball Explosion Reaction in RH Ladle

The production of high purity steel is a major task for the iron and steel enterprises in the 21stcentury. To improve the quality of steel products and produce the cleanness steel, the key technique is to control inclusions in the molten steel. In the present investigation, a novel fine inclusion removal technology due to the dispersed in-situ phase induced by the composite ball explosion reaction was put forward. A composite ball with this function has been designed and the industrial experimental investigation was also carried out. The results indicate that feeding composite ball in RH ladle is a novel technology and the inclusion in the molten steel can be removed effectively. Compared with conventional inclusion removal technology, the number of the oxide inclusion can be decreased to a lower level and the inclusion size becomes much finer. Using this novel technology, the total oxygen in the as-cast slab can approach to 6ppm. This novel technology can be achieved without special facility and be realized in most steelmaking plant.

Download Full-text

Investigation on Cleansing the if Molten Steel with the Dispersed In Situ Phase Induced by the Composite Ball Explosive Reaction in RH Ladles

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.284-286.87 ◽

2011 ◽

Vol 284-286 ◽

pp. 87-93

Author(s):

Zhen Li ◽

Xiao Feng Wang ◽

Yang Lin ◽

Peng Fei ◽

Mao Fa Jiang

Keyword(s):

Molten Steel ◽

Oxide Inclusion ◽

Steel Production ◽

Laboratory Model ◽

Cast Slab ◽

Inclusion Removal ◽

Novel Technology ◽

Removal Technology ◽

Explosive Reaction

A novel fine inclusion removal technology due to the dispersed in-situ phase induced by the composite ball explosive reaction was put forward. A composite ball with this function has been designed and prepared using a laboratory model batch type balling disc (at 12 rpm) and the composite ball has been fed at the end of RH refining. The results indicate that feeding composite ball in RH ladle is a novel technology and the inclusion in the IF molten steel can be removed effectively. Compared with conventional inclusion removal technology, the number of the oxide inclusion can be decreased to a lower level and the inclusion size becomes finer. Using this novel technology, the total oxygen in the as-cast slab can approach to 5ppm and the steel production cost for per ton can be reduced by 5 ~12 RMB.

Download Full-text

Industrial experiment study on inclusion evolution in 95CrMo Steel

Metallurgical Research & Technology ◽

10.1051/metal/2019015 ◽

2019 ◽

Vol 116 (5) ◽

pp. 518 ◽

Cited By ~ 1

Author(s):

Linzhu Wang ◽

Junqi Li ◽

Shufeng Yang ◽

Chaoyi Chen ◽

Huixin Jin ◽

...

Keyword(s):

Molten Steel ◽

Single Phase ◽

Oxide Inclusion ◽

Complex Oxides ◽

Inclusion Size ◽

Refining Process ◽

Cooling Process ◽

Sharp Angle ◽

Industrial Experiment ◽

Industrial Experiments

In order to clarify the evolution mechanism of inclusions in 95CrMo, the industrial experiments were conducted. The composition, morphology and size of inclusions during refining and solidifying processes were analyzed by SEM-EDS detection and thermodynamic calculations. The inclusion evolution during refining process in molten 95CrMo steel can be concluded as: Al2O3 → Al2O3-MgO-CaO/CaS → Al2O3-MgO-SiO2-CaO-CaS, which is affected by slag-metal reaction and corrosion of refractory. The change of inclusion size during refining was analyzed based on their collision and floatation behavior. The composition of inclusions in billets indicate that there were mainly five types of inclusions, including spinel with sharp angle, spherical oxide inclusion composed of Al2O3, MgO, SiO2 and CaO, oxide-sulfide inclusion with single phase, inclusion with duplex phase, and MnS inclusion. The type of inclusions affects their size. The thermodynamic results indicate that most complex oxides formed in molten steel and no spinel generated during cooling process. CaS formed in the molten steel after tundish metallurgy and there were still some CaS precipitated in solid steel. MnS precipitated after steel solidification. The calculated results based on FACTSAGE 7.1 are in agreement with experimental results on the whole.

Download Full-text

Simultaneous Desulfurization and Deoxidation of Molten Steel with in Situ Produced Magnesium Vapor

ISIJ International ◽

10.2355/isijinternational.47.418 ◽

2007 ◽

Vol 47 (3) ◽

pp. 418-426 ◽

Cited By ~ 7

Author(s):

Jian Yang ◽

Mamoru Kuwabara ◽

Takao Sakai ◽

Naoyuki Uchida ◽

Zhongzhu Liu ◽

...

Keyword(s):

Molten Steel ◽

Magnesium Vapor

Download Full-text

Temperature Prediction Model for Molten Steel in RH Refining Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.712-715.22 ◽

2013 ◽

Vol 712-715 ◽

pp. 22-25 ◽

Cited By ~ 1

Author(s):

Tia Xia ◽

Zhu He

Keyword(s):

Mathematical Model ◽

Prediction Model ◽

Molten Steel ◽

Initial Temperature ◽

Refining Process ◽

Temperature Prediction ◽

Steel Temperature ◽

Molten Steel Temperature

A mathematical model for the RH refining process was developed and validated by the measured molten steel temperature in situ. It is showed that the model predicted temperature matched the measured value well and the average errors within ±5°C were 86.9%. The model results also showed that for every increase of 100°C of the initial temperature of the chamber inwall , the average molten steel temperature increased by about 8°C. For every blowing extra 50m3 oxygen, the steel temperature increased by about 7°C.

Download Full-text

Origin of non-cotectic cumulates: A novel approach

Geology ◽

10.1130/g47082.1 ◽

2020 ◽

Vol 48 (6) ◽

pp. 604-608 ◽

Cited By ~ 2

Author(s):

R.M. Latypov ◽

S.Yu. Chistyakova

Keyword(s):

Phase Equilibria ◽

Basaltic Magma ◽

Parental Magma ◽

Magma Chambers ◽

Mechanical Mixing ◽

Novel Approach ◽

In Situ Crystallization ◽

Mechanical Separation ◽

Novel Concept

Abstract Plutonic mafic complexes are composed of cumulates in which minerals mostly occur in cotectic proportions. This is consistent with a concept that basaltic magma chambers predominantly crystallize in situ from margins inward. However, cumulates with two (or more) minerals in proportions that are at odds with those expected from liquidus phase equilibria also locally occur in these complexes. Such non-cotectic cumulates are commonly attributed to either mechanical separation of minerals crystallizing from the same parental magma or mechanical mixing of minerals originating from different parental magmas. Here we introduce a novel concept that does not require any of these processes to produce non-cotectic cumulates. The model involves melts that start crystallizing upon their cooling, while ascending along feeder conduits from deep staging reservoirs toward the Earth’s surface. Depending on the degree of cooling, the melts become successively saturated in one, two, and more liquidus phases. Given that most crystals are kept in suspension, the resulting magmas would contain a cargo of equilibrium phenocrysts in notably non-cotectic proportions. The replenishment of basaltic chambers developing through in situ crystallization by such magmas is likely responsible for the occasional formation of non-cotectic cumulates in plutonic mafic complexes.

Download Full-text

A Novel Technology for Green(er) Manufacturing of CNTs via Recycling of Waste Plastics

MRS Proceedings ◽

10.1557/opl.2011.139 ◽

2011 ◽

Vol 1317 ◽

Cited By ~ 3

Author(s):

Chuanwei Zhuo ◽

Brendan Hall ◽

Yiannis Levendis ◽

Henning Richter

Keyword(s):

Stainless Steel ◽

Low Cost ◽

Waste Plastics ◽

Waste Plastic ◽

Solid Polymers ◽

Carbon Supply ◽

Novel Technology ◽

Multi Stage ◽

Waste Solid

ABSTRACTCostly and often highly-flammable chemicals, such as hydrogen and carbon-containing gases, are largely used for carbon supply in current carbon nanotube (CNT) synthesis technologies. To mitigate related economic and safety concerns, we have developed a versatile CNT synthesis sequence, where low-cost and safe-to-handle-and-store waste solid polymers (plastics) are used for in situ generation of hydrogen and carbon-containing gases. Introduction of different waste plastics, such as polyethylene, polypropylene and polystyrene, into a multi-stage pyrolysis/ combustion/synthesis reactor allows for efficient CNT formation. This process is largely exothermic and scalable. It uses low-cost stainless steel screens to serve both as substrates as well as catalysts for CNT synthesis. This technique enables a solution for both waste plastic utilization and sustainable CNT production.

Download Full-text

Effects of Rare Earth Chlorides on Properties of Al2O3-MgO Castables

Materials Science Forum ◽

10.4028/www.scientific.net/msf.848.283 ◽

2016 ◽

Vol 848 ◽

pp. 283-288 ◽

Cited By ~ 1

Author(s):

Wen Jie Yuan ◽

Bi Hui Kuang ◽

Qing You Zhu ◽

Cheng Ji Deng ◽

Hong Xi Zhu

Keyword(s):

Rare Earth ◽

High Performance ◽

Positive Influence ◽

Modulus Of Rupture ◽

Cerium Chloride ◽

Linear Change ◽

Iron And Steel ◽

Steel Making ◽

Yttrium Chloride

For the urgent requirements of high performance castables in iron and steel making industry, effects of rare earth chlorides on properties of Al2O3-MgO castables were addressed. The prepared castables were compared in terms of phase compositions, apparent porosity, bulk density, permanent linear change and strength. It was demonstrated that cerium chloride and yttrium chloride exhibited a positive influence on in-situ reactions and volumetric stability of castables. The cation inversion degree of spinel and solid-soluted content of spinel and CaAl12O19 (CA6) were both dependent on the temperature and addition. Cold modulus of rupture for castbles with rare earth chlorides additions calcined at 1450°C was similar to that for referenced castables though the former ones were relatively less at 1250 and 1350°C.

Download Full-text