Discussion on the Decomposition Laws of Limestone during Converter Steelmaking Process by Static Decomposition Model under Constant Temperature

Variations of decomposition rate and decomposition layer thickness of six spherical limestone particles with different sizes are calculated and compared with each other by the experiments and model of static decomposition of limestone under constant temperature. The results indicate that: the decomposition process of limestone can be explained by unreacted core model (UCM) when it is heated sharply; the decomposition rate of large particle is greater than that of small one; the smaller particle size, the larger decomposition layer thickness in unit time.

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Research on Using Limestone for Slagging during BOF Steelmaking Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.690-693.237 ◽

2013 ◽

Vol 690-693 ◽

pp. 237-245 ◽

Cited By ~ 6

Author(s):

Jia Feng ◽

Hong Li ◽

Chen Xiao Li ◽

Wen Chen Song ◽

Wu Nian ◽

...

Keyword(s):

Low Temperature ◽

High Speed ◽

Early Stage ◽

Converter Steelmaking ◽

Steelmaking Process ◽

Hot Metal ◽

Primary Research ◽

High Basicity ◽

Unreacted Core ◽

Unreacted Core Model

This paper introduced the primary research on the method of using limestone instead of lime for slagging during BOF steelmaking. The study showed that the heat is sufficient for limestone to completely replace lime on the condition that the ratio of hot metal to ferrous scrap is adjusted properly. According to thermodynamic calculations, the partial pressure of CO2 at the hot metal surface at the early stage of converter steelmaking is close to 0 and nearly all the CO2 can react with elements in hot metal, producing CO and reducing O2 consumption. Slag with high oxidizability, high basicity and relatively low temperature can be formed quickly by using limestone, which is advantageous for dephosphorization. Industrial tests showed the endpoint Lp rises with the proportion of lime replaced by limestone increasing. CO2 volume expands by 4000~30000 times when limestone is heated at extremely high speed in converter, resulting in the fragmentation of some parts of limestone and the increase of the contacting area of limestone and slag. The unreacted core model with surface exfoliated was introduced.

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Oxidation and reduction characteristics of oxygen carrier particles and reaction kinetics by unreacted core model

Korean Journal of Chemical Engineering ◽

10.1007/bf02705604 ◽

2001 ◽

Vol 18 (6) ◽

pp. 831-837 ◽

Cited By ~ 85

Author(s):

Ho-Jung Ryu ◽

Dal-Hee Bae ◽

Keun-Hee Han ◽

Seung-Yong Lee ◽

Gyoung-Tae Jin ◽

...

Keyword(s):

Reaction Kinetics ◽

Oxygen Carrier ◽

Core Model ◽

Unreacted Core ◽

Unreacted Core Model ◽

Reduction Characteristics

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Behavior of Gas–Slag–Metal Emulsion with Nozzle–Twisted Lance in Converter Steelmaking Process

steel research international ◽

10.1002/srin.202100103 ◽

2021 ◽

Author(s):

Ming Lv ◽

Hang Li ◽

Tengchang Lin ◽

Kun Xie ◽

Kui Xue

Keyword(s):

Converter Steelmaking ◽

Steelmaking Process

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Effect of Sintering Properties on Large Particle Size of Ni Power for MLCs with Ni Internal Electrode.

Journal of the Ceramic Society of Japan ◽

10.2109/jcersj.109.1275_963 ◽

2001 ◽

Vol 109 (1275) ◽

pp. 963-967

Author(s):

Ryosuke UEYAMA ◽

Tamotsu UEYAMA ◽

Kunihito KOUMOTO

Keyword(s):

Particle Size ◽

Large Particle ◽

Large Particle Size ◽

Internal Electrode ◽

Sintering Properties

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A SIMULATION STUDY ON THE EFFECT OF PARTICLE SIZE DISTRIBUTION ON THE PRINTED GEOMETRY IN SELECTIVE LASER MELTING

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4052705 ◽

2021 ◽

pp. 1-14

Author(s):

Vaishak Ramesh Sagar ◽

Samuel Lorin ◽

Johan Göhl ◽

Johannes Quist ◽

Christoffer Cromvik ◽

...

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Layer Thickness ◽

Selective Laser Melting ◽

Laser Melting ◽

Powder Bed ◽

Mean Particle Size ◽

Final Layer ◽

Effect Of Particle Size

Abstract Selective laser melting (SLM) process is a powder bed fusion additive manufacturing process that finds applications in aerospace and medical industries for its ability to produce complex geometry parts. As the raw material used is in powder form, particle size distribution (PSD) is a significant characteristic that influences the build quality in turn affecting the functionality and aesthetics aspects of the product. This paper investigates the effect of PSD on the printed geometry for 316L stainless steel powder, where three coupled in-house simulation tools based on Discrete Element Method (DEM), Computational Fluid Dynamics (CFD), and Structural Mechanics are employed. DEM is used for simulating the powder bed distribution based on the different powder PSD. The CFD is used as a virtual testbed to determine thermal parameters such as heat capacity and thermal conductivity of the powder bed viewed as a continuum. The values found as a stochastic function of the powder distribution is used to analyse the effect on the melted zone and deformation using Structural Mechanics. Results showed that mean particle size and PSD had a significant effect on the packing density, melt pool layer thickness, and the final layer thickness after deformation. Specifically, a narrow particle size distribution with smaller mean particle size and standard deviation produced solidified final layer thickness closest to nominal layer thickness. The proposed simulation approach and the results will catalyze in development of geometry assurance strategies to minimize the effect of particle size distribution on the geometric quality of the printed part.

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