Computational Modeling of Blast Furnace Stave Cooler Based on Steady State Heat Transfer Analysis

et al. 2023

steel research int.

The blast furnace tuyere is a crucial component for blast furnace production. The frequent damage of the copper tuyere impedes the smooth operation of the blast furnace. Welding a wear‐resistant layer on the tuyere can extend its service life, but it still falls short of the expectation in a large blast furnace. This paper aims to elucidate the erosion mechanism of the wear‐resistant layer. A scanning electron microscope (SEM), an energy dispersive spectrometer (EDS), and an optical microscope (OM) were employed to examine the morphology, composition, and metallographic structure of the samples obtained from a 5800m3 blast furnace tuyere in China, as well as to calculate the frequency of daily slag crust shedding from cooling staves. The results indicate that the main cause of the erosion of the wear‐resistant layer is the shedding of slag crust due to the temperature fluctuation of the cooling staves. Finally, the erosion mechanism of the wear‐resistant layer is proposed. It is suggested that the formation and propagation of cracks caused by erosion of slag and hot metal are the primary failure mode of the wear‐resistant layer.This article is protected by copyright. All rights reserved.

Section: Analysis Of the Reason For The Erosion Of The Wear-resistant...mentioning

confidence: 99%

Analysis of Erosion Mechanism of Wear‐Resistant Layer in Large Blast Furnace Tuyere

Zhou

et al. 2023

steel research int.

“…The BF has adapted overall cooping structure which eliminates the blind region of the cooling system in BF [8]. From the bottom of the furnace to the throat, complete coolers were set according to the working conditions of each part and the full coverage cooling system of the whole BF body is constructed [9]. The cooling structure has bloomed into the cooling plate, cooling stave and plate-stave combined cooling structure and there are more choices for materials of coolers, for instance, copper, ductile iron, cast steel [10].…”

Section: Introductionmentioning

confidence: 99%

A new method for evaluating cooling capacity of blast furnace cooling stave

Jiao

Ironmaking & Steelmaking

et al. 2018

The detailed process of the heat transfer of the cooling stave in blast furnace (BF) has been systematically analyzed and the simplified mathematical model was constructed based on heat transfer theory. Precise definitions of the cooling capacity, stable working slag thickness and safe working slag thickness were put forward so as to evaluate the cooling capacity of cooling stave systematically. The results show that 95% of heat is carried off by cooling water through convection and the heat taken away through convective heat transfer between furnace shell and atmosphere only account for 5%. The entire heat transfer process can be divided into four modules and the cooling system is divided into three parts. The cooling capacity ⍰ is defined and function curve of temperature of cooling stave hot surface T b with changes of brick thickness is drawn and the safe working area and stable working area are put forward.

“…The super cooling capacity of cooling staves is the key to the formation of stable slag crusts [5]. Compared to previously used cast iron cooling staves, copper cooling staves are better thermal conductors because of their good thermal conductivity, thermal shock properties, and heat carrying capacity [6][7][8]. Therefore, copper staves have become a major development model to decrease the cost of iron making and extend the campaign lives [9][10][11].…”

Section: Introductionmentioning

confidence: 99%

Damage Mechanism of Copper Staves in a 3200 m3 Blast Furnace

Zuo

Wang

2018

Metals

Copper staves have been widely applied in large blast furnaces especially those whose inner volumes exceed 2000 m3 due to high cooling capacity. In the past decade, copper staves suffered severe damages in some blast furnaces, which not only shortened their campaign lives, but also caused huge economic losses. In order to make out this phenomenon, the damage mechanism of copper staves was investigated via analyzing the chemical composition, thermal conductivity, metallographic aspects and microstructure in this paper. As a result, the working state was more likely to damage copper staves instead of their materials. At the beginning, the poor quality of the coke and the large bosh angle promoted the development of edge airflow, which intensified the erosion of refractory materials, resulting in the fall-off of slag crusts and damage of cooling water pipes. After repair, the cooling capacity of copper staves still declined, causing the temperature to rise easily; consequently, hydrogen attack happened when the temperature reached 370 °C, which degraded the performance of copper staves. Therefore, copper staves were worn too quickly to form slag crusts, which finally failed under the hydrogen attack and the scouring of the edge airflow at high temperatures.