What refractory is used in a blast furnace?

What refractory is used in a blast furnace?

Normally, the refractory lining of the conventional blast furnace is made by carbon or graphite blocks. Carbon and graphite is ideal for this particular application because both of them are not wet by hot metal. These refractories has low interfacial tension with the mixture hot metal/ liquid slag.

What refractories are used in steelmaking?

Fireclay and high alumina refractories are used. Most of the continuous furnaces are lined with fireclay bricks. Plastic chrome ore ramming mixture and hard burnt chrome magnesite bricks are used to line the hearth to provide resistance to scale.

Which property of refractories is the most important for top section of the blast furnace?

Question 34 : Which property of refractories is the most important for top section of the blast furnace? Resistance to abrasion.

What is trough in blast furnace?

Page 1. BLAST FURNACE TROUGH. MATERIALS (TROUGH MIX) The flow rate of molten metal and slag through the trough system increase many times in case of larger blast furnaces. To get good campaign life special attention must be given to both refractory lining and design i.e. trough geometry and cooling system.

What are blast furnaces lined with?

The purpose of a blast furnace is to chemically reduce and physically convert iron oxides into liquid iron called “hot metal”. The blast furnace is a huge, steel stack lined with refractory brick, where iron ore, coke and limestone are dumped into the top, and preheated air is blown into the bottom.

What material is used to lined the heart of the furnace?

Normally, the refractory lining of the conventional blast furnace is made by carbon or graphite blocks. Carbon and graphite is ideal for this particular application because both of them are not wet by hot metal.

What types of refractories are utilized in the BF and BOF furnace construction?

The refractories available for use in wear linings of BOF range from tar or pitch bonded dolomite or magnesia (MgO), chrome magnesite, or magnesium chrome refractories to the advanced refractories that are made with resin bonds, metallics, graphites, and sintered and/or fused magnesia that can be with a purity of 99 \%.

What is the thickness of refractory lining in BOF?

This consist of a thinner safety lining to protect the shell usually of thickness ranging from 150 mm to 225 mm and a thicker working lining usually of thickness ranging from 450 mm to 750 mm.

What are the criteria for a good refractory?

A good refractory should have high RUL value. It is defined as the ratio of its pore volume to the bulk volume. Porosity is an important property of refractory bricks, because it affect many other characteristics like chemical stability, strength, abrasion- resistance and thermal conductivity.

Which one of the following refractories Cannot be used in oxidizing conditions?

Zirconia is used when the material is required to withstand extremely high temperatures. Silicon carbide and carbon are two other refractory materials used in some very severe temperature conditions, but they cannot be used in contact with oxygen, since they oxidize and burn in atmospheres containing oxygen.

Why is coke used in a blast furnace?

Coke is added to the top of the furnace and provides support for the burden- the iron ore, limestone, sinter, and perhaps turnings that are charged. That stability and the porosity are important to let the hot blast permeate and form CO and reduce the iron oxide to pure iron. Coke is a support material.

Does a blast furnace use more coal?

The Blast Furnace is a members-only minigame situated in Keldagrim for smelting bars. The furnace here only requires half as much coal when smelting usually, so it can be useful when smelting the ores that require more coal.

Why are blast furnaces refractory lined?

A modern blast furnace (BF) is refractory lined to protect the furnace shell from the high temperatures and abrasive materials inside the furnace. The refractory lining is cooled to further enhance the protection against the dispatch of excess heat that can destroy the refractory lining.

What factors determine the campaign life of a blast furnace?

Lining is the most important factor for determining the campaign life of a blast furnace. The cooling of refractory lining is the most contributing factor in deciding the Furnace campaign life. Lining cooling by stave technology is one of the products of such efforts.

What is the heat transfer model in blast furnace?

The three dimensional model of heat transfer of cooling stave with refractory lining in a blast furnace are modelled and analyzed with the help of ANSYS software. The model further utilized for the heat transfer analysis of different thickness of lining materials.

Why do we need refractory lining for Bf?

Operational factors such as (i) high productivity leading to high heat loads, (ii) high fluid velocity that causing more erosion and (iii) high coal injection means lower permeability. None of these factors are under the control of BF operator and hence, the only solution for this can be a robust refractory lining.