Furnace-lining bricks

Anthracite. Anthracite is preferred to other forms of coal (qv) in the manufacture of carbon products because of its high carbon-to-hydrogen ratio, its low volatile content, and its more ordered stmcture. It is commonly added to carbon mixes used for fabricating metallurgical carbon products to improve specific properties and reduce cost. Anthracite is used in mix compositions for producing carbon electrodes, stmctural brick, blocks for cathodes in aluminum manufacture, and in carbon blocks and brick used for blast furnace linings. 

In this process, the feed (natural gas) is pyrolyzed in preheated furnaces lined with a checker work of hot bricks. The pyrolysis reaction produces carbon, which collects on the bricks. The cooled bricks are then... 

The major use (60%) for coloured inorganic pigments, such as iron oxides, is in the construction materials industry. Here they are used to colour roof and flooring tiles, fibrous cement and mortar. Many inorganic pigments are used in coloured baking enamels for metal appliances. Chromium oxide is used in the refractory industry, not for its colour but because of its ability to improve the properties of bricks used in furnace linings. 

Finely divided sodium dichromate (dihydrate or anhydrous) is mixed homogeneously with sulfur. This mixture is then reacted in a furnace lined with refractory bricks at 750-900 °C. An excess of sulfur is used to ensure completion of the reaction. The reaction mass is leached with water to remove water-soluble components such as sodium sulfate. The solid residue is then separated, dried, and ground. 

Carbon pitch is used for carbon electrodes in electrolytic reduction processes, such as aluminum reduction or the production of electro-steels in arc furnaces. Refractory pitch is used in the manufacture of refractory brick, usually burned magnesite or dolomite, the pores of which are filled with pitch by hot impregnation. Upon firing, the pitch in the brick is converted to carbon by carbonization. The remaining pitch coke within the refractory product retards penetration of molten metals and slags, thus prolonging the life of the brick furnace lining. Coke pitch is used in the production of foundry cores. 

The discharge copper-silicon mass can be conducted in a furnace lined with fireproof brick with three horizontal tubular sections placed one above another and fashioned with screws. The baking is conducted at 700... 

This mixture is then reacted in a furnace lined with refractory bricks at 750-900 °C. 

Granular refractories (castables, mouldables, mortars, etc.) serve for the construction of monolithic kiln and furnace linings, for hot and cold repairs, as mortars for the joining of bricks, etc. Essentially, they are mixtures of refractory granular materials with inorganic binders which provide strengthening in situ . 

The reaction is carried out in pot furnaces (low brick-lined hearths with lids), continuous furnaces or rotary plate furnaces. The melt produced in the furnace is mashed with water, the undissolved material removed and the solution concentrated to 60 to 62% sodium sulfide by evaporation in cast iron vessels. This concentrated solution solidifies at ca. 90°C. 

Anhydrous alkali silicates with Si02/alkali oxide > 1.5 (solid glasses) are manufactured by reacting fine particulate quartz sand, which is as pure as possible, is clay-free and has a low iron content, with alkali carbonates or hydroxides at 1300 to 1500°C in tank furnaces lined with refractory bricks or in rotary tube... 

The raw material mixture is melted at ca. 1350°C in tank furnaces lined with chromium oxide and zirconia bricks... 

Magnesite Refractories.—The mineral magnesite, MgCOa, is the source of bjusic refractories used as furnace linings for various metallurgical processes, in the form of bricks or in the crushed state as a mortar and cement for furnace bottoms. The most prominent uses of these materials are in the basic open-hearth furnace and electric-furnace linings. 

COClj-containing brick dust Replacement of reactor furnace lining which had been exposed to COCl2 (AICI3 manufacture) 1 2020... 

Zirkito brick for furnace linings has Itecn on the market for some time. The use of this material futs Iteen greatly stimulated by war conditions, and the results ho far obtained show clearly the importance of zirconin as u refractory. Due to its low coefficient of expansion (linear coefficient of expansion for pure material is 0.00000084 compared to 0.0000007 for quartz), it is especially serviceable in furnaces requiring extreme of temperature with sudden changes, A small experimental furnace lined with zirkite material is reported to have shown no noticeable deterioration after 150 heats of 2-3 hours each at > U, 8. Pan, 1,331,760 (1316) 1.377.0M (IBIS) 1,1 7,663 (1US1). 

OTHER COMMENTS used as an abrasive for cutting and grinding metals used in polishing glass and granite utilized in the manufacture of porcelain, shoe soles, refractor brick, emery paper, and furnace linings used in anti-skid pavements useful in semiconductor technology. 

The aluminosilicate RCF fibers are most widely used in the form of a non-woven blanket or board for furnace linings in the metallurgical, ceramic and chemical industries. An alternative refractory brick would be up to ten times heavier. The use of aluminosilicate felts allows fast heating and cooling cycles of furnaces, because of the reduced mass which has to be heated or cooled and this allows considerable cost savings to be made compared to other types of insulation. 

Silicosis is caused by crystalhne silica in three forms - qttartz, tridy mite and cristo-bahte. The last two are a result of the heating of materials containing quartz, such as bricks in furnace linings. Crystalline sihca causes thickening of the walls of the alveoli and fibrous scar tissue develops. On X-rays this shows as isolated spots which often gradttally spread. It is probable that crystalline sihca may also cause limg cancer in some cases. 

Furnace lining is usually chrome magnesite brick and the life of the refractories is relatively short. Most installations have more than one furnace to allow for downtime for re-bricking. 

AI2O3 Source of aluminum and its compounds Abrasive Refractory bricks and furnace linings Synthetic sapphires and rubies... 

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