Basic brick

Refractory Linings. The refractory linings (2,3) for the hearth and lower wads of furnaces designed for melting ferrous materials may be acidic, basic, or neutral (see Refractories). Sdica has been widely used in the past, and is stid being used in a number of iron and steel foundries. Alumina, a neutral refractory, is normally used for furnace roofs and in the wads for iron foundries, but basic brick can also be used in roofs (4). 

The resistance against thermal spalling of fireclay and high alumina brick is indicated in Table 5. No standard test has been adopted for basic brick. Refractories composed of 100% magnesia exhibit poor thermal shock resistance, which is improved by addition of chrome ore. So-called direct bonded basic brick, composed of magnesia and chrome additions, exhibits good thermal shock resistance. 

Chemically bonded basic bricks are blended much the same as burned brick mixes except that a bonding agent, eg, magnesium sulfate or magnesium chloride, is added to the mix as well as tempering water to form oxysulfates or oxychlorides. 

Use Refractories, as grains or basic brick, the latter especially in open hearth furnaces for steel, furnaces for nonferrous metal smelting, and in cement and other kilns. 

Table 7.6 Effect of Selective Grinding of Basic Brick on Intensity Ratios and Composition Determination...

In understanding how V2O5 reacts with basic brick, one focuses on the following factors ... 

In basic brick, the bond phases tend to lie at grain boundaries, and it has been shown that mechanical properties deteriorate quickly when liquid forms. The bond phases are crystalline rather than glassy when examined at room temperature. The absence of assy phases in basic brick implies that the liquids that form at elevated temperatures are quite fluid, and the fluidity is likely the reason that mechanical properties deteriorate so readily when liquid is formed. 

Much has been written about how V2O5 from fuel oil can react with CaO in the sUicate minerals in basic brick to produce low melting phases that can increase the prohahUity of checker failures by causing the hot strength and creep resistance of the htick to deteriorate. Less has been written about the reactivity of CaO in the bond phase of basic brick with sodium sulfate that is present in regenerators. 

This paper described some of the principal wear mechanisms of basic refractories used in glass tank regenerators. Alteration of refractories by V2O5 and depletion of CaO from refractories exposed to sodium sulfate was discussed. Alkali attack on forsterite-bonded basic brick was described. Properties of a new type of forsterite-bonded brick that offers the potential for improved performance were presented. 

The case of multiple species undergoing a reaction is worth studying to show how more complex reactions can be modeled from this basic brick. 

D. Gregurek, Investigation of basic and non-basic bricks after the rotary kiln test carried out for Stillwater Mining Company, Columbus, Montana, U.S.A. (Internal RHI report. Technology Center Leoben, Austria, 2012). 

ISO 5019-6 2005 Refractory bricks - dimensions. Part 6 Basic bricks for oxygen steelmaking converters... 

High Alumina Brick High Alumina Brick Burnt Magnesite (Basic Brick)... 

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