Fused magnesia

Hard-burned magnesias may be used in a variety of appHcations such as ceramics (qv), animal feed supplements, acid neutralization, wastewater treatment, leather (qv) tanning, magnesium phosphate cements, magnesium compound manufacturing, fertilizer, or as a raw material for fused magnesia. A patented process has introduced this material as a cation adsorbent for metals removal in wastewater treatment (132). 

Fused magnesia is primarily utilized as an insulating material in the electrical heating industry. 

Molybdenum has been used with tungsten as a thermocouple for high temperature measurements.1 Such a combination can be used at a much higher temperature than any of the commonly used thermocouples of platinum group metals. Their use is complicated by the fact that to prevent oxidation the metals must be protected with some resistant substance like fused magnesia. 

Due to its excellent corrosion resistance, refractory-grade fused magnesia is used in high wear areas in steelmaking, such as basic oxygen and electric arc... 

Magnesia, caustic-calcined Magnesia clinker Magnesia, dead-burned Magnesia, fused Magnesia oxide fume... 

Dead burned magnesia with chromite Fused magnesia Magnesia-carbon bricks... 

The DPP purging brick consists of fused magnesia of highest quality and high quality graphite, porosity is as low as in other high quality MgO-C bricks used in the EAF walls, 2.9 density is in die very same range. 

Dead-burned magnesias can be used as aggregates as well as matrices for refractory products. Table 1 (15) shows the brand name, country of origin, chemical composition, and bulk density for a number of selected commercial dead-burned magnesias from naturally occurring sources, while Table 2 (16) exhibits the same information for several selected dead-burned synthetic and fused magnesias. 

Tabie 2 T) ical Properties of Several Selected Synthetic Magnesia Sinters (S) and Fused Magnesia Grains (F)... 

Various combinations of magnesia and chrome ore can be produced. The properties of both a typical sintered and a fused magnesia-chrome raw material used for producing a number of different refractory products appear in Table 4 (24). 

Table 4 Properties of Sintered and Fused Magnesia-Chrome Grains...

Some materials have characteristic microstructures that can be used for confirmation of their presence. For instance, fused magnesia, sintered magnesia, and seawater magnesia are structurally different. Similarly, calcined alumina, tabular alumina, and white fused and brown fused alumina all have very different characteristics. 

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