Refractory application

To ensure a high quality refractory application, the refiner must require the following ... 

To ensure longer service life for the refractory application, a thorough dryout procedure should be implemented and practiced. Slow thermal dryout is required to minimize and eliminate refractory spalling. 

Uses. Chemical intermediate for magnesium salts component of pharmaceuticals, cosmetics, dentifrices, free-running table salt agent in heat insulation and refractory applications... 

Rao, R. B., Chattopadhyay, P. Banerjee, G. N. 1999. Removal of iron from fly ash for ceramic and refractory applications. Magnetic and Electrical Separation, 10, 21-27. 

The production of flame retardant quahty aluminium hydroxide has recently been reviewed [98]. Various crystal forms of aluminium hydroxide exist, but that used for polymer appHcations is Gibbsite. This occurs widely in nature, usually in the rock bauxite, but the natural form is usually not suitable for direct use and synthetic products are nearly always employed. Most aluminium hydroxide is manufactured through the Bayer process used to make alumina for refractory applications. 

For refractory applications, when the mixed oxide route is followed, temperatures as high as 1900 °C are necessary to sinter to high density. The high interest in SOFCs has stimulated efforts to develop novel fabrication routes to zirconia ceramics and yttria-stabilized sub-micron sized powders have been prepared which sinter to 95% theoretical density at a temperature as low as 1150 °C [4],... 

Conversion is of only minor importance for the use of calcium aluminate cements in refractory applications and in mixes with Portland cement such as those described in Section 10.1.10. 

Volkmann, D. and Just, T., Refractories for Gasification Reactors A Gasification Technology Supplier s Point of View, Refractories Applications and News, 9, 11-16, 2004. 

Thorium Monazite [(REE,Th)P04] byproduct from heavy-mineral sands Refractory applications catalyst... 

For these reasons, various manufacturers supply a number of various types of calcined AI2O3 differing in purity, particle size and other parameters. Each of these types is designed for a special, clearly specified purpose, and the guarantees include maintenance of all the properties significant for a particular utilization. Firing treatment at temperatures up to 2000 °C is used to produce coarse tabular crystals for refractory applications (so-called tabular alumina). 

Bennett, J.P. Refractory liner materials used in slagging gasifiers. Refractory Applications, 2004, 9, 20-25. 

Use Oxidation-resistant coatings, electrical resistance and refractory applications. 

CarboTherm (seven grades of different particle sizes for refractory applications)... 

With a low thermal conductivity of 0.06 W cm-1 K 1 and a low thermal expansion coefficient a 4.5 x 10 6oC 1, mullite is useful for many refractory applications [49], According to Schneider, most mullites display low and nonlinear thermal expansions below, but larger and linear expansion above, 300°C. The volume thermal expansion... 

Aluminate compositions include calcium aluminate cements, which have high chemical resistance, especially to sulfate, and is also used in refractory applications where ordinary Portland cements would be unsuitable. These same cements are used in bioceramic applications. The bioceramic applications reflect both the high mechanical strength of the calcium aluminate cements and also the biocompatibility of Ca-bearing phases, which bond well with, for example, bone. 

Historically, most of the oxides that were used in refractory applications were traditional ceramics prepared from clays or other readily available mineral-based raw materials. The major categories of traditional refractories are fire clays, high aluminas, and silica [1], The choice of material for traditional refractory applications, as with advanced material applications, was and is based on balancing cost and performance/lifetime. The ultimate use temperatures and applications for some common refractories are summarized in Table 1 [2, 3], The production, properties, and uses of some of these materials are discussed in more detail in the other chapters... 

Refractories Applications News, published by the University of Missouri-Rolla http //www. ranews.info. 

Dead-burned magnesia is used almost exclusively for refractory applications, primarily in brick and basic granular refractories. The essential qualities of dead-burned magnesite that make it suitable for refractory applications are that it has a very high melting point (2800°C), it does not oxidize, and it has excellent resistance to attack by iron oxide, alkalis, and... 

HAC is used where rapid strength gain is required, in refractory applications and, with calcium sulfate, to form ettringite-based products either for shrinkage compensation or for high waterxement ratio grouts (e.g., 5 1). It is important to control carefully the relative proportions of HAC and calcium sulfate in ettringite-based systems to ensure optimum properties. 

Insulation. Micrometer-sized pores in composite foams, together with their extremely low density, minimize conductive heat transfer. Addition of a small amoimt of fibers provides some rigidity to the foam. It is easy to visualize that a structin-e containing billions of cells will block convection and reflect heat energy back to its soin-ce. Excellent thermal insulating properties make such composite foams very usefiil in civil construction as well as in refractory applications. 

The incorporation of foreign ions into the crystal lattice of the mullite for refractory applications has been examined in depth. These investigations established the content of ions of a specific size that can be incorporated into the mullite lattice without destroying it. 

Thorium oxide ThO has the highest melhng point (3300°C) of all the binary oxides and has found some uses in special refractory applications. 

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