Raw materials trends in refractories

• Autores: Ted Dickson, Industrial Minerals
• Localización: Industrial Minerals, ISSN 0019-8544, Nº. 564, 2014 (Ejemplar dedicado a: Septiembre)
• Idioma: inglés
• Texto completo no disponible (Saber más ...)
• Resumen

  • Refractories companies and consumers of refractories, most notably the steel industry, but also cement and lime, glass, non-ferrous metals, ceramics and various other industries where elevated heat is required, do not like to change tried and tested formulations. The consequences of premature refractory failure are far greater than just the cost of relining the vessel. Loss of production from increased downtime, as well as potentially dangerous breakouts from failure of refractories, are of even greater importance. Because consumers are risk averse, they tend not to change refractories suppliers easily, nor do they readily accept reformulation of refractory products. If they do, they are always looking for either lower cost or improved operating performance, preferably both, although lower cost does not necessarily mean lower priced refractories but lower total cost for the lifespan of the product.

    Over many years China has had a major influence on the supply, and more recently, the demand for refractory raw materials. It is well known as a major producer and exporter of magnesia, refractory bauxite, brown fused alumina, flint clay, silicon carbide and graphite. It also has some production and intermittent exports of white fused alumina and has become a significant producer of tabular alumina as well as dolomite based refractories. There are also considerable amounts of refractory clays produced, mainly for local consumption, as well as some relatively recent development of andalusite production.

    The chart below shows rough estimates of consumption of some of the main refractory raw materials. It is difficult to reconcile the amount of raw material used with refractory consumption as the total represented in the chart only comes to about 35m tonnes, whereas total consumption of refractories is currently estimated to be over 40m tonnes. However, the chart excludes material used as binders (with the exception of CAC), insulating refractories such as ceramic fibres, and some specialty refractory materials. An estimate is included for recycled refractories, which tend to be limited to non-critical applications, but this is a growing trend. At least part of the discrepancy will likely come from incomplete figures for both refractories and raw materials in the domestic Chinese market, which represents more than half of all refractories consumption, as high as 65% by some estimates.