Development History of Refractory Materials

More than 4000 years ago, China used clay with less impurities to burn pottery, and has been able to cast bronze. In the Eastern Han Dynasty (25-220 AD), clay refractory materials were used as kiln materials and saggers for firing porcelain. At the beginning of the 20th century, refractories developed towards high-purity, high-density and ultra-high temperature products, and developed amorphous refractories and high refractory fibers (used for industrial kilns above 1600 ℃) that do not require firing and have low energy consumption. The former, such as alumina refractory concrete, is commonly used in the inner wall of the secondary reformer of the synthetic ammonia production plant in large chemical plants, with good results. Since the 1950s, the rapid development of atomic energy technology, space technology, new energy development technology, etc. requires the use of special refractory materials with comprehensive excellent performance, such as high temperature resistance, corrosion resistance, heat shock resistance, erosion resistance, such as oxides with a melting point higher than 2000 ℃, refractory compounds and high-temperature composite refractories.

Refractories in ancient times, the Middle Ages and the Renaissance, refractories for blast furnaces, coke ovens and hot stoves before and after the Industrial Revolution, new refractories and their manufacturing processes in late modern times, modern refractory manufacturing technologies and major technological advances, and prospects for the development of refractories in the future. Refractories and high-temperature technologies came together, roughly originating in the middle of the Bronze Age. Clay refractory materials have been used as kiln materials and saggers for firing porcelain in the Eastern Han Dynasty. At the beginning of the 20th century, refractories developed towards high purity, high density and ultra-high temperature products, and at the same time, unshaped refractories and refractory fibers with no firing and low energy consumption appeared. Nowadays, with the development of atomic energy technology, space technology and new energy technology, refractories with high temperature resistance, corrosion resistance, thermal vibration resistance, erosion resistance and other comprehensive excellent properties have been applied. There are many factories producing refractory products in China. China has rich resources, and it is precisely for this reason that major foreign investors also come to China to show their skills. In the northeast of China, there are a lot of refractory suppliers, which led other foreign investors to question the low export price. In 2003, the EU proposed anti-dumping against new Chinese refractory products, which restricted the export of products to the EU. In 2006, in order to protect the massive loss of raw material resources, China reduced or exempted export tax rebates for some industries, thereby greatly limiting the export of products. However, this does not limit the sales of some foreign brands to a large extent, because they have decades or even hundreds of years of sales and production experience, have greatly occupied the market, and have created their brand effects on all continents.

1. Improve the level of comprehensive utilization of resources and guarantee capacity.

By 2015, high-end refractories will be basically self-sufficient. The comprehensive utilization rate of magnesite ore resources will not be less than 90%, and the comprehensive utilization rate of refractory clay ore resources will not be less than 80%. By 2020, the comprehensive utilization rate of the two mineral resources will be higher than 95% and 90% respectively.

2. We will step up efforts to conserve energy and reduce emissions.

By 2015, the energy efficiency level of major energy consuming equipment will reach Grade I, the comprehensive energy consumption of major products will be reduced by more than 20% compared with 2010, the total emissions of sulfur dioxide and nitrogen oxides will be reduced by more than 8% and 10% respectively compared with 2010, and the recovery and reuse rate of used refractory materials will not be less than 50%. By 2020, the recycling rate of used refractory materials will be higher than 75%.

3. Improve industrial concentration.

By 2015, 2-3 enterprises with international competitiveness will be formed, and several new industrial demonstration bases will be established. The industrial concentration of the top 10 enterprises will reach 25%. By 2020, the industrial concentration of the top 10 enterprises will increase to 45%.

The workability of refractory materials includes consistency, slump, fluidity, plasticity, cohesiveness, resilience, condensation, hardening, etc.