HYBRID Technology – Advance for Sol-Gel Bonded Refractory Concrete

J. Neese, B. Kesselheim, S. Rollmann, S. Scheffer

Refratechnik Steel GmbH, 40549 Düsseldorf/Germany


Volume 11, Issue 4, Pages 37 - 43


Monolithic refractory castables can contain different bonding agents. The commonly used cement and silica sol binders have different advantages for their usage. The cement bonding with calcium aluminate cement is characterised by the development of high strength at a temperature up to 1000 °C. A general disadvantage is, that corresponding linings need to be heated up very sensitive, especially at the initial heat­up. Because of the containing calcium oxide there’s also a risk of formation of low melting phases.A further alternative is the cement free silica sol bonding. It is proven, that the heating up properties aren’t critical and there is no risk of the formation of low melting phases, cause of missing CaO. The probably only drawback of this system is the mechanical strength at temperatures up to 1000 °C, which can lead to a higher risk of damages of unshaped and prefabricated components. Due to several weaknesses of these commonly used binders, the aim of this project was to invent an innovative bonding system with improved properties.The focus was on high strength development over the complete temperature range, fast heating up properties and a good temperature durability. This novel HYBRID bonding system is directly compared to the both conventional used systems (CAC/silica sol). Furthermore, there should be given an overview of possible applications including outlook to further developments.


HYBRID, silica sol, green strength, fast heating-­up


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