METHOD OF PRODUCING HEAT INSULATION MATERIAL Russian patent published in 2011 - IPC C04B38/02 

FIELD: process engineering.

SUBSTANCE: invention relates to production of heat insulation materials. Proposed method comprises metering silicon-containing material and alkali, their mixing and curing for 2-24 hours, thermal treatment of produced mix and grinding it to grain size smaller than 0.5 mm. It comprises also mixing said mix with has-forming agent. Metallurgical scoria makes said silicon-containing material. Blue john is added to the mix of metallurgical scoria and alkali prior to their thermal treatment. Note here that aforesaid components feature the following ratio, in wt %, i.e. metallurgical scoria - 70-85, alkali - 10-20, and blue john - 5-10.

EFFECT: higher hardness.