In NTECH’s Industrial Development Center (IDC) a procedure has been developed which can be further upscaled to a full operating industrial plant, as it allows the gelation, solvent exchange and drying step to occur all inside the mould. Handling during the process is thus cost effective.

The Aerogel, porous but solid material which results from the hypercritical drying step, has a near net shape and is withdrawn from the mould to be placed inside the oven where the thermochemical treatment is performed. It is in this stage, inside the furnace with controlled atmosphere, where the ultra-purity is achieved and the silica glass object reaches its final dimensions.

Solvents can be fully recycled and exhaust gases can be easily abated and neutralized. Ethanol is the only byproduct. Due to the relatively low temperatures used in the process, energy consumption is moderate. Final silica glass objects mostly do not need any aftertreatment or machining.