Granules production

Glass powder storage silos
After grinding, the glass powder is stored in silos, from which portions weighed accurately, according to the recipe are automatically fed into the mixer that mixes them with a foaming agent, and then moves the glass powder mixture into the furnace feeders.

Charging the glass powder mixture into the furnaces
From the glass powder fed in, the two 45,000 m3/year capacity hybrid tunnel furnaces produce the foam glass granules in about 30 minutes. By hybrid furnace, we mean the effective combination of natural gas and electric heating elements: 70-80% of total furnace consumption is generated in the front section, where the glass is heated from 30 ˚C to 800-900 ˚C, followed by heat soaking at 900˚ C. As heating up requires continuous heating, and therefore continuous heater operation – compared to heat soaking, this is the most energy intensive stage of the entire process –, in the front third section gas burners are used, a suitable choice from an operational, product quality and cost perspective. Glass is more sensitive during heat soaking at high temperature, therefore we do it with more easily controllable electric heating elements, which, in contrast to gas heaters, can be switched on and off for tenths of a second to ensure better heat distribution, and in this way high product quality is better ensured.

Hybrid furnaces

Foam glass granules: the end-product