What types of regenerative glass melting furnaces does IWG Glasofenbau supply?

A recuperative end-fired glass furnace is a gas-fired melting furnace with burners at one or both ends. The combustion air is preheated in a recuperator: hot exhaust gases transfer their heat to the supply air. This reduces gas consumption, ensures stable flame ignition, and increases efficiency.

The end-firing creates a clear heat axis from the burner to the refining zone. This supports refining, ensures high homogeneity, and maintains uniform temperatures across the glass surface, breast walls, and crown. Crucial factors are well-controlled flame length, burner pressure, and draft control. A slightly lean operation can reduce NOx emissions; with a moderate excess of air, reduction effects in the glass remain minimal.

Where limits are strict, low-NOx burners, flue gas recirculation, or moderate O₂ enrichment are available as equipment options. The result is a robust, energy-efficient furnace solution for small to medium pull rates – with reliable product quality, a compact design, and an attractive investment.

With the recuperative end-fired glass melting furnace from IWG, you can produce the following types of glass, for example:

The regenerative side-fired glass melting furnace uses rows of burners arranged on the sides to achieve very uniform energy input across the entire width of the furnace. The flames, directed transversely to the melting direction, create pronounced cross-mixing and ensure stable temperature profiles from the inlet to the refining and working zones.

This allows critical areas such as the glass surface, breast walls, and crown to be operated with very high thermal homogeneity – a key factor for high glass purity, low bubble and striae formation, and reliable color settings. The design of burner spacing, flame length, burner pressure, and draft control between the regenerator blocks is precisely tailored to your raw materials, glass type, and pull rate.

Thanks to regenerative air preheating, the side-fired furnace operates with very high thermal efficiency and significantly reduces specific energy consumption. Through suitable low-NOx burners, staged combustion, flue gas recirculation, or moderate O₂ enrichment, even demanding emission limits can be reliably met – while maintaining high melting performance and glass quality. This design shows its advantages particularly in the medium to high pull rate range: uniform temperature distribution across the entire furnace width, stable, low-disruption operation, high plant availability, and an overall compact furnace geometry.

Our regenerative furnaces are always tailored to your specific application. Geometry, furnace size, pull rate, as well as the division of the charging, melting, refining, and working areas are variable. The system is adapted to your raw materials, glass type, and the desired temperature profile through burner arrangement, flame guidance, regenerator size, and materials.

Furthermore, the internal hydraulics can be influenced very specifically: A thermal barrier stabilizes the heat balance at the transition to the refining zone, smooths out temperature peaks, and supports bubble separation. The electric throat heating acts deep within the bath, keeps the viscosity in the required range, and ensures reproducible temperature profiles right up to the outlet.

In addition, bubbling systems – tailored to your recipe – are used, which can be operated with either compressed air or oxygen. The finely dosed gas promotes convection, accelerates refining, and reduces striae and inclusion defects without altering the glass chemistry. We adjust the proportion of melting and refining through the design of barriers and throats: geometry, position, and flow are selected so that heat is introduced into the bath in a targeted manner and the flow forms the desired circulation patterns. Optionally integrated air or furnace cooling creates additional control reserves at critical points.