The melting furnace is typically a non-flexible system as the higher efficiency in terms of consumption can be achieved at maximum load. The electric booster is a smart option used to increase furnace pull and to enhance the furnace flexibility keeping the melting tank size compact.
The pull increase is proportional to the energy introduced in the glass. By experience the contribute of booster to the melting capacity of a given tank is approx. 40 kg/day of additional molten glass per each kW of electricity installed. This data is generally accepted but can vary in function of booster design, position of electrodes, type of control, characteristics of glass, etc..
One of the advantages of boosting system is the possibility to reduce the superstructure temperature thus reducing the fuel consumption and, also, extending the life of refractory structure keeping the same pull.
Our boosting systems are designed to be perfectly integrated with the furnace design and the main heating system and take into account all the critical parameters of the process. We propose different kinds of boosting systems:
- Melting type (or distributed)
- Barrier type
- Throat booste
These two systems can operate separately. But whenever there is the need to achieve the best performance, a combination of both can also be provided.
The melting booster is installed between the dog house area and the tank hot spot. This booster is used to distribute the heating energy to the glass homogeneously. The position of each single electrode is determined by our designers in order to improve the pull under any condition. In small and medium size furnaces the booster system is normally single zone. In case of larger tanks or when there are technological requirements the booster is split into two separate zone. This combination allows the operator to find more easily the suitable setup to optimize pull and reduce fossil energy consumption.
The barrier booster is installed in the furnace hot spot and is used to create convective currents in the glass which enhance the glass circulation from the bottom to the surface. As result the average resident time of the glass increases and the refining process is enhanced. This booster is extremely efficient and used in many applications as alternative solution to the melting booster. When the maximum tank performances are wanted a combination of both boosters is used.
Throat booster is used when the geometrical characteristics of the throat require the external heating at furnace filling and start-up. This system prevents the glass blockage and is extremely useful in case of tanks for colored glass production during the operations of emptying and filling.
The booster package provided by FALORNI TECH includes the complete engineering of the system as well as the detailed design of the refractory assembly.
Whenever required a mathematical modeling of the system is carried out in order to determine the exact position of electrodes, the transformer characteristics, the voltage and current range in function of glass resistivity and tank geometry.