CelSian Glass has developed a fast and flexible Energy Balance Model (EBM) for complete glass melting furnaces. EBM is able to model energy balances for all furnace parts such as the melting tank, the combustion space, working ends, regenerators, recuperators and batch pre-heaters. EBM determines all heat flows and other interactions between these different furnace parts. It is equipped with an extensive database of batch, glass and refractory material properties. With this integrated furnace model, the overall energy balance as well as combustion, regeneration/recuperator and furnace efficiencies are determined. The total energy consumption in MJ/ton is determined, as well as structural losses and cooling losses. Crown and bottom temperature profiles are generated and flue gas and throat temperatures are reported. Thus, EBM enables the determination of the potential energy and CO2 emission savings from which recommendations on modifications of process settings can be deduced and/or furnace designs can be optimised. The paper will show results of a validation study for a TV-glass furnace, for which detailed measurements are available. The same furnace has been used within the TC21 to validate several computational fluid dynamics (CFD) models against the measurements. Next, results of complete furnace simulations by means of EBM are presented, showing the effects on energy consumption of changing parameters such as cullet fraction, amount of gas, boosting heat, air excess, raw material composition, refractory insulation and cold air leakage. The impact of changes in these parameters will be discussed. The potential energy savings due to improvements as compared to the original design will demonstrate the applicability of EBM for optimising the energy and CO2 performance of glass melting furnaces.
