Welcome to the Glass Age

116 Hybrid melting Hybrid melting entered the glass dictionary in 2017 being mentioned by companies such as Glass Service & FIC-UK, Fives, TECO, Horn and Sorg. Previously discussion was limited, though hybrid melting simply means more than one heat source and has a long history. It is analogous to hybrid cars where the engine is the main power source, while the battery-driven electric motors can move the car short distances and add extra power during acceleration. Previously, electric boosting in glass production was often for 15-30% of the total energy input. Combustion is also used in hybrid melters (H 2 EM) but 50% or more energy comes from electric heating. The thermal efficiency of the electricity is 85-90%, while combustion is about 50%. A smaller all-electric furnace (<4 TPD/m 2 ) has the following advantages: • No emissions (NO x , SO x ) or particulate dust, so no filter or cleaning costs for waste gas. • No chimney stack and therefore fewer complaints from neighbors. • Lower investment: no crown, regenerator or flue gas channels. • No regenerators to clean. • Lower raw materials costs, because volatilization reduced. • Lower repair costs and shorter repair times. • Efficiency is less impacted by furnace size and capacity. Hybrid melting restores the following advantages relative to electric melting: • Pull flexibility. • Reasonable furnace lifetime (10-12 years). • Experience of operators (behaves more like a standard furnace). • Less dependent on electrical power availability (net stability). Switch to more combustion. • Cullet can be up to 90% of batch. • Unchanged furnace size and aspect ratio, to match existing hall. The ‘Furnace for the Future’ (F4F) project organized by a consortium of glass makers [11] is expected to adopt Figure 7.6. 3D view of the combustion space and glass melt in a Horizontal Hybrid Electric Melter at 80% electric mode and 20% firing mode. Source: Courtesy of Glass Service a.s. (www.gsl.cz ) and FIC UK (www.fic-uk.com) .