The first installation of a Nienburger Glas Batch preheater started in operation in December 1987. After 12 years of continuous operation the furnace will be replaced completely. Some details of the preheater have to be modified during the cold repair, and together with the rebuilt furnace the next campaign for the batch preheater will start long-term experience data heat balances, and energy saving rates will be presented. Two additional batch preheaters were built: one for a cross-fired flint furnace in 1991, and one for an end-fired flint furnace in 1992. Based on experience with these installations, a complete new glass factory for 350 t/day flint container glass was built in 1995 with an integrated improved batch preheater. In 1997, the first preheater for an oxy-fuel furnace with 400 t/day capacity at Gerresheimer Glas was started. The up-to-date practical experience with these second generation batch preheaters, heat balances, and data for NOx emissions are given.
