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Show A number of reburn demonstrations have been pioneered in Europe and the U S A , especially for large, utility boilers. B G Technology was a leading partner in the demonstration of gas reburning on a 600 M W e coal-fired boiler at the ScottishPower Longannet power station, which achieved a 5 0 % N O x reduction without any adverse effects on the boiler's operation or availability. In for example the glass industry, Pilkington have developed their so-called "3R" Process in which the reburn gas is injected at the top of the exhaust regenerator. The regenerators associated with the furnace now also act as "reactors" as well as a heat recovery device. The resultant emissions from glass furnaces where "3R" has been applied have resulted in significant N O x reductions, below the limits set by T A Luft (500mg/Nm3 at 8 % 02). Another low-NOx option for glass melting is the Oxygen Enriched Air Staging (OEAS) process developed by IGT and marketed by Combustion Tec in the U S A . O E A S has been shown to give up to 7 0 % N O x reductions in commercial operation. Advances in Catalytic Combustion Catalytic combustion is a technology, which has been popular in the USA for many years, but in the U K has only lately become established for drying and baking processes: Figure 8. A number of high profile demonstrations have shown considerable savings in production times or energy costs or both, when compared with traditional convective or electric infrared oven systems. The applications cover a very wide range of industrial activities, including metals component manufacture, wood and plastic products. The low temperatures associated with these catalytic heaters make them particularly attractive for finished products which require drying of solvents, curing of paints & laquers and fixing solvent-based glues. In vehicle production, Ford U K is now using catalytic heaters in their paint shop, replacing electric infrared heaters, and has achieved an energy saving of 8 0 % along with a much higher level of product finish. In addition, Ford has seen safety benefits in the fact that the gas-fired heaters minimises the hazardous period created as the paint solvents flash-off. Likewise, in the production of laquered external wooden doors, the Manse l,,m Wtit' K1r\h v rtvn ( .il.ttyM tit*) /Vrt«*.i» ftommtftj /oM//,if*wi Kid (..i\ hght Pjo Figure 8 : Schematic diagram of a catalytic heater |