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Show Recuperative Burners:- Initial work on air preheat systems focused on the development of recuperators and particularly recuperative burners. The development of the recuperative burner: Figure 2, resulted in a single compact unit which combined the functions of the burner, flue and recuperator. This overcame the disadvantages of conventional recuperators which are often large and need to duct hot gases around the system. (In certain cases separated recuperators are still the best option.) The new burners, size range 60 to 900kW, are easy to install and offer potential cost reductions, particularly as they often replace multi-burner operations. The take-up of recuperative burner technology (both BG Technology's design and other manufacturers) has been considerable. Typical air preheat temperatures are around 600°C and this gives energy savings of 3 0 % . Likewise other operational advantages are seen in terms of quicker light-up times and improved product quality resulting from lower soaking times for the hot stock combustion products Figure 2 : Schematic of Recuperative Burner Compact Regenerative Burners:- Regenerative systems have been around for many years but their application tended to be restricted to large furnaces, such as glass melting furnaces and steel reheating furnaces. The main reasons for this was the high capital costs, complexity of operation and the need to operate the units on a continuous basis. B G Technology, working with Dyson-Hotwork, undertook a project to design a new regenerator system, aimed more specifically at smaller applications including batch operation. Developments in materials and burner controls were utilised to develop a novel compact system as illustrated in Figure 3. The regenerative burner consists of two cylindrical towers filled with alumina balls, which in turn either act either as a heat sink for the exiting combustion products or preheat the incoming air. The switch over from one tower to another can be very short, down to a matter of minutes. The final production regenerative burner units exhibited very high effectiveness (-90%), high furnace efficiencies (65% fuel savings) and field trials indicated the system to be robust and reliable. Regenerative burners are n o w in regular use in the iron and steel industry as well as other industrial markets such as glass manufacture |