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Show - 6 - 3. Burner Development The aim of the Steinmuller program sponsored by the BMFT was the development of a pulverized-fuel burner with low NO -TV formation and subsequently the demonstration of the new burner in a 700 MW power station boiler unit. As a 700 MW unit is understandably unsuitable for a burner development program, a prototype of the novel staged mixing burner was optimized in the pilot plant of the International Flame Research Foundation (IFRF). In order to approximate the boundary conditions of the IFRF test furnace (2 x 2 mc£, 6 m long) to actual boiler conditions, water-cooled cooling loops were fitted to the furnace wall to provide a heat sink capable of absorbing approximately 50 % of the furnace heat loading input. The burner size and the nominal burner loading were established according to the usual volumetric heat loading for steam generators (2.3 MW thermal). As similarity cirterion for the difference in scale between a full-size 70 MW burner and the pilot burner (70 : 2.3 MW) a Hybrid model between geometry, residence time and velocity similarity was chosen [5]. 9-6 |