OCR Text |
Show can be achieved. In the direction of material flow of the new heating process (Fig.6), the temperature in each zone of the process can be controlled independently to produce an appropriate heating pattern in accordance with the temperature change of the heated material. The flexibility of the heating pattern control, being called as free scheduling heating control, brought by the cross-firing of a pair of regenerative burners also contributes to fuel saving and downsizing [17,20]. In contrast, since the burned gas from each burner in the process in Fig.7 forms a bulk flow of flue gas and flows out from the end of the furnace, fine control of temperature in each zone is difficult. Actually, as the result of five years collaboration activity in industries, it is estimated that more than 30 % of energy saving and 20 % of downsizing will be possible in a prototype reheating furnace of 285t/h capacity. If this technology is applied to all of the similar furnaces in Japan, it is reported approximately 5 percent of the national total energy consumption will be saved[20]. Fig.7 Typical heating process with recuperative burners. |