OCR Text |
Show Heating pattern ^ri2r^y~o~^y~o^r&^ Fig.6 High quality heating process using regenerative burners with high frequency alternating operation. New heating process In order to achieve high thermal efficiency as well as low nitric oxide emission, the combination of a pair of regenerative burners and the high rate of recycling of burned gas in the furnace has been adopted in a high performance industrial furnace run by highly preheated air. Accordingly, the features of the technology, not only the high frequency alternating flow operation of a pair of burners but also the distributed combustion in low oxygen circumstances, contribute to produce a uniform temperature distribution in the furnace. Practically, a uniform temperature distribution across the process is produced in the case where a lot of pair burners are installed along a heating process as shown in Fig.6. Although the existence of local high temperature in the process, which is often seen in typical heating processes like in Fig.7, may cause the damage or nonuniform heating of materials, the cross sectional uniform heating performed in the n ew process allows higher average furnace temperature as a result of eliminating the local over-heating, hence the higher thermal efficiency of the process as well as the high quality of products due to uniform thermal treatment |