| OCR Text |
Show in Fig. 1, w e have used this pre-heated waste heat recovery technology for energy savings of 174 units of forge furnaces during the past 8 years. Here, w e shall introduce the burner system development of a practical level, relating to energy savings and N O x reduction of forge furnaces which, although small, are numerous. Only natural gas(C12H44,net calorific value is 41.6MJ) is the fuel for the developed burners. 400 350 I 250 150 Rotary type regenerative burner SeH-regenerative burner developed I Low N O x Regenerative burner developed Recuperative burner tor torge furnace developed New shell and tube type recuperator a '93 Year 94 •95 •96 •97 Fig. 1 Track record of forge furnaces using energy saving technology of Osaka G a s Co. 2. Low N O x regenerative burner for forge furnace, the PAX-R burner 2.1 Development concept With the control method and piping flow remaining basically the same, the reducing of the size of regenerative burner systems adopted for large scale hot rolling heating furnaces as they are does not reduce the total cost relative to the burner capacity. Therefore they are difficult to adopt for forge furnaces which are numerous in small scale factories. From such an economic viewpoint and with consideration for the characteristics of forge furnaces, a low N O x regenerative burner, the PAX-R for forge furnaces was developed based on the following concept. © Not only the burner itself but the control system to be simplified ™ No additional control to be made to realize low N Ox - A simple 4-way valve to be developed and used for the changeover valve (D A lower capacity blower and exhaust fan to be used - Burner pressure drop (excluding the regenerator element) to be restrained to a level of 500 Pa Specifications suitable for daily start/stop to be set - Stable combustion and reduction of N O x while the furnace temperature is low to be readily possible @ Installation space to be small and compact |
