OCR Text |
Show , f e through the The authors have developed a new oxygen/COG combustion reheatIng urnac, d 'ng combined use of steam blowing technology and the divided supply of oxygen or COG, After stu yl app I,I ca bI'l 'I ty to a furnace by several experiments and numerical si,m ulatI' ons, I"t IS re vealed ,t hat furna'ctye height can be reduced to the half of the existing one, while maintaining unifonn reheatmg capacl equivalent to that in conventional furnaces, OXYGEN/COG BURNER WITH STEAM BLOWING First of all, the results of basic investigation for an oxygen/COG burner itself are described. Figure 2 show s schematic view of the experimental furnace used to investigate the feature of oxygen/COO burners. Laboratory scale burners (250Mcal/Hr.) have been tested in the horizontal and cylindrical furnace with inside diameter of 800mm, and length 4OOOmm. The flue gas is exhausted through the hole on the wall opposite to the burner. Longitudinal local temperatures are measured by five thermo-couples placed on l00mm from the inside wall, and local heat flux is obtained from each water temperature difference between inlet and outlet in a water pipe. Each examination was carried out after gas and water temperature steadied. steam oxygen _ COG - 500 water t 4,000 750 750 heat flux' Figure 2 Schematic view of experimantal furnace .st e1am secondary 02 I primary 02 e-- o -s. Figure 3 Schematic view of experimental burner thermo-couple ~ steam ~ COG 7 // primary en ?---- A~ The experimental burner, which gave the best results, is shown in Figure 3, The burner has tw oxygen feeders, and the primary oxygen jet is axially fed from the centre of the burner to maintain tho stable primary flame fonned with COG jet, while the high speed secondary oxygen jet aspirate fl e gas and increases momentum of the flame. Also steam blowing produces high momentum fl s ue well as a long flame resulting from delaying combustion by separating the secondary oxyge an;e as COG, Experimental conditions are shown in Table 1. n rom |