OCR Text |
Show 6 data of conventional technology. The NOx emission in FDI combustion gives far lower value than FOR, such as 1/10 of the case of no NOx reduction method. 1000 r-----~----~----~----,-----~2100 E 800 0. 0. .~0. - 600 ..- liN Q. )( 400 0 Z 200 , , , Inpu~ 230 kW" Air ratio ,1.1 : ·······-···-~-·-···-·-··-··t·--·············l······--···?··o·_· ~'~~~--~~_~1.~-i __ 1680 E 0. 0. 'C) 1260 ~ II N Q. 840 )( o z 420 o ~----~----~----~----~--~ 0 500 700 900 1100 1300 1500 Furnace Temperture ·C Fig.6 NOx Characteristics (the effect ofFDI and FGR) 3.3 EFFECT OF PROCESS PARAMETERS ON NOx EMISSION The experiments were done with changing the parameters those decide the FDI combustion characteristics, such as below: 1.Injection velocity of air and gas. 2.Location of gas nozzle (distance between gas nozzles) 3.Angle of gas nozzle. Fig.7, Fig.8, Fig.9 show the influence of the air velocity, the gas nozzle location, and the gas nozzle angle. Also, Fig. 1 0 shows the flame length of the different cases. The NOx emission level becomes lower, when the air velocity is higher, the distance between gas and air injection ports is farther, and the injection flows of gas and air are closer to parallel. As the FDI combustion makes generally long flame, a suitable design including the burner arrangement so as to produce the appropriate flame length, is required in case of the applications to the actual furnaces. |