| Tiny-oil burner is useful equipment both for diminution oil consumption and increase efficiency of energy and economic efficiency of power plant. The technology of tiny-oil ignition and combustion stabilization is a method that tiny-oil burner is installed in the primary air entrance in order to make the temperature of dense phase pulverized coal rise rapidly and inflame soon by the oil flame. The inflaming dense phase pulverized coal fluid will ignite the dilute phase pulverized coal fluid while mixing with it. By this way the pulverized coal catches fire step by step and the energy of ignition is reduced largely. This technology can satisfy the need in the course of pulverized coal boiler’s startup, stop and low load combustion stabilization.Theoretical analysis and running test combining research method was used in the paper. Firstly the existing research work on boiler ignition device and its application of was introduced. Some basic rules of pulverized coal and oil combustion were discussed and then the main factors that influence on it were analyzed. Both the component and basic principle of tiny-oil burner were also introduced. The feasibility of tiny-oil burner technical reform and its design, system structure and process carried out in a certain power plant were described in detail.Some basic equations used to simulate the combustion process of tiny-oil ignition burner and pulverized coal burner through the FLUENT software were put forwarded in this paper. The standard k-ε equation was used for turbulent flow. Some combustion data of the oil burner including the temperature field and velocity field was obtained, and the effects of the different factors on oil burner and pulverized coal burner combustion were discussed.First, outlet velocity at the atomizing nozzle was obtained through simulating the oil atomization process. The conclusion that fuel flow rate does not affect the outlet velocity at atomizing nozzle can be acquired by used different condition data in the simulation process and comparative analyzed on the obtained results.Secondarily, through the simulation on different combustion condition at oil combustion chamber and comparative analysis on the results, that fuel flow rate will increase the temperature and velocity at oil combustion chamber was found At last, combustion process on different conditions of pulverized coal burner were simulated, and the temperature field was obtained. the influences of oil flow, velocity of primary air, concentration of pulverized coal on combustion were discussed. As fuel flow increasing, ignition of pulverized coal will be faster and temperature will be increased. On the other hand, as primary air speed increasing, ignition of pulverized coal will be slow down, high temperature region will be farther and maximum temperature point be postponed. Meanwhile, as pulverized coal concentration increasing, the ignition of pulverized coal will also be slow down and cause decline in the temperature level and its gradient in the combustion chamber. The theoretical stimulation data and the actual testing data were compared, and the error mainly caused by stimulation and the measure point were discussed. The comparative result shows that the stimulation data is reliable and has a certain reference in application.The capacity calculation and simulation results of tiny-oil burner verified the feasibility on the reform of burner and shows that flame temperature of tiny-oil burner is high, the heat is concentrated, which can satisfy the need of reliable ignition.Although the reform cost of tiny-oil burner is not very high, but the fuel saving rate is high than90%. Therefore, the economic of tiny-oil ignition burner is very high. Due to shortage of energy and its prices high rising at present, tiny-oil ignition burner has greatly important application. This technology can not only meet the needs in the process of the boiler’s start, stop and low load stable combustion, but also has the advantage of energy saving and high economical efficiency. |
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