Research Of Mixing Flow Field In Flue Gas Desulfurization Tower Of Coal-fired Power Plant

At this stage mixing devices in desulphurization plant are side entering agitator, limited by the working conditions the side into mixing devices has some shortcomings. Now a kind of rotary jet mixing device with the self-excited pulsed nozzle will be used in the desulfurization tower. This paper establish the numerical model of side entering agitator and rotary jet mixer in order to compare the mixing consequent.Firstly, according to the working conditions, the side entering agitator and rotary jet mixer installation parameters, and the structure size of the non-self-excited pulsed nozzle and self-excited pulsed nozzle are determined. Models of the flow field are established which are used for meshing and to identify boundary conditions and numerical methods for numerical simulation.Secondly, this paper analyzes the results of numerical simulation of the flow field, that includes the velocity distribution curves of different planes at different positions, the attenuation and distribution of jet in order to study of the jet mixing effect on the fluid in tank. Analysis of the air volume fraction distribution of oxidation air of horizontal and vertical plane is used to investigate the effect of the rotary jet mixing device diffusing the oxidation air. Analysis of the velocity and distribution of gas volume fraction in the same location and plane of two mixers is used to compare the results of mixing.Finally, the models of non-self-excited pulsed nozzle and self-excited pulsed nozzle of rotating jet mixer are established for flow field numerical simulation. According to the analysis of pressure distribution and velocity distribution in two nozzles, the periodic variation of pressure, speed and vapor concentration exists in self-excited pulsed nozzle, the central axis velocity of two nozzle is compared to determine the changes of jet combat power.