Reconstruction And Capability Test Of Multilevel And Multiscale Fgd Liquid-column Tower

Slurry jet FGD is one of the most advanced FGD technologies, which is characterized by strong interaction between flue gas and liquid, stable and reliable operation and high-efficiency desulfurization. In the thesis, a new style multilevel slurry jet FGD is proposed by optimizing spray nozzles. Several tasks are carried out including the study of character of liquid-column atomization, simulation of flow field and test of desulfurization capability. Diameter and velocity distribution of atomized slurry droplets have great effect on desulfurization. The distribution rule of droplet diameter is obtained by traces test and Reynolds time–averaged Navier-Stokes equations about fan-shaped spray nozzle and pressure rotating spray nozzle.The computational fluid dynamics(CFD) is used to simulate the distribution of the flow field in new style of multilevel and multiscale liquid-column tower with the two style nozzles. It can be predicted that different nozzles could affect the distribution of the gas flow field with Lagrange discrete phase model based on Rosin-Rammler equations. Numerical simulation and experiment results showed that the spray slurry has obviously integration effect on the flue gas with combination of pressure-swirl-atomizer and flat fan atomizer nozzle, they could prevent gas collision and avoid entrainment. The optimized value of inlet velocity of flue gas and slurry mass are 20m/s and 2.88m3/h respectively. Droplet break-up shows two mechanisms : tip pinch-off and neck pinch-off.The desulfurization efficiency decreased with the increasing of flue-gas velocity, pH of absorbent and inlet concentration of SO2, however, it increased with the increasing of the liquid-gas ratio. The desulfurization efficiency reached to 97% under the conditions of liquid-gas ratio and inlet concentration of SO2 were 1.5L/m3 and 470 mg/m3 respectively. The simulated results agreed well with the test results. The results may give some directions on the further study of the new style multilevel and multiscale FGD.