Optimize On Inlet Structure For Canopy Wet Desulfurization And Dusting Tower By Numerical Simulation

The total suspended particulate(TSP) and sulfur dioxide are still the primary air pollutant of China in present period,and environment protection operators have done a lot of study to reduce and control the air pollutant. Some industrialized technologies of flue gas dedusting and desulfurization are reviewed and analyzed,and the principles and characteristic of the technologies of dust-collecting and desulfurizing.On the basis of systematically summarizing predecessors’ work ,Professor Li Caiting designed the new towers for wet dedusting and desulfurization,which were the tower with umbrella sloping plates. With the high efficiency of dust removing , simplec and compact configuration , and low operating cost , the equipments has wide application in the future.In the paper,the gas- solid two-phase flow in the new type of tower was numerically simulated by using of CFD (computational fluid dynamics) software.The k-εturbulence model,Discrete Phase Model(DPM) were used to simulate the 3-D gas- solid two-phase flow in the new types of wet dedusting and desulphurization tower with umbrella type plates by using FLUENT package,SIMPLEC algorithm was used in simulation,The existing problems of asymmetric flow-fields at the inlet of the tower were revealed. In order to adjust the flow-fields and improve the efficiency of desulfuration and dedusting, fixing the straight rectifying plates, stepped shape plates or curved shape plates at the inlet is presented on the basis of the numerical simulation. The distribution of the velocity in the section on the y=0 and fly-ash concentration, velocity and pressure in the section on the z=0.21 m were analyzed. Simulation results show that:The flow fields in the tower can be adjusted to an ideal state by fixing the stepped shape plates and curved shape plates, so that the dust gas can be purified with high efficiency.Adopting the k-εmodel and the SIMPLEC algorithm, the 3-D gas- solid two-phase flow field in the new types of wet dedusting and desulphurization tower with umbrella type plates is simulated with software of FLUENT. The influence of different tilted ways and inlet angles of flue gas on the flow field in the new type of tower is analyzed. Simulation results show that:Upward inclined entrance effectively increased flue gas volume at the bottom of the inlet, so that the dust gas can be purified with high efficiency. However, downward inclined entrance can make gas distribute more even in the tower. The results present better agreement with empirical date.Finally,the simulation results are of major significance for the optimization design and practical operation of the tower. Using CFD simulation method can shorten device developed time and reduce experiment and design cost, which possesses a very good economic benefit.