| Compared to other methods, spray drying FGD(Flue Gas Desulphurization) technology is wider application for its low occupying space, no erode and good removal effect,but as its technical support for the spray drying purification mechanism is relatively backward. Spray drying process is a very complex of flows, heat and mass transfer and chemical reaction. Although there are a lot of research in this area, because of many aspects of mechanism have not been awared and understood very well. This hindered the further application of the technology and development, so the further study of spray drying tower gas-liquid two-phase flow and heat and mass transfer dynamic characteristics is very necessary.And then, in this paper, on the basis of the status quo in-depth analysis of spray drying FGD technology, optimal design the purification devices of spray drying in flue gas flow rate of 580 Nm3/h. At the same time, establish a spray pattern different from the traditional physical model of reverse spray. Gas phase was being described by using RNG/κ-εturbulence model, and the particle phase was being described by the orbit model.The use of computational fluid dynamics methods analysis the internal flow field in SDA(Spray Drying Absorber) by using Euler~Lagrange simulate gas-liquid two-phase flow .And mainly inspected the jet different locations, different injection pressure and flow of imports under different flue gas desulphurization tower of smoke flow and movement of atomized slurry drops, evaporation, as well as the drop with the high temperature plasma atomization gas between the Heat and Mass Transfer Dynamic characteristics of the changes and reach the following meaningful results:①In terms of the gas phase without injection,the results indicate that there was a significant asymmetry of opposite inlet side of the inlet velocity greater than the velocity side without the flow equalization board, moreover there exist a big return to the side on air inlet; the flow field is more uniform after adding the flow equalization board, and it showed symmetrical basically and no adherent phenomenon.②Versus increasing flow equalization board in SDA under reverse injection comparied of the gas phase filed without injection. Since the initial speed difference is great between slurry and gas,the slurry play a obviously disturbed effect for flue gas flow on the tower.③The injection height is an important factor effecting the flow characteristics of SDA. Injection too high or too low will cause uneven distribution of flow, lack of disturbance and excessive evaporation rate in the entire tower. Flue gas inlet velocity is the main factor effecting the flow characteristics of SDA, too high velocity will cause contact time is inadequacy, too low will increase operating costs. When too much injection pressure, the slurry will into the equalization board are the Department of the hour jet has a range insufficient, and the contact time is short, these will affect the desulfurization efficiency.④The simulation for the physical model that is running the best parameters for a high injection 2m, injection pressure for 6MPa, imports of flue gas flow rate of 4 m/s.There are better results for enhancing the heat and mass transfer and increasing efficiency desulphurization with such model.⑤In the best operating parameters, the analysis of the different diameter of the particles that its characteristic of displacement and speed changes, the results showed that the diameter is too big that the trip is long and contact time is long with heat smoke. The size is too big that are easy to upthrust the flow equalization board. The size is too small that the speed of evaporation is too quickly.The atomization of the appropriate size of the drop slurry on improving the efficiency of heat transfer and desulfurization is important.⑥The study found that over time increase, SO2 concentration gradually decreased in size, the efficiency of absorption is gradually increasing, and with the increased size, slurry drops to extend the existence of time, the greater the temperature difference between import and export of gas.⑦Inspected 80μm diameter of a single particle slurry drops, around the flue gas temperature along the trajectory of change as the operating parameters of absorbent SO2 absorption of the dynamic changes at the first time, Smoke was found that the temperature increase, with the increase in absorption efficiency, the adsorption efficiency can be achieved around 84 percent.This study lay the theoretical foundation for progress in the field of engineering and technological innovation by using the small and medium-sized spray drying, has very important significance and academic works practical significance.
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