| Liquid column impact tower is a new kind of wet desulphurization technology. Porous baffle is added on the basis of liquid column empty tower for reconstruction. It has the advantages of fluid column empty tower and porous plate absorption tower, and is one kind of ideal desulphurization installations. Fluid column impact tower has the characteristics of high desulphurization efficiency, reliable performance, strong adaptability, high level of automatic control in technical process, low initial investment and running costs and so on. It is greatly suitable for flue gas desulfurization in industrial boiler. At present, the study on liquid column impact tower is just starting, and it still keeps experimental research in the lab scale. Therefore, it has a great significance to study the large-scale fluid column impact tower for industrial application.Based on the platform of business software FLUENT, flue gas entrance angle, baffle structure, wind speed in the tower were simulated and optimized to achieve good gas-liquid mixing effect. This work will provide theoretical basis for the design of large-scale fluid column impact tower.The characteristics of gas-liquid flow were simulated by using Euler-Lagrange method, and it took fluid column impact tower as the physical model. The impacts of the structure and operating parameters of fluid column impact tower to the gas-liquid flow field were studied. The best structure and operation parameters for fluid column shock tower were concluded, which provided the design basis for the construction of the experiment rig. The test running structure of the experiment rig showed that system had high desulfurization efficiency, good gas-liquid mixing effect, please see "Bases for industrial waste fluid column tower wet desulphurization experiment research" paper for detail. Results showed that:the entrance angle had significant influence on the tower flow. When the entrance was 15°, the flow field in the tower and velocity distribution were the best; Porous baffle had significant rectification effect on airflow. When the porosity factor was 0.5, the influence was the best by synthesizing factors like the rectification impact of porous baffle on the flow field, flow velocity in the tower and so on. The best airflow velocity for the tower was 3m/s.Selecting a wet desulphurization absorption tower in 220 t/h boilers in a chemical plant as the physical model for numerical calculation, this paper did numerical calculation on gas-liquid two phase flow characteristics inside the tower with Euler-Lagrange method, studying the flow and pressure distribution, which provided theoretical basis for optimization of structural and operation parameters of the desulphurization tower and large-scale design of impingement towers in chemical plants. The research results showed that:slurry spray effected significantly on rectification performance inside the tower with uniform air distribution. Reflux occurred at the region of the porous baffle, strengthening the mixing between gas and liquid, and prolonging the residence time of the air flow in tower. The height between the porous baffle and the slurry liquid surface exerted significant influence on the gas-liquid two phase distribution inside the impinge tower; when the height was 1.56 times of the equivalent diameter of tower, the gas-liquid two phase distribution in the tower was more uniform, which made better performance. With the height increasing, the pressure tended to be uniform and showed a lamella distribution at the same height level in the turbulent region between the tower entrance and the porous baffle, while the air pressure showed no significant changes in the region between the porous baffle and the tower exit. |
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