Abstract
The chemical absorption method of post-combustion CO2 capture is widely used in the capture of carbon dioxide processes, which is flue gas post-process. Flue gas composition is complex and has fine size condensation nucleus. After the chemical absorption process, part of the solvent will be adsorbed on the nucleus surface to form aerosols and emission into the atmosphere with the flue gas. Because the size of the aerosol is extremely fine, it does not only cause environmental pollution but if inadvertently inhaled, it will harm the human body. Therefore, as CO2 capture technology matures, aerosol becomes a challenge for the next generation. The common dust removal equipment in the factory includes cyclone dust collectors、bag filters、electrostatic precipitators and wet scrubbers, etc., and only wet scrubbers can remove solid dust and harmful gases simultaneously. Using the most basic water-washed sieve plate tower to solve the problem of industrial aerosol emission will investigate in this paper. However, the experiment of fluid flow behavior in the sieve plates has the high time cost, and there are few studies well discussing this topic. The purpose of this study is to use the CFD (Computational Fluid Dynamics) to establish a model of a sieve plate tower to observe the movement and removal efficiency of the particles. The research was divided into two parts: (1) to build a two-dimensional sieve plate tower, and verify the results of the hydrodynamics behavior, and (2) to investigate the particle motion and removal efficiency in the sieve tray by using the particle tracker. The simulated results of the upstream and downstream liquid velocities on the sieve tray are consistent with the empirical correlation. In addition, the trend of the hydrodynamics in the two-dimensional sieve tray model is correct, the error between the simulated results (including the clear liquid height, froth density, and froth height) and corresponding correlations were less than 22%. For the particle removal simulation, two different turbulent models: standard k-ε and Realizable k-ε were used and compared. The simulated results show that both of the turbulent models can accurately simulate the average air velocity in perforations and froth density. And under the fixed particle size and liquid flow rate, the removal efficiency was improved when raising the air velocity. In summary, the establishment of this model can not only predicted the hydrodynamics and particle direction in the sieve tray but also serve as the reference for factories to deployed sieve plate tower.