Study On Experiment And CFD Simulation Of The New Structured Packings

In view of the advantages and disadvantages of the porous foam packings.We composited Fe-Gr-Ni foam packing and foam Al packing into a new structured packing and carried out the hydrodynamics and mass transfer experiments with air-water system and cyclohexane n-heptane system in this paper.The experimental results shows that the new type of composite packing reduceds the pressure drop by about 70% compared with Al &CY composite packing under the same condition,which is close to the CY wire packing.It has a higher flooding point gas velocity,flexible range of operation,and large liquid holding capacity.The number of theoretical plates is up to 5.This shows that the new type of composite structured packing is an excellent novel packing,it combines the advantages of Fe-Gr-Ni foam packing and aluminum foam packing and its separation efficiency is between Al & CY composite packing and CY wire packing.Moreover,In order to further study the gas-liquid mass transfer mechanism of the composite structured packing,cube model for foam aluminum structured packing and the tetrahedron model for Fe-Gr-Ni foam structured packing were established for computer simulation.The simulation results agree well with the expremental results.This result predicts that the models are reliable.Then an other 3D CFD simulation study was carried out on the composite packing on this basis.The simulation result shows the gas-liquid contact in the channel is mainly concentrated in the Foam Al part while the Foam Fe-GR-Ni part leading the flow to reduce the pressure drop and the gas-liquid contact in it was mainly happened at the joints.What's more,the flow and mass transfer efficiency in the porous foam structured packing are mainly influenced by the gas-liquid velocity,channel and pore size.Under the experimental conditions,when the pore diameter of foam Al is 1.23-1.27 mm,the skeleton diameter of the foam Fe-Gr-Ni packing is 0.75~1.25 mm,the diameter of foam Fe-Gr-Ni is larger than 2mm.When the gas velocity is 0.005-0.05m/s and the liquid velocity is 0.001-0.01m/s,the gas-liquid distribution in the composite is better,and it is good for heat and mass transfer.These simulation results can provide theoretical guidance for the improvement of the foam structured packing in the future.