Study Of Gas Distribution Performance On The SiC Foam Tray

SiC foam material has been applied as monolithic tray for distillation column in our previous study. The tray has excellent characteristics both in hydrodynamic performance and mass transfer efficiency, but there is one disadvantage that the gas distributon is uneven when the F-factor is small. Therefore, a systematic understanding of the gas distribution process on the foam tray should help to the design of commercial application.In this article, local gas hold up distribution and bubble size distribution are used to measure the gas distribution. The local gas hold up is tested by the conductive probe and the number of test point is counted in different local gas hold up. The bubbles are captured by the high speed camera to measure the bubble size. Furthermore, a three stage process model is put forward to explain the uneven distribution of gas phase. The results show that the surface structure and the pressure drop of SiC foam is the decisive factor for the gas distribution performance.For industrial application, a new SiC foam valve tray was developed depending on the understanding of the gas distribution process on the SiC foam. Compared with the previous SiC foam valve tray, the new tray had better gas distribution performance and new fixed function, which leaded the installation easier and more suitable for industrial application. In order to verify the hydrodynamic performance of new tray, fluid mechanics performance test of the new tray was made, the pressure drop, entrainment, clear liquid height and weeping was tested at normal temperatures and pressures in the tower with 600 mm diameter. Compared with the F1 float valve tray, the new SiC foam valve tray had lower dry pressure drop because of its higher opening ratio; and the new tray did not weep even at small F- factor due to the porous structure of foam SiC. However, the new SiC foam valve tray had higher wet pressure drop compared with F1 float valve tray. In general, the new SiC foam valve tray had good hydrodynamic performance and broad market prospect.