内构件结构对于二级环流反应器流动和传质影响规律研究OA

Installing diamond-shaped internals between the stages of a two-stage internal loop airlift reactor can effectively suppress inter-stage backmixing and enhance gas-liquid two-phase mass transfer.To further improve the mass transfer performance of the two-stage internal loop reactor,this study optimized the structural parameters of the diamond-shaped internals.First,nine diamond-shaped internals with different structural parameters were designed.Then,the bubble flow pattern,gas holdup,and volumetric oxygen mass transfer coefficient in the reactor with different diamond-shaped internals were measured experimentally.Based on the experimental data,the influence of structural parameters on gas holdup and volumetric oxygen mass transfer coefficient was analyzed.The experimental results show that baffle width and diamond angle have significant effects on both first and second stages of the reactor.When the diamond angle is 45°,the gas holdup in each stage reaches its maximum.At superficial gas velocity of 0.009 3～0.018 5 m/s,the volumetric oxygen mass transfer coefficient is the highest when the baffle width is 17 mm,while at superficial gas velocity of 0.023 0～0.027 8 m/s,it is the highest when the baffle width is 25 mm.Finally,empirical correlations for gas holdup and volumetric oxygen mass transfer coefficient were established,which can accurately predict the performance of the two-stage internal loop reactor with diamond-shaped internals,providing a feasible solution for mass transfer enhancement and an important basis for the rational design of internal loop airlift reactors.