Study On Flow Field Of Multi-jet Mixer And Smv Static Mixer--Application In Industry Of Ethylbenzene Dehydrogenation

Numerical simulations were performed to study the effects of various geometric and process parameters on the mixing characteristics of model gases undergoing mixing in multi-jet mixers and SMV static mixer.In terms of multi-jet, it is found the friction factor of deflector-type jet is smaller than other jets. The computational fluid dynamics model was validated with the cold mode experimental results. Good agreement between the simulated and experimental results was obtained. It is also found that the Vj/vm, q/Q, jet number and ring channel diameter have significant effects on mixing. It can observed that four-jet mixer can yield better mixing than two-jet, six-jet and eight-jet mixers when q/Q was the same. For the same flow rate, there is an optimum v,/vm for which the mixing is fastest and the total pressure drop is low. The regulation flow can obviously promote the mixing condition of four-jet mixer. There is an optimum ring channel diameter, the mixing is fastest and the total pressure drop is lower. The results presented here are very useful for the preliminary design of multi-jet mixer for low viscosity fluids. Numerical simulation was performed to study the mixing condition of120kt/a styrene six-jet mixer in Industry of Ethylbenzene Dehydrogenation. A new four-jet mixer of280kt/a styrene six-jet mixer was designed.Numerical simulations were performed to study the friction factor and mixing condition of SMV static mixers with large diameter and corrugated plate height. The computational fluid dynamics model was validated with the cold mode experimental results. Good agreement between the simulated and experimental results was obtained. It is found that the corrugated plate height, element number have very significant effects on the friction factor and mixing condition of SMV static mixer. For the same diameter, as corrugated plate height increases (the number of corrugated plate decreases), the friction factor increases and the mixing condition get worse. As the number of element increases, the friction factor remains unchanged and the mixing condition get well. The results presented here are very useful for the selection or design of SMV static mixer in the energy-saving process of ethylbenzene dehydrogenation.