Study Of Liquid Distribution And Modeling With Gas And Liquid Concurrent Downflow In A Trickle-Bed Reactor

The experimental work was conducted in a plexiglass column of140mm ID packed with glass beads of different diameters (1.9,3.6and5.2mm) by applying air and water as the working system to detect the liquid distribution by three methods: liquid collectors, tracer method and electrical capacity tomography (ECT).(1)The hysteresis phenomenon of liquid holdup and pressure drop exists in case of liquid spreading from a point source, it showed that the hysteresis phenomenon is not obvious at the beginning but same as the liquid uniform feeding when liquid flow full development.(2) Three different detected methods are used to describe liquid radial distribution in trickle bed, the results are consistent:different liquid rates have little influence on liquid radial distribution; liquid radial distribution decreases when gas velocity increased; liquid distribution tends to be uniform along the bed height increased; liquid distribution is more non-uniform with bigger particle size.(3) The boundary condition and initial condition are easy to get for diffusion model by tracer method, this method can also avoid the uncertainty caused by non-hydromechanics factors. The experimental results show that diffusion model is suitable for small particle but forecasts poorly in large particle bed. It considers liquid distribution random for stochastic model. Compared to diffusion model, the simulate result of stochastic model is more accurate and can be used for a wide range of particle size.