Study On The Microfiltration Process With The Ceramic Membrane In A Integrated Reactor

With the development of the catalytic oxidation technology, most of novel micro-sized or nanometer catalysts appeared. The micro-sized or nanometer particle was usually employed in suspension. Thus, its recovery and recycle was a severe problem which was hardly solved by the conventional separation technology. In the paper, a novel photocatalysis-membrane reactor was designed by coupling photocatalysis and membrane technologies, which solved the problem effectually. The study focused on the separation of titanium dioxide from suspension by cross-flow microfiltration in the reactor. The systematic studies have shown that the enhanced microfiltration process was strongly affected by the pore size of membranes and operation parameters. An appropriate method was determined for the selection of membrane pore size and optimal process parameters; Backflushing and turbulence promoters were used to enhance the microfiltration process, the appropriate inserts' configurations and backflushing conditions were obtained; The fouling mechanism of the ceramic membrane was investigated, the suitable cleaning means was also obtained in the paper. The critical size of particles which may deposit on membrane surface was determined based on the force analysis of particles in cross-flow filtration. Then, a physical mechanism of the microfiltration process was established based on the filtrate flux under the backflushing enhanced conditions. Last, a mathematical model was established to predict the change of filtrate flux with time in the microfiltration process based on the conventional filtration theories. The theoretical results agreed well with the experimental datas.