A novel spraying jet type sand collector, which used liquid or gas to be carrier and had an injection mouth and a suction mouth at the collecting port, was designed by author. This equipment can be applied not only for collecting and separating of sand and grains, but also for separating the mixed grains with different sizes or specific gravities. The principle of this equipment was injecting fluids to fluidizing sedimentary layer of sand first, and then utilizing suction flow to collect particles. The process of injecting, suction and collecting was influenced by a lot of parameters, such as the structure of the equipment and the physical characteristics of particles in sedimentary layer. In this study, On account of characteristics of particles with different density or sizes in multiphase fluids, a sand collector with 6mm diameter of injection mouth and 30mm diameter of suction mouth at the collecting port was proposed, which used water as be the carrier and can set the speed of spraying flow and suction flow. The density similar glass beads with diameter between 56.5μm ∼ 855μm and the size similar volcanic ash particles were selected as the research target. The study was carried out on the influence of two sedimentary layers with different characteristics of particles on the volume of fluidization zone (FZ) and the maximal diameter of FZ surface, and on the influence of spraying flux and suction flux on the effect time with sedimentary layer and the volume of FZ. It was found that particles with 200μm had the optimal fluidization characteristics which had no relationship with particle shape characteristics. Although two kinds of particles had similar volumes of FZ, the difference between their diameters of FZ surface was relatively large, which was induced by the difference between their flow abilities.