Mixer can mix many kinds of materials uniformly. Especially in pharmaceutical industry, different ingredients can be mixed in order to increase their contact area, promote chemical reaction and speed up physical change. For example, mixing machinery can help granular solutes’ dissolving in solvent.
Common mixing machinery can be classified into four types: machinery to mix gas with low-viscosity liquid, machinery to mix medium- or high-viscosity liquid with paste, machinery to mix thermoplastic materials and machinery to mix powder with granules. The mixer for powder or granules works intermittently. And there are V-blender, 3D mixer and slot mixer on the market. Besides, differing in mixing performance, there are ideal mixing, random mixing and no mixing at all. In this case, which kind of mixing machine can we use for different conditions?That is to say,how to choose mixer as per the situation of various materials?
1) Some powder or granules are poorly fluid and attach to each other easily. They need to be pressed or ground mechanically. Therefore, slot mixer is suitable;
2) For those material whose fluidity is not bad but ingredients’ proportions are different, single rotation is not enough. Only 3D mixer or multi-dimensional mixer can mix materials uniformly in multiple dimensions;
3) The rotation of container itself can mix granular materials of good fluidity well by repeated overturning. As a result, V-mixer is recommended. 
