The separation of liquid/solid and liquid/liquid heterogeneous mixtures mainly involves solid-phase particulate materials and liquid-phase materials.
The mechanical separation process is mainly a physical process, and the quality of the separation mechanical separation performance has a great relationship with the physical properties of the material to be separated. For example, the gravity sedimentation or decanter centrifuge for separation by sedimentation principle is closely related to the particle size distribution of solid phase particles, solid phase density, particle shape, and liquid phase density, viscosity and surface tension. The applicable range of various sedimentation separation machinery is also divided according to the nature of the material. Various filtration machines separated by filtration methods are related to the particle size distribution of solid-phase materials, the compressibility of materials, the shape of particles and the specific surface area of particle groups, as well as the viscosity of liquid phase, surface tension and the relationship between solid and liquid phases. Affinity and so on are closely related. For simplicity, the sedimentation rate of the solid-phase suspended particles in the liquid phase and the formation rate of the filter cake of the suspension filtration can be measured, so as to comprehensively reflect the physical properties of the material and determine the difficulty of the material.
According to the material characteristics reflected by sedimentation and filtration tests, it can be used as the basis for selecting the type of separation machinery.
Some special properties of the separated materials and some special requirements for the separated products must be considered when selecting models, such as:
1) When the liquid phase is volatile or easy to cause explosion and flammable materials, vacuum filtration cannot be used, and it is required to be sealed and explosion-proof.
2) Materials with strong corrosiveness have special requirements for the selection of separation machinery materials.
3) When the hardness of the solid phase particles is large, the selected separation mechanical material is required to have good wear resistance.
4) The material to be separated, whether it is solid phase or liquid phase, if it is a precious material, requires a high recovery rate.
5) When the solid phase material is a crystalline product, it is required that the degree of crystal breakage during separation is low. This has special requirements for the structure of the separation machine and the discharge method and method.