Definition
Dispersion homogenized emulsifier is a kind of laboratory equipment used to efficiently mix two or more heterogeneous liquids, solid particles and liquids to form a uniform and stable dispersion system. It realizes the refinement, homogenization and emulsification of materials through mechanical action, and is widely used in the research and quality control of chemical, food, materials, cosmetics and other industries.
Principle
The core working principle of the device is based on high-speed shear and hole effect. The motor drives the rotor to rotate at high speeds within the stator, creating a strong mechanical shear force. When the material passes through the narrow gap between the rotor and the stator, it is subjected to strong shear, impact and tearing, and the large particles are quickly broken. At the same time, the high-speed rotation forms a negative pressure area locally, generating a hole effect, and the shock wave formed by the rupture of microbubbles further promotes the dispersion of materials. The whole process can be described as a combination of mechanical energy and fluid kinetic energy, and its shear rate is related to the rotor linear speed, and the calculation formula of linear velocity v is:
v = π × d × n
where d is the diameter of the rotor, and n is the rotor speed.
Measurement and evaluation methods
The evaluation of the emulsification effect of dispersion homogeneity is usually achieved by measuring the particle size distribution, dispersion stability and uniformity of the product. The laser particle size analyzer can be used to measure the characteristic values of particle size such as D50 and D90 and characterize the degree of refinement. Centrifugal sedimentation or static layered observation can be used to assess the physical stability of dispersed systems. Microscopic topography can be observed by light microscopy or scanning electron microscopy. In addition, viscometers can be used to monitor changes in material rheological properties before and after treatment, indirectly reflecting the homogenization effect.
Influencing factors
The emulsification effect of dispersion homogeneity is affected by multiple factors. Equipment parameters include rotor speed, rotor and stator clearance design, processing time and number of cycles. Material properties such as initial particle size, phase volume ratio, viscosity, and interfacial tension also significantly affect the final result. In terms of process conditions, the treatment temperature, feeding sequence, and the addition of surfactants and other additives need to be comprehensively considered. These factors are often interrelated and require experimental optimization to determine the appropriate conditions.
Applications
In the food industry, the equipment is used for the preparation of sauces, dairy products and the homogenization of beverages. The cosmetics industry uses it to produce creams, lotions, and other stable emulsion systems. It is commonly used in the chemical field for nanomaterial dispersion, coating color matching and the preparation of polymer composite materials. In scientific research, it is a common tool for simulating production processes, optimizing formulations, and developing new materials.
Selection considerations
When selecting the material, the physical and chemical characteristics, target particle size range and processing amount of the treated material should be comprehensively considered. For high-viscosity materials, choose a model with sufficient torque and pay attention to the heat dissipation design. If you are dealing with sensitive materials, you need to pay attention to temperature rise control, and some models can be equipped with a cooling kit. Modular design of the tool head assembly to adapt to different process requirements, such as coarse dispersion or fine emulsification. In addition, the equipment material needs to be selected according to the corrosiveness of the material, stainless steel or special coating, and the easy-to-clean design helps to reduce cross-contamination. Operational noise, safety protection, and compliance are also aspects that need to be evaluated in the actual selection.