Definition
Sanding mixing and dispersing multi-purpose machine is a general laboratory equipment that integrates grinding, mixing and dispersion functions. It mixes, refines and homogenizes samples through mechanical force, and is widely used in sample preparation in materials science, chemical industry, coatings, electronic pastes, ceramic glazes and other fields.
How it works:
The core working principle of the device is based on the shear and impact forces generated by a high-speed rotating agitator or abrasive media. In stirring or dispersion mode, the high-speed rotation of the rotor causes the sample to form strong turbulence in the vessel, resulting in uniform mixing of liquid and solid particles or breaking of aggregates. In the grinding mode, the equipment is usually equipped with a closed chamber equipped with grinding beads, which drives the grinding medium to move at high speed through the stirring shaft, colliding and rubbing the sample particles to reduce their particle size to the target range.
The kinetic process involved can be described in part by the relationship that the shear rate is directly proportional to the rotor linear velocity, while the particle breaking efficiency is related to the energy density of the input and the filling rate of the grinding medium. Energy input can be expressed as:E = k ∫ τ γ̇ dt, among themEfor energy,τfor shear stress,γ̇is the shear rate,kis the coefficient associated with the system.
Measurement and evaluation methods
The evaluation of the treatment effectiveness of equipment is usually based on relevant industry standards or accepted methods. The main measurement objects include particle size distribution, median particle size, dispersion stability and viscosity change of the treated sample. The particle size distribution can be determined by laser diffraction or dynamic light scattering; The dispersion stability can be evaluated by static observation of stratification time or centrifugal sedimentation experiments. Viscosity is measured using a rotary viscometer. During operation, key parameters such as processing time, rotor speed, temperature control, and the ratio of media to material should be recorded.
Influencing factors
The treatment effect of the equipment is affected by multiple factors. In terms of mechanical parameters, the shape and linear speed of the rotor or agitator directly affect the shear strength; In the grinding mode, the material, particle size, density and filling rate of the grinding medium have a significant effect on the grinding efficiency. Process parameters include processing time, temperature control, and the solids content and initial viscosity of the material. The material properties themselves, such as particle hardness, toughness, and wettability in the liquid phase, also determine the final degree of refinement and dispersion. In addition, the geometry of the vessel has an impact on the flow field morphology of the fluid, and improper design can lead to uneven handling.
Applications:
The application of the sanding mixing and dispersing multi-purpose machine covers a variety of industrial and scientific research fields. In the coatings and inks industry, it is used for efficient dispersion and stabilization of pigments; in the field of new energy, participate in the homogeneous mixing of battery cathode and anode paste or conductive paste; In the ceramic industry, it is used for fine grinding of glaze and body raw materials; In the preparation of composite materials, the uniform distribution of nanofillers in the matrix is realized. It is also commonly used in laboratories for new material formulation research and development and small-batch sample preparation.
Selection considerations
Choosing the right equipment requires comprehensive consideration of experimental needs and equipment characteristics. First of all, it should be clear whether the main function is to focus on dispersion, mixing or grinding, and choose the corresponding modules and accessories accordingly. Attention should be paid to the speed range, torque output, temperature control capability and corrosion resistance of the material contact part. Throughput is another critical factor to match different capacity requirements, from micro to pilot levels. In terms of safety, it should have overload protection, emergency braking and good sealing. Additionally, the scalability of the equipment, the precision of parameter control, and the ease of cleaning and maintenance should also be included in the evaluation.