Definition
Basket grinding and dispersing machine is a kind of wet processing equipment for laboratory and small and medium-sized production that integrates grinding and dispersion functions. Its core feature is that the grinding medium (such as zirconium beads) is sealed in a liftable basket container, and the high-speed rotating dispersion disc in the basket produces strong shear and impact effects to achieve grinding, dispersion, homogenization and mixing of materials. This equipment is suitable for refining and homogenizing slurries, suspensions, etc., and plays a key role in sample preparation and process development in multiple industrial fields.
Principle
When the equipment is working, the basket containing the grinding medium is lowered into the container containing the sample. The spindle in the basket drives the dispersion disc to rotate at high speed, driving the grinding media to move violently in the basket. The material is sucked into the basket, and is subjected to high-frequency shearing, collision and extrusion between the grinding medium and between the medium and the basket wall, so that the particle size is effectively reduced and evenly dispersed in the liquid phase. After the treatment is completed, the basket is raised, and the grinding medium is retained in the basket due to the screen barrier, so as to realize the automatic separation of the medium and the material. The entire process is usually carried out in a closed system, which is beneficial for reducing volatilization and maintaining stable process conditions.
Measurement and evaluation methods
The evaluation of the treatment effect of basket grinding and dispersing machine mainly focuses on product particle size distribution, dispersion uniformity and process efficiency. Particle size analysis often uses laser diffraction or dynamic light scattering to quantify grinding fineness by detecting characteristic particle size values such as D50 and D90. The dispersion stability can be indirectly judged by observing the sedimentation of the slurry after resting or by measuring the zeta potential. Process efficiency is evaluated by recording the processing time and energy consumption required to achieve the target particle size. Relevant test methods should refer to common industry standards such as ISO 14887 (Sample Preparation-Dispersion Procedure), and specify instrument parameters and testing conditions in the report.
Influencing factors
The processing effect is affected by the interaction of multiple parameters. In terms of mechanical parameters, the linear velocity of the dispersion disc directly affects the shear force, and its design shape affects the flow field and pumping capacity. The material, density, particle size and filling rate of the grinding medium together determine the collision energy and frequency. In the process parameters, processing time, temperature control, and the solid content, viscosity and initial particle size distribution of the material itself are the key variables. In addition, the pore size of the basket screen should be reasonably selected according to the target particle size and media size to prevent clogging and ensure smooth material circulation. Each parameter needs to be systematically matched and optimized according to the characteristics of the material.
Applications
With their efficient, clean and easy to operate, basket grinding and dispersing machines are used in many fields where fine wet processing is required. In the coatings and inks industry, it is used for the dispersion of pigments and fillers to improve color and stability. In the field of new energy, participate in the homogenization preparation of electrode slurry and ceramic slurry. In the electronic chemical industry, it is used for the refining of polishing fluids and conductive pastes. In addition, it is also commonly used in the preparation of samples in cosmetics, food additives, fine chemicals and scientific research institutions to prepare uniform and stable suspension systems or nanodispersions.
Selection considerations
Equipment selection needs to be comprehensively trade-off based on specific process goals and material characteristics. The primary consideration is processing capacity and batch volume, which need to match the different scales from laboratory R&D to pilot scale-up. Secondly, pay attention to the power and speed control range of the equipment to ensure that it can provide sufficient shear energy and adapt to materials with different viscosities. The material compatibility of the basket and the contact parts is critical and must be resistant to chemical corrosion and wear of the material. The degree of automation of the control system, such as lift control, speed and time programming, temperature monitoring, etc., can improve the reproducibility and controllability of the process. Finally, the safety of the equipment and the structural design that is easy to clean and maintain are also practical factors that cannot be ignored.