Definition
The dispersion, grinding and stirring multi-purpose machine is a general laboratory equipment that integrates dispersion, grinding and stirring functions. It realizes efficient mixing, refinement and homogenization of samples through mechanical and fluid dynamics principles, and is widely used in sample preparation and preparation processes in chemical, coating, food, materials science and other fields.
Principle
The core working principle of the equipment is based on the shear and impact forces generated by high-speed rotation. The motor drives the spindle and drives the work head (such as the dispersion disc, grinding rotor, or stirring paddle) in high-speed motion through the sample. When the working head rotates, its edge exerts a strong shear action on the sample, causing the particles or droplets to be torn and refined; At the same time, the resulting vortex and circulating flow promote overall mixing. For grinding functions, it is usually used with an abrasive medium (such as zirconium beads) to further reduce the particle size through collision and friction. The basic fluid shear rate can be approximated as:γ = v/h, among themvis the linear velocity,hIt is a shear gap.
Measurement and evaluation methods
Equipment performance is usually evaluated according to relevant industry standards (e.g., ASTM D6589, ISO 1524) and practical application requirements. Key measurement parameters include dispersion fineness, particle size distribution, mixing uniformity, and processing efficiency. The fineness can be determined by the scraper fineness meter; particle size distribution is characterized by a commonly used laser particle size analyzer; Mixing uniformity can be assessed by sampling titration or spectral analysis; Efficiency is measured by the processing capacity and energy consumption per unit time. Standardized procedures are followed, including fixed speed, time, and sample volume to ensure comparable results.
Influencing factors
The treatment effect of the equipment is affected by multiple factors. In terms of mechanical parameters, the shape and diameter of the working head, the rotation speed and the power determine the shear strength and processing range. Process parameters such as processing time, temperature control, sample viscosity and solid content directly affect the final fineness and uniformity. Material properties such as particle hardness, fluidity and solvent properties can also change the processing efficiency. In addition, auxiliary functions such as vacuum defoaming or cooling systems play a key role in certain applications.
Applications
The equipment is suitable for laboratory and pilot-scale processing in a variety of industries. In the coatings and inks industry, it is used for pigment dispersion and stability testing; In the preparation of nanomaterials, fine grinding and surface modification of particles can be realized. used in the food industry for emulsifying sauces or homogenized suspensions; In the chemical industry, it is commonly used in catalyst preparation or resin blending. Its versatile design allows a single device to adapt to different process needs, improving laboratory space and resource utilization.
Selection considerations
Technical parameters and experimental requirements should be comprehensively considered when selecting. First, the main processing function (dispersion, grinding or stirring) and sample properties (such as viscosity and corrosiveness) are clarified. secondly, pay attention to the key indicators of equipment, including speed regulation range, maximum torque, material corrosion resistance and working capacity; Extended features such as digital controls, data logging, or security can also impact the long-term experience. It is recommended to refer to the safety and performance requirements of laboratory equipment in international standards (such as IEC 61010) and conduct verification tests in combination with actual samples to ensure the matching of the equipment.