Definition
The stirring and dispersion sanding machine is a compound laboratory and industrial wet processing equipment that integrates high-speed dispersion and fine grinding functions. It uses the same power system and container to complete the strong shear, dispersion and wet grinding of the material sequentially or simultaneously under closed or open conditions, aiming to evenly disperse the solid particles in the liquid medium and further reduce their particle size to the micron or sub-micron level.
Principle
The working principle of the device is based on fluid mechanics versus particle mechanics. Its core process can be divided into two stages. The first stage is high-speed dispersion: the stirring paddle (usually serrated) rotates at high speed driven by a motor, generating strong radial and tangential forces, forming turbulent and high-shear areas, so that the agglomerated solid powder can be quickly wetted and initially dispersed in the liquid. The second stage is fine grinding: a specific specification of grinding medium (such as zirconia beads) is put into the dispersed slurry, and the high-speed movement of the medium is driven by the rotation of the dispersion disc, and the collision and shear forces generated between the media and between the media and the inner wall of the container are continuously squeezed, impacted and frictioned to achieve the finening and homogenization of the particles. The entire process is usually carried out continuously in a closed container with controlled temperature and speed.
Measurement and evaluation methods
The measurement of the treatment effect of the integrated mixing and dispersion sanding machine mainly revolves around the performance index of the final slurry. The core measurement parameters are particle size and its distribution, which are usually measured by laser diffraction or dynamic light scattering. The stability of the slurry can be assessed by measuring the zeta potential or by observing the static settlement time. In addition, the viscosity of the slurry is measured using a rotary viscometer, and the fineness can be quickly checked with a scraper fine meter. For the evaluation of grinding efficiency, the energy input or processing cycle required to achieve the target particle size within a specific time is often used as a reference. The relationship between the performance parameters of the equipment itself, such as power P, torque T, and speed ω, can be expressed as: P ∝ T·ω.
Influencing factors
The final treatment effect is affected by the synergy of multiple factors. In terms of process parameters, the speed of stirring and grinding directly affects the shear force and energy input. Processing time is key to determining the degree of grinding; The temperature control set by the program affects the viscosity and reactivity of the material. In terms of material characteristics, the hardness, initial particle size and target particle size of the original material determine the difficulty of the process. The solid content and slurry viscosity affect the movement and energy transfer efficiency of the medium. The compatibility of the material with the liquid medium is related to the dispersion stability. In terms of media selection, the material density, hardness, diameter and filling rate of the grinding medium directly determine the collision energy and frequency. In terms of equipment structure, the structural design, material, gap size and efficiency of the cooling system of the dispersion disc and grinding chamber all have a significant impact on the treatment effect and reproducibility.
Applications
The mixing and dispersion sanding machine is widely used in fields that require the preparation of high-performance, ultra-fine dispersion systems. In the coatings and inks industry, it is used to prepare pigment pastes to ensure color vividness and system stability. In the field of new energy, it is used for the homogenization and nanoprocessing of lithium battery cathomote and anode paste and conductive paste. In the electronic materials industry, it is used for dispersion grinding of magnetic materials, ceramic pastes, and electronic pastes. In the chemical field, it is used for the efficient dispersion of pesticide suspensions, nanocatalysts, dyes and fillers. In addition, it is also a key equipment for formulation research and small-batch sample preparation in laboratories such as materials science and nanotechnology of scientific research institutions.
Selection considerations
Equipment selection needs to be comprehensively trade-off based on specific process goals and material characteristics. First of all, it is necessary to clarify the processing capacity and select the corresponding volume model according to the experiment, pilot or production scale. Secondly, evaluate the required power, torque range, and speed adjustment capabilities of the equipment based on the characteristics of the target material (e.g., hardness, viscosity, sensitivity) and final fineness requirements. The material of the grinding chamber and contact parts (such as stainless steel, tungsten carbide, ceramic, etc.) must have sufficient hardness, wear resistance, and chemical inertness to meet the corrosiveness and purity requirements of different materials. The accuracy and cooling efficiency of temperature control systems are critical for heat-sensitive materials. In addition, the ease of operation, ease of cleaning, safety measures and whether the equipment can meet relevant industry standards (such as explosion-proof requirements) are also important considerations. It is recommended to verify the suitability of the equipment for a particular process through material testing.