Insoluble sulfur (IS) is a core additive in the rubber industry, and its размер частицы distribution directly affects its dispersibility and product performance. Traditional mechanical grinding faces the following challenges:
- Thermosensitivity: IS depolymerizes into ordinary sulfur above 105°C, losing its functional properties.
- Explosion risk: Sulfur dust with particle size <75 μm has a minimum ignition energy of only 1-3 mJ (ASTM E1226 standard).
- Static accumulation: Sulfur friction generates static electricity with a potential >5 kV (EN 1127-1 assessment).
Мельницы воздушные классификаторы, with their low-temperature, inert environment and precise classification capabilities, have become the ideal choice for IS grinding.
Working Principle of the Воздушный классификатор Мельница
Ан мельница воздушного классификатора is an efficient grinding device that combines airflow and mechanical forces. It utilizes high-speed airflow to refine and classify the material. The main working principle is as follows:
Grinding process: After the material enters the mill, the airflow accelerates it to a high-speed state. The collisions and friction between the material and the grinding plates generate shear forces that break the material into fine particles.
Classifying process: The material is classified by particle size using the rotating airflow and classification device. Coarse particles are returned for further grinding, while fine particles are discharged through the classification device.
The uniqueness of the air-classifying mill lies in its ability to precisely control particle size distribution, improving product uniformity and purity. The use of airflow classification avoids issues of over-grinding and material loss common in traditional grinding methods.
Параметры процесса:
| Параметр | Setting Value |
| Feed size | ≤3 mm (after pre-crushing) |
| Classifier wheel speed | 1150–8500 rpm |
| System air volume | 800–1200 m³/h |
| Inert gas | Nitrogen purity ≥99.99% |
The uniqueness of the air-classifying mill lies in its ability to precisely control particle size distribution, improving product uniformity and purity. The use of airflow classification avoids issues of over-grinding and material loss common in traditional grinding methods.
Grinding Process of Insoluble Sulfur
Insoluble sulfur is a химический substance with low solubility and a high melting point, and controlling its particle size is crucial for its final application. The grinding process of insoluble sulfur in an air classifier mill generally includes the following steps:
Material pretreatment: The insoluble sulfur raw material is pre-screened to ensure its particle size is suitable for the mill.
Refining and классификация: In the air-classifying mill, high-speed airflow accelerates the sulfur material to a high-speed state. Through multiple impacts and friction, the material is gradually refined to the required particle size.
Classification and recovery: During the grinding process, the classification device automatically sorts particles by size. Coarse particles are sent back for re-grinding, while qualified fine particles are discharged through the airflow, completing the grinding process.
In this process, factors such as airflow speed, grinding plate speed, and feed rate must be controlled to ensure grinding efficiency and uniform particle size distribution.
Explosion Prevention Technology in the Grinding Process
During the grinding of insoluble sulfur, the risk of dust explosion is high due to its flammability. To avoid this safety hazard, several explosion prevention measures must be implemented in the design and operation of the air-classifying mill:
Atmosphere control:
Inert gases (such as nitrogen) replace air as the airflow medium to reduce the oxygen concentration and lower the risk of combustion and explosion. Nitrogen effectively reduces the likelihood of fire and explosion.
Dust control system:
An efficient dust collection system is equipped to remove dust from the air through collectors and airflow recovery systems, reducing dust accumulation. A negative pressure environment is maintained around the grinding area to prevent dust leakage into the external environment.
Explosion-proof devices:
The air classifier mill should be equipped with explosion-proof devices that meet international standards. Common explosion-proof devices include explosion vents, isolation devices, and pressure relief systems. When the internal pressure exceeds a certain threshold or an anomaly occurs, these devices activate to release the explosive pressure externally, protecting the equipment and operators.
Temperature monitoring:
During the grinding process, friction and airflow speed can cause the temperature of the equipment to rise. Excessive temperatures can trigger a fire, so temperature sensors are used to monitor the grinding area’s temperature in real-time. If the temperature exceeds the set value, the system will automatically alarm and initiate cooling measures.
Electrical explosion-proof design:
The electrical system of the air-classifying mill needs to adopt explosion-proof designs to prevent electrical sparks from causing dust explosions. This includes using explosion-proof motors, switches, cables, and ensuring proper grounding of the equipment.
Operating procedures and training:
Operators must undergo rigorous explosion-proof training to familiarize themselves with the use and maintenance of explosion-proof equipment. Detailed safety operating procedures should also be established, such as regular checks on airflow systems, dust collection systems, and explosion-proof devices to ensure the equipment operates safely.
Эпический порошок
The air-classifying mill of Epic Powder not only enhances the grinding efficiency and product quality of insoluble sulfur but also provides crucial safety features, effectively preventing dust explosion risks. By leveraging advanced air classification technology, Epic Powder ensures a controlled grinding process with precise particle size distribution, minimizing the hazards associated with traditional grinding methods. As grinding technology continues to evolve, Epic Powder’s air-classifying mill will remain at the forefront of efficient, safe grinding for insoluble sulfur and a wide range of other chemical materials.