1. Feed Particle Size and Moisture Control
1. Particle Size Classification
Feed particle size must be strictly controlled to ≤25mm. Coarse materials will increase wear on the liner and balls.
Configure a vibrating screen or pre-crushing equipment to ensure uniform feed and prevent particle size fluctuations that affect grinding efficiency.
2. Moisture Adjustment
In wet milling, the moisture content of the material is recommended to be controlled between 10% and 15%. Too high a moisture content can easily cause adhesion to the drum wall, while too low a moisture content can affect flowability.
Adjusting the moisture content using drying equipment or adding grinding aids (such as triethanolamine) can improve grinding efficiency.
2. Optimizing Feed Amount and Ball Ratio
1. Dynamic Feed Adjustment
Use a mill noise sensor (electric ear) or power transmitter to monitor the load in real time and adjust the feed rate to avoid overloading or idling. Traditional ball-to-ball ratio recommendations: Bin 1 should have a "half-ball" exposed (approximately 18% ball-to-ball ratio), Bin 2 should have the material surface level with the sphere, and Bin 3 should maintain a 10-20mm layer of material.
2. Partition Plate and Discharge Cone Design
Optimize the partition plate's open area ratio (grate hole area ratio) to balance material flow rate and ventilation requirements.
Use a half-cut lifting plate or weld a portion of the discharge cone outlet closed to adjust the material layer thickness.
3. Automation and Intelligent Control
1. Fuzzy PID Algorithm
Dynamically adjust the roller press weighing bin weight, mill load, and grinding aid dosage through the DCS system to achieve stable control.
Combining vibration detection (accelerometer) with current monitoring accurately determines the material filling status.
2. Multi-Parameter Collaboration
Automatically adjust the feed rate and grinding media filling ratio (e.g., 60% zirconia balls) when raw coal properties (moisture content, volatile matter) fluctuate. IV. Auxiliary Equipment and Maintenance
Feedback: Install a permanent magnetic separator to reduce the impact wear of metallic impurities on the grinding media.
Lining Plate and Steel Ball Management: Regularly inspect liner wear (replace when thickness ≤ 2/3) and optimize steel ball grading (use large balls for the coarse grinding chamber and small balls for the fine grinding chamber).
