Difference between Open Circuit and Closed Circuit Grinding Ball Mill

As a common grinding equipment in cement plants and thermal power plants, ball mills have simple operation in the grinding process and good continuous working performance. The ball mill grinding system is divided into open-circuit grinding and closed-circuit grinding in the process. Many manufacturers have questions about these two systems when choosing. Today, I will analyze the differences between the open circuit ball mill and closed circuit ball mill.

Open-circuit grinding system: In the grinding process, when the material passes through the mill once, it becomes the product. The advantages of the open circuit system are: simple process, less equipment, less investment, convenient operation and maintenance. Disadvantages: All materials must reach product fineness before they can be milled. Therefore, when the fineness of the product is required to be fine, the material that has been ground will be over-crushed, and a cushion layer will be formed in the mill, preventing the coarse material from further grinding, and sometimes even the phenomenon of fine powder balling occurs. Reduce grinding efficiency, low output and high power consumption.

Closed-circuit grinding system: When the material is discharged from the grinding, the product is selected by the grading equipment, and the coarse material is returned to the mill for regrind to achieve the required quality of cement. The closed circuit system is the opposite of the open circuit system. The closed-circuit system can reduce the phenomenon of over-grinding; at the same time, the output material can lose part of the heat after conveying and grading. When the coarse powder is returned to grinding, the temperature in the mill can be reduced, which is beneficial to increase the mill output and reduce the grinding power consumption. Generally, the closed-circuit system can increase the output by 15-25% than the open-circuit system, and the product fineness can also be controlled by adjusting the classification equipment, which is more convenient.

Grinding size

The particle distribution of the open circuit system product is wider, while the particle composition of the closed circuit system product is more uniform, with less coarse particles and less fine powder. The clinker calcination reaction speed and the final free calcium absorption are mainly determined by the coarse particles in the raw meal. Therefore, when the particles above 200um are less than 1.5%, the raw meal fineness of the closed circuit system can be appropriately relaxed to improve the mill output and reduce Power consumption for grinding.

With the implementation of the national energy saving and emission reduction policy, the ball mill grinding technology is constantly updated. Therefore, when choosing the ball mill system process, you must choose the open circuit or closed circuit system according to your own different needs, so as to better serve the enterprise. Create economic benefits!