In the stone grinding production line or stone grinding plant, to improve the technical efficiency means much for the improvement of ore beneficiation indicators. So how can we improve the technical efficiency of the stone grinding plant? The answer is to adopt the closed circuit grinding technological process.

The reasonable grinding flow means that mineral grains should be discharged quickly from the grinder once they are ground and separated. For the existing stone grinders, it’s very difficult to realize the material grain gradation. Therefore, we usually adopt the classifier or fine screener to gain the qualified granularity grade and those coarse material grains will return to the grinding machine again. This process is called sand return.

In the closed circuit grinding flow, the grinder will add returning sand to the new materials. When more materials pass through the grinding machine, the grinder will run faster and the grinding time will be shortened. The closed circuit grinding process requires the unqualified materials moves into and out of the grinding machine again and again till they become qualified ones.

With a large amount of coarse sand fed into the grinder, the closed circuit grinding flow increases the coarse fraction content of the feeding materials. Besides, the proper sand return will remove the vibration of the new materials and bad influence on the granularity of minerals.

What’s more, the closed circuit grinding technology will prevent the over crushing and coarse grain leakage effectively, which is quite helpful for the later ore beneficiation process.