Closed Circuit Dry Grinding

In order to achieve the desired particle size, the milling under industrial conditions is usually performed in grinding circuits including classifiers that separate the material according to particle sizes. In a closed mill circuit the oversize particles are returned from the post milling processes to be remilled whereas with an open circuit the process has no feedback loop.

In dry grinding systems, the material from conventional crushing and screening operations is subject to coarse and fine grinding primarily in roller mills or ball mills to reduce the material to the necessary product size range.