Impurities in corn are generally mixed during harvesting, drying, storage, transportation, and pre- processing, including sand, dust, metal, roots, stems, and leaves.

In corn processing plants, screening methods are generally used to remove large and small impurities in the raw materials. This method is simple and reliable and is a common cleaning method in corn processing plants.

In the cleaning process of the corn processing plant, air separation and magnetic separation equipment are also used to remove light impurities and metal impurities in the corn. The whole cleaning process is generally combined in a variety of ways to effectively remove impurities from corn.