Pre-cleaning system for providing purification of hazelnut from foreign substances

A pre-cleaning system for providing a purification of an unshelled hazelnut at least partially from foreign substances before a processing of the unshelled hazelnut, wherein the pre-cleaning system comprises:

• at least one first separation unit where the foreign substances are sieved and separated, wherein the foreign substances are outside acceptable dimensions of the unshelled hazelnut,
• at least one second separation unit, wherein the at least one second separation unit is positioned in a vicinity of the at least one first separation unit and is configured to provide a separation of foreign substances by means of an artificial air flow provided in at least one flow path provided thereon, wherein the foreign substances have a specific weight lower than a specific weight of an acceptable unshelled hazelnut,
• at least one third separation unit, wherein the at least one third separation unit is positioned in a vicinity of the at least one second separation unit and is configured to provide a separation of foreign substances by means of the artificial air flow and convection, wherein the foreign substances have a specific weight higher than a specific weight of the unshelled hazelnut.