*Screening out the larger particles with the chaffer and sieves
*Blowing out the lighter particles with a fan blast, or
*Screening out the smaller particles in a recleaner
The impact of grain breakage and fine materials on all aspects of the system has resulted in the need to clean grain.
The modern combine harvester produces remarkably clean grain compared with the manual and partially mechanized processes.
Cleaning decreases the airflow resistance, increases airflow, and increases the cooling rate of the grain if aeration is used.
For good storage the chaff, dust and straw must be removed. Broken and foreign grains should not be present: the former encourage insect attack, the latter lower market value.
Broken grains, grain dust and other fine grains have the greatest effect in the performance of insect control interventions.
A typical grain cleaner, often called a scalperator or scalping machine, consist of two parts, a shaking screen and a fan, driven from the same more. Straw and other large objects are removed by screening and the dust and other lightweight material are blown out by aspiration.
The amount of grain cleaning required prior to storage involves the factors of risk to grain deterioration as a result of mold and insect invasions and the costs associated with maintaining quality.
Grain cleaning
