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Conveyor belts are used to move beans in and out of storage to reduce damage that may occur with auger conveyors. Although belt conveyors are more expensive than general grain handling augers, the reduction in damage typically makes the investment worthwhile. Belt conveyors for under‐bin‐flow unloading or for replacement of augers in dryers are custom‐made items. Belt conveyors are usually larger in size than auger conveyors thus require additional space (Uebersax and Siddiq 2012).

Upon delivery to the local elevator, the bean truck loads are weighed and then immediately dumped into a handling pit in the floor of the receiving area. This pit provides for aggregation of the beans for conveyance to subsequent cleaning operations. Again, caution is required in the flow rates and dropping distances of beans to minimize shattering of the dry seed coats (Bingen and Siyengo 2002).

The initial major unit operation is the direct application of high‐velocity air to pass through the beans and lift lighter‐than‐bean material, such as stems, leaves, pods, checked seed coats, and other forms of trash and plant material (Rodiño et al. 2011). A wide array of debris is readily removed from the dry beans during this forced air aspiration. If this material were contained in the beans during long‐term storage, it would have an adverse effect on airflow and moisture content, and the potential for excessive mold growth and subsequent off‐flavor development (Uebersax and Siddiq 2012). Thus, it is important to remove this lighter‐than‐bean material prior to long‐term storage of beans.