Читать книгу Dry Beans and Pulses Production, Processing, and Nutrition онлайн

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Steel bins are arguably the most common and are available in different sizes (height and diameter). These are used in both elevator and on‐farm systems. Steel bins are relatively simple and can be easily installed on site. They are positioned on a poured support footing, and side walls are made by bolting curved sections of corrugated steel into place to form a circular bin structure. Successive tiers are added to the designated height, and a steel roof cap is bolted in place. These bins are equipped with mechanical aeration systems and belt conveyors that deliver beans into and out of bins. All of these facilities are equipped with bean ladders (generally, a spiral chute or alternating plates in a zig‐zag formation) that allow the beans to descend into the silo or bin with minimum damage (Roberston and Frazier 1978).

Dry beans may be stored in pallet‐sized tote boxes constructed of either wood, cardboard, or polypropylene sacks each containing up to one ton of product. These systems provide direct and flexible handling (using a forklift truck) of small lots without excessive bean movement, thus reducing seed coat checking. It is common for beans with highly differentiated quality standards, such as dark and light kidneys, cranberry, and the limited quantities of specialty beans such as yellow eyes, soldier bean and heritage varieties to be handled on‐farm and in local elevator facilities using individual tote storage and handling. Totes may be carefully off‐loaded to bagging systems or shipped directly to the end users (Roberston and Frazier 1978; Uebersax and Siddiq 2012).