Multiple Bin Storage for Drying
The storage structure for drying (bins) should be so build that they are arranged in multiple bins. Multiple bin storages enable the drying of several lots of seed simultaneously, using the same drying fan or fans. Alternatively, different lots of seeds could be dried successively, with sliding air gates controlling the flow of air to the respective bins. Thus, multiple bin arrangements are particularly advantages when two or more kinds of seeds being are being grown.
The main ducts and laterals, or perforated false floors , may be constructed as previously discussed. When ducts are used the cross-sectioned area of the main duct must be computed on the basis of total volume of air flow. If secondary ducts lead from the main duct, the cross-sectioned area of each secondary duct must be computed just as if it were a lateral. Thus if two ducts lead from the main duct, the cross –sectional area of each must be one half that of the main duct.
The cross- sectioned area of the laterals for each bin must be based on the expected volume of air flow to that bin. Thus, if in multiple bin storage, all the bins will be dried at the same time, then the cross-sectioned area of each lateral will be based on the total number of laterals, in all the bins, since all will participates at the same time in carrying the air streams. However, if bins will be dried individually, then the cross-sectioned area of the laterals must be based on the fact that the laterals in each bin alone may carry all the air output from the fan or fans.
A particularly interesting multi-bin arrangement is to have a double-walled partition between bins, with the space between partitions serving as the main duct.
When the partition wall serves as the main duct, it may be necessary to use two more fans at each end to provide adequate volumes of air. This is particularly true for lage bins involving large quantities of seed to be dried at one time.
The two bin system permits a minimum investment for fan, duct, heater, etc. arrangements involving more bins are convenient in that the fan need not be moved. However, the cost of a main duct can become a very considerable item. If additional bins are added, it is usually preferable to use an additional fan at the other end of the main duct, rather than trying to use one very large fan to dry all the bins at once.