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Dryeration and in-storage cooling for corn drying

Here, you’ll find guidance about two methods of cooling corn after drying – dryeration and in-storage cooling – and strategies for successfully drying grains for harvest.

The typical high-speed drying process rapidly reduces corn moisture content using heated air and then rapidly cools the corn in the dryer before transfer to storage (Figure 1).

Dryeration (Figure 2), a process developed at Purdue University in the late 1960s, modifies this high-speed drying process by transferring hot corn to a cooling bin, eliminating in-dryer cooling. Advantages include increased dryer capacity, reduced fuel consumption and better corn quality.

In-storage cooling (Figure 4) is an alternative to in-dryer cooling. Hot corn is directly transferred to the storage bin rather than a special cooling bin, as in dryeration. In-storage cooling eliminates the extra handling step that is sometimes a disadvantage of dryeration, making in-storage cooling a feasible alternative.

Figure 1: Schematic diagrams for five types of high-speed dryers.

Dryeration

In the dryeration process, hot corn is delivered from a high-speed dryer to a dryeration bin, where it tempers, or steeps, without airflow for at least four to six hours before being slowly cooled. Figure 2 shows the steps involved.

The high-speed dryer’s capacity is increased because the dryer is not used for cooling. A batch dryer eliminates cooling time, and adding a burner to the cooling section of a continuous-flow dryer converts the entire dryer column to full heat.

Figure 2: Dryeration system schematic.
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In-storage cooling

In-storage cooling (Figure 4) is similar to dryeration with one exception: Delayed cooling to allow for tempering or steeping is not recommended. With in-storage cooling, hot corn is delivered to a storage bin equipped with adequate airflow, cooled in the bin and left in storage in the same bin.

Figure 4: In-storage cooling schematic.
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Strategies for both dryeration and in-storage cooling methods

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Warning: Flowing grain is dangerous

Never enter a grain bin or other grain storage area while the grain is flowing. Flowing grain will exert forces against the body great enough to pull the average-sized person under the grain in only a few seconds, leading to death by suffocation.

Reviewed in 2018

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