Ken Hellevang, NDSU Extension grain drying specialist, offers the following how-to advice on drying and storing wet soybeans.
Soybeans at 18% moisture, could be stored about 50 days at 50 degrees. Allowable storage time is reduced to 25 days at 60 degrees and is extended to about 90 days when the temperature is 40 degrees F.
Not much natural air drying will occur in October and November in North Dakota. It would take about 70 days to dry soybeans at 18%. Adding supplemental heat to raise the air temperature by 5 degrees will permit drying the soybeans to about 11 percent moisture in about 55 days. Only about one-half of the beans would be expected to dry by mid-November, when outdoor temperatures become too cold to dry efficiently. Adding heat would cause the beans on the bottom of the bin to be dried to a lower moisture content and it would increase drying speed only slightly. He suggests cooling the soybeans to between 20 and 30 degrees for winter storage and complete drying in the spring. Start drying when outdoor temperatures are averaging about 40 degrees.
Soybeans can be dried in a high-temperature dryer, but the plenum temperature needs to be limited to minimize damage to the beans. Refer to the manufacturer's recommendations for maximum drying temperature. Typically the maximum drying temperature for nonfood soybeans is about 130 degrees. Even at that temperature, some skins and beans will be cracked. One study found that with a dryer temperature of 130 degrees, 50-90% percent of the skins were cracked and 20-70 percent of the beans were cracked. Another study found that 30% percent of the seed coats were cracked if the drying air relative humidity was 30%, and 50% of the skins and about 8% of the beans were cracked at 20% relative humidity. Food soybeans and seed beans must not have damage to the seed coat, so natural-air or low-temperature drying is the preferred drying method, Hellevang says.
Source: NDSU Extension Communications