Farmers looking to minimize the risk of grain spoilage in wet, harvesting years like this are looking at grain drying options.

Dr. Joy Agnew is the Projects Manager of Ag Research Services with the Prairie Agricultural Machinery Institute.

She says for every 10° C you can increase the temperature of the air going into the bin, you cut reduce the moisture content by cutting the relative humidity in half.

“Most cereals the target moisture content is, you know, somewhere in the 14 or 14.5 per cent range, oilseeds is 9, 10 or 11 per cent, pulses actually range anywhere from 13 to 16 per cent.”

Farmers, who don’t have grain dryers in place, may want to look at adding supplemental heat to natural air drying.

The first step is to use heat to draw moisture out of the grain and into the air that is in the pockets around the kernels, and then use moderate airflow rates to move that moist air up and out of the bin to avoid spoilage.

She notes it’s important to make sure there is adequate ventilation at the top of the bin to allow that moist air to escape.

“You have to match your temperature increase or your water or your drying rate with the CFM’s (cubic feet per metre); or the ability to actually push the water out of the bin. That is the critical thing using supplemental heat; the hotter is not always the better.”

In the last few years more farmers have started investing in larger and larger grain bins, Agnew says, keeping grain in the larger bins in top condition can be more challenging.

“The bigger the bin is and the greater the depth of grain the harder it is to push the required quantities of air through it. So, we are seeing over and over again that it is practically impossible to achieve that .75 or 1 CFM per bushel required to get a decent airflow rate for drying.”

Agnew says it’s important that farmers realize that with any grain depth greater than 20 feet, you’re not going to be able to get the air moving through it, even with a 10 horsepower fan.

More information on crop storage can be found here.


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