Farm Technology: Corn Drying
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Normally when you talk farm technology it’s all GPS, auto-steer tractors, and mapping! But I’m going to talk Farm Technology: Corn Drying. It’s been around for years but it is important and the technology used changes and improves all the time!
We harvest, dry if necessary, and store a lot of corn! So testing corn moisture and drying it correctly is very important to ensure the corn stores properly.
We store corn for several reasons:
- the facilities improve our harvest capabilities
- allow us to (attempt to) manage the market
- store to feed our livestock.
This is our corn dryer.
The center of the dryer is empty, the corn is in the plenum, a band about 18″ wide on each side the full length. The corn enters the top of the dryer and exits the bottom. It runs on LP gas, the burners create heat and the fans force that heat into the dryer and through the grain, heating/drying the corn without damaging it by evaporating the excess moisture inside the corn kernels – how long you leave the corn in the dryer dictates how much moisture is removed and subsequently how dry the corn becomes. The time and heat needed changes depending on many variables, including beginning moisture, variety and type of corn, and ambient temperature.
We can change the operating temperature, normally 170-190 deg and/or the speed that the dryer is unloading, this affects the amount of time the corn is in the dryer. Our dryer is continuous flow, meaning it is always loading and unloading. The time from the moment a bushel enters till it exits is a “pass”, and can be anywhere from 20 minutes to 90 minutes. There are also “batch” dryers, they load, dry the load, then unload the entire dryer full, much like a clothes dryer. The continuous flow is more like a rolling or conveyer oven, where the food bakes while slowly rolling through.
Farm Technology: Corn Drying
Corn is generally harvested anywhere from 28% moisture down on our farm, ideal storage moisture is 15-16%, and the price we receive upon selling is based on 15%, water, the price for higher moisture is discounted to account for the extra water. We test moisture on every load of corn that comes into our bins as we are unloading from the semi, its tested hot coming out of the dryer and then tested again when it cools.
Managing all the variables is where it get complicated. You must know the harvest moisture, this requires a moisture tester.
When farmers 75 years ago were deciding when to pick corn, when it was harvested as ear corn, they would toss 3 ears in a stock tank. If they floated, it was time to go!
The moisture testers we use have evolved a lot over the years from a stock tank, to testing by biting on a kernel of corn and making an educated guess to a computerized one that does most of the work for us!
It uses infrared technology, it then analyzes the corn (for all I know using magic!!) and then reports the temperature, moisture, and test weight of the sample. This tester is also used to measure the moisture and temp of the corn coming out of the dryer. We dump hot, meaning the corn comes out at 110-150 degrees, then cool in the bin. This increases the capacity, in bushels per hour, that we can process. If the corn is too hot, or too dry, or too cool and wet, we can make adjustments as necessary.
We used to keep a running log of the dryer “run”. Meaning 2 to 4 times per hour, we would manually pull corn from the dryer, test it, and record the results and time on a handwritten log, so we knew how accurate our adjustments were. This was time-consuming and meant that someone needed to be constantly watching the dryer. We eventually added a computerized controller, which does this for us, at much more frequent intervals, and makes changes to the dryer itself.
Meet Calc-U-Dri! It is constantly measuring the moisture, gives us an instant readout, as well as prints a record every 5 minute. If we are gone to the field, we can come in and check on the “run”. If the corn starts to run cold and wet, it slows down, if it runs hot and too dry, it speeds up to correct.
It sounds so controlled and precise describing it, but it really has so many things that affect the end result, it still requires a bit of luck.
I tend to think of our dryer a lot like a programmable crockpot!
While your crockpot is cooking supper you can run kids around or if your lucky take a nap. Our dryer and Calc-U-Dri allows the person running the dryer to do other things on the farm while the corn is drying.
Food is lots more interesting than corn drying here are some links to a few of my favorite crock pot recipes:
Crock Pot Broccoli Cheese Soup
Creamy Crock Pot Mac and Cheese
Also, check out the recipes and the crockpot tab for more great ones!
This post is sponsored by the Indiana Corn Marketing Council. But all the thoughts are my own!