Grain Dryers

One of the various things that we are working on on the farm is the grain dryers. In order to get optimum price at market, grains need to be at specific moisture level, depending on what type of grain. Grain dryers utilize huge axial fans and huge amounts of heat to expedite the drying process.

 The average horsepower of of a grain dryer is about 15, which is about 270 times the strength of your average household fan. However, some of these machines can get up in the range of 75 horsepower, about 1125 times that of the average household fan.

In addition to incredible air speeds heat is also added via a large propane burner mounted inside the fan housing. Average BTU( British Thermal Units ), which is a measure of the heat output capabilities, in a 2300 square foot home is 100,000. A grain dryer can do over 2,000,000 BTU in a space about  500 square feet.

On the farm we have a total of four of these beasts ranging from 15-20 horsepower. In order to prevent a catastrophic explosion these machines must be maintained regularly. Before I was even born we had a grain dryer blow up an entire grain bin. There is still a huge crater in the ground where the bin used to sit, and there is still metal that is lodged in the ground so tight that it can not be pulled out with our tractor. The way these explosions happen is that the circuit that controls the gas shut off malfunctions. This allows the entire grain bin to be filled with propane gas, and the when the machine is ready to begin drying and lights the burner, everything is blown to smithereens in a matter of seconds. However, with proper maintenance, which includes regular inspection, proper cleaning, and regular testing of electrical controls, these machines can be operated safely.