There has been a lot of discussion over the years about how to use aeration fans to get grain into condition over the years. I had the opportunity to listen to two speakers last week at the Agronomy Update at the University of Saskatchewan. Dr. Ron Palmer retired from the University of Regina and Dr. Joy Agnew with PAMI both presented findings from research projects that they are running. Although they have not found a operating system that works to automated aeration fans, they have suggestions as to how you can better use the aeration systems that are on the farms in the area. The studies indicated that there were savings with turning the fans off and on. The studies did not agree on when the best time would be to turn the fans off to obtain optimum drying. The likely reason for this would be the conditions of the location that they were in. Optimum times for drying will be dependent on the air temperature, the relative humidity of the air, the moisture and temperature of the grain, the actual set-up of the bin and the interaction between these factors. All these factors will have an impact on the ability of an aeration system to dry grain. The one area that both researchers agreed on is that aeration can dry grain in storage. The key to making the system work is to make sure that the air that is being put into the bin has less moisture than the air that is leaving the bin. This sounds like it should be easy to do but it is not. To be effective with an aeration system, a producer must understand how much moisture air can hold and how the conditions in the bin will affect the air that is moving through. For the air moving through the bin, warmer air can hold more moisture than cold air. The amount of moisture in air is indicated by the relative humidity and temperature of the air. If the relative humidity and the temperature of the air are known, an actual amount of water that is in the air going into and coming out of a bin can be measured. The amount of moisture going into a bin with the air going into the bin must be lower than the amount of moisture in the air coming out of the bin. If this is not the case, the grain will not be getting dryer. If the air is carrying less moisture per cubic foot than when it is going into the bin, this means that the grain is has increased in moisture. The set-up of the bin and the type of grain that is involved will impact how an aeration system works. All the factors must be understood to allow for an automated system to perform. We are not at this state with our aeration, but a better understanding of how the systems perform will allow us to use aeration systems more effectively. Give me a call if you would like more detail about these presentations.
By Dave Cubbon, P Ag