Experimental Study of Grain Dryer Noise Emissions

There is increasing interest in the environmental noise emissions from grain dryers and the potential impact of practical noise pollution mitigations such as barriers adjacent to dryers. Grain dryers are an essential part of grain production in many parts of the world, including Ontario, Canada. Most dryers are large, stationary units that include a burner to provide process heat and a fan or blower to move heated air through the grain being dried. This study measured sound levels at a range of distances from multiple grain drying facilities in Ontario, Canada, over two drying seasons. It was found that the sound level at a given distance varied substantially, depending on the dryer type and presence of blocking features such as grain bins or buildings. Noise emissions did not necessarily correlate to the size or drying capacity of the facility, with some smaller top dry dryers having higher noise emissions than other much larger tower dryers. Targeted investigations of the impact of practical remediations in the form of physical sound barriers showed sound level reductions were possible that were similar in magnitude to those achieved by highway sound walls along roadways, with most sound reduction being at higher frequencies.