“BinSpector-CO2 provides the earliest available warning for out-of-condition grain with 24/7 automation, reducing the need for risky bin entry and inspection activities,” says Tim O’Connor, co-general partner, BinTech. “Excess CO2 in the grain indicates negative biological activity, so the BinTech system provides an early alert, putting valuable information in the hands of the grain manager, who can then choose how to respond with aeration, coring, removal, etc.”
However, Maier, a pioneer of the concept, admits that while CO2 readings undeniably detect grain deterioration, interpreting the origination of rising CO2 levels is challenging.
“We have computer models that allows us to predict CO2 levels, but the challenge is correlating what we can predict with a computer model to what we are observing in the storage bin because there are so many variables,” says Maier. “We know the cause is mold and self-heating, but is it because of insects, structural leaks or other defects? We’re still trying to pinpoint how much of the grain mass is affected within a bin and the location of that spoilage.”
In the meantime, Maier recommends monitoring CO2 in conjunction with other management tools and best practices to condition grain.
“Now that these sensors are commercially available, it’s important to note they are not intended to replace best practices,” says Maier. “They’re meant to give you more information and alert you earlier to make better decisions for your business. You still want to use all the tools available, such as temperature cables when aerating to cool grain, but you may find you don’t need as many cables if you enhance the bin with CO2 sensors.”
Armstrong suggests using RH and temperature sensors in addition to CO2 sensors which may help identify the location of grain spoilage.
“If you see higher CO2 levels in the headspace of a bin, but its origination isn’t apparent, you may see it indicated by a rise in humidity somewhere in the depth of the grain because it releases moisture as it molds, triggering a rise in RH,” says Armstrong.
Paying close attention to temperature readings relative to CO2 levels also helps indicate spoilage.
“If there is a change from 40 F to 45 F, some may assume that since it’s still cold, there is no problem, but the CO2 monitor could tell you if spoilage is beginning to happen,” says Hurburgh. “Monitoring CO2 in combination with temperature cables can probably sharpen the early detection of quality issues.”
BinTech and GSI are developing a product that combines a variety of grain management tools.
“The product development horizon for BinSpector-CO2 features potential combinations with other technologies,” O’Connor says. “The idea will be to make data from different sensors available to the user via a single interface, along with expert decision software that recognizes data trends and suggests possible management actions. We continue to explore these sensor ‘fusion’ concepts.”
Using a combination of tools helps paint a complete quality picture. Crompton sums it up best: “You must focus on controlling the two fundamentals for quality in storage: moisture content and temperature. The balance has to be just right so you don’t set up an environment for microbial activity like mold, mycotoxins and insects. Taking a multifaceted approach to grain quality is always going to give you the best return on investment.”