Dry Grain On The Combine

Are you interesting in refining and marketing the combine-mounted microwave grain dryer? If so, contact Alvin Snaper at Neo-Dyne Research Inc., 1000 W. Bonanza Road, Las Vegas, Nevada, 89106 USA

If you thought the only use for a microwave oven on the farm was to cook macaroni and cheese, think again. Alvin Snaper, an inventor and owner of Neo-Dyne Research Inc., in Las Vegas, Nevada, has another use in mind for them. He sees farmers someday using them on their combines.

And no, not for heating up their lunches. He has a clever idea that would allow a combine to harvest a high-moisture crop and dry it down to an acceptable moisture level using microwave technology. “It works exactly the same way as an ordinary microwave oven,” says Snaper.

Snaper’s microwave grain dryer is designed to be attached to an ordinary combine, turning that Lexion, Deere or other machine into both a thresher and a grain dryer rolled into one. The design allows for grain drying to occur continuously as the machine moves the kernels from the threshing mechanism up to the hopper.

The idea started a few years ago when a consortium of grain farmers in the U. S. Midwest hired Snaper to look into the feasibility of a combine-mounted dryer to improve productivity. “The whole concept was to eliminate post-combine drying,” he says.

Snaper already had more than a few successful inventions under his belt at the time, which made him a good candidate for the job. And as it turned out, he proved his microwave concept could work after building a functioning prototype.

But at first, Snaper found the microwave dryer required an enormous amount of electrical energy, more than could be generated by the combine. That made it impractical. When he decided to make use of the waste heat from the combine engine’s exhaust, things changed. Typically, engine exhaust heat is wasted energy, but not with Snaper’s system.

“By utilizing waste combine engine heat, we brought the microwave power requirements down to a realistic level,” he says. That reduced the electrical demand from the microwave chamber to a manageable 5,000 Watts. In all, the grain spends about four minutes passing through the chamber, then it’s dumped into the combine’s hopper, dry and ready to store.

While using exhaust heat reduced the amount of microwave energy necessary to dry the grain, it had another benefit. The combination of microwaves and hot air complemented each other perfectly. “The microwave dries moisture from the centre [of the kernel] out, while heat dries from the outside in,” Snaper says. That reduces the risk of kernel damage from the drying process. “Grain is less degraded with both [drying sources],” he adds.

Exhaust heat is used to preheat the grain as it starts moving through the drying system, but the design continues to apply it as the grain moves through the drying chamber where the microwave energy is applied, which means the hot air flow from the exhaust also helps carry vaporized moisture away from the grain. That further increases the drying efficiency.

Snaper’s prototype can handle 25 bushels per minute and reduce the moisture content by as much as 10 points. “We came up with a small unit that was suitable for mounting on a combine,” he says.

But while that capacity may not be enough for today’s class 8 and 9 combines, reducing the moisture content by that much means the concept has the potential to greatly extend the harvesting season. And most importantly, “It can be scaled up or down,” says Snaper. So that 25-bushel rate could be boosted to match any combine’s capacity.

However, further development of the prototype stopped when the group that hired Snaper ran out of funds. That left him with ownership of the Canadian patent rights to his microwave dryer. Now he’s looking to sell the technology to anyone willing turn it into a market-ready system. That means despite the exciting potential of this system, it will likely be quite a while before there are any working production models in the field.

$60,000 ADD ON

Snaper envisions the microwave dryer as either an aftermarket add-on, or an option built right onto the combine by a manufacturer. But just how much would the concept add to a combine’s sticker price? “We were looking for a sale price of about $60,000,” says Snaper.

At first that sounds like an expensive feature, but the potential gains from it are enormous. If Snaper’s dryer can drop moisture levels by 10 points, that means producers could turn their combines into a wheat crop that was testing 20-plus per cent and dump dry kernels into the grain cart. Adding that many more combining days to a harvest season could eliminate the need for an extra combine, which would cost a lot more than $60,000.

There is another advantage, too. Eliminating the need to feed propane into a grain dryer in the yard could save thousands more for large-scale growers. Not to mention making that dryer in the yard redundant.

And who knows, maybe with a microwave system on board, you really could tap into the system to cook up some KD right from the driver’ seat!

About the author


Scott Garvey

Scott Garvey is a freelance writer and video producer. He is also the former machinery editor at Grainews.



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