US based start-up DryMax Solutions have developed a grain drying system that uses radio waves in a bid to maintain quality and keep costs down.
Grain drying systems are commonplace on many UK arable farms and have proven their worth in some of the wet seasons we have seen over the last few years
Images from the summer of 2012, when combines became bogged down and operators struggled to haul grain trailers out of fields, will last long in the minds of many growers.
On some of the biggest setups there is such a large acreage that grain drying is carried out without hesitation, and crops are brought in at moistures well over 20%.
However, for many producers there is a fine balance to be struck between spending money drying a wet crop and the risk of losing quality by leaving it in the field to dry.
However, this could be about to change as the DryMax system aims to slash grain drying costs by using radio waves to dry grain.
Traditional methods
Most of the dryers currently found on UK farms are either continuous flow systems or drying floors.
A continuous flow system work by moving the grain through the dryer using a series of chains and conveyors, it then draws hot air from a series of burners through the grain to dry it. Once dry it then goes into storage.
Drying floors consist of a raised wooden floor with a tunnel through the middle: The system uses fans to blow air down the tunnel and out under the floor to slowly take the moisture out of the crop.
The advantage of drying floors is that you can keep tipping on the floor and are not going to be held up by the capacity of the dryer.
The crucial issue with both systems is cost: When drying grain using a drying floor, it costs roughly £1/tonne for every percentage point of moisture you take out, and with a continuous flow dryer that can be as much as £1.50/tonne.
Whilst this may not sound much, when multiplied across hundreds or thousands of tonnes the numbers soon start to add up.
When this is twinned with rapidly rising energy costs, the money farmers spend on drying grain can have a real impact on margins: In the last twenty years energy costs in the UK are reported to have tripled.
There are other issues with conventional dryers: Drying with heat can lead to a potential loss of quality – protein can reduce at high temperatures and there is a risk of grains cracking.
Continuous flow systems can lead to uneven drying, or even overdrying, which can prove costly, with a 30% increase in costs when drying to 13% rather than 14%.
Radiowave drying
DryMax appear to have found a solution to many of these drawbacks by swapping out the use of heat for radio waves.
Whilst radio waves are regularly used for drying a variety of applications in the industrial sector such as ceramics, fibreglass, foam, and paper, they are a novel concept to agriculture.
The process is very simple, and the dryer essentially works in the same way as the microwave in your kitchen.
It follows a similar method to a conventional continuous flow system, using a tower design that allows grain to flow through it and large quantities to be dried per hour.
Like traditional tower systems, the grain is pumped to the top and then uses gravity to let the grain flow down through it to the bottom auger or belt.
Unlike with conventional methods, radio waves dry the grain from the inside out: The radio waves penetrate each individual grain causing the water to move out from the inside, then low energy fans push the moist air away.
This involves very limited heating of the grain, with it leaving the dryer at around only 25?, which means that the water leaves the grain as a vapour rather than as steam.
DryMax said that the system can dry grain from any moisture, but that it is actually more efficient when drying grain from a higher moisture.
Benefits
Founder and CEO of DryMax, Kevin Eichhorn, said that he first came up with the radio wave solution in his attempts to find a way to dry grain without heat, and there are proving to be considerable benefits to this.
Drying the grain using radio waves, and drawing the water out from the inside, is far more efficient, as traditional methods dry grain by making it hot and dry on the outside, whilst it is still relatively wet on the inside.
Avoiding this temperature differential between the inside and the outside helps to maintain quality and reduces the risk of grains cracking, whilst it also dries the crop far more evenly.
Keeping the heating of the grain to a minimum also voids any issues regarding lower germination rates for producers who may be growing a seed crop.
The radio wave system is powered by electric and far less energy intensive than fuelling burners, which could slash the costs of grain drying.
The future
As of 2020, DryMax have radio wave dryers installed and operational on sites across the US and Canada.
Kevin Eichhorn said that DryMax is now looking to move forward from the development stages.
He said: "We are looking for strategic investors to help us roll out; the best path for us is probably through companies that can afford an expensive system."
The cost of the technology is a major drawback at present, with the prototype DryMax tower coming in at close to £250,000: However, Kevin insisted that over time the costs will go down dramatically.
He also said that he expects the technology to move into Europe over the next few years.
"I am looking for 10 farmers to purchase dryers in 2021, who will help us with testing and improving algorithms.
"These will be in the US only, but we could use assistance from a capital or strategic partner to help us move into Europe in 2022," he explained.
"By eliminating carbon for fuel, having no pollution, and reducing running costs, this could align with the goals of a company that wants to jump ahead of the competition."
