Clean drying air
Combustion products never enter the drying air — only clean, heated air reaches the grain dryer. This matters most for food-grade and seed grain.
AETERN ECO-TERM · GRAIN DRYERS · SINCE 2013
A grain dryer that dries
with clean air, not smoke
Solid-fuel grain-drying systems. Fuel burns in a closed chamber, smoke exits through the flue, and only clean hot air enters the dryer. No direct contact between the grain and combustion products, and a more predictable drying cost than gas.
- 135 °C outlet temperature
- 300,000 – 3,600,000 kcal/h, power range
- AISI 310S heat exchanger steel
- 2013 operating since
HOW IT WORKS
Two streams that never mix
With direct heating, combustion products go into the dryer together with the hot air. It's thermally efficient, but the grain ends up in contact with flue gases.
In our system, a heat exchanger sits between the fire and the grain. Fuel burns in a closed chamber, flue gases pass through tubes and exit through the chimney. Outside air is heated through the heat exchanger walls and pushed into the dryer by a fan. The two streams are separated by metal and never mix.
The outlet air is clean and hot, up to 135 °C. Automation maintains the set operating mode.
Stable drying air temperature
Automation controls the fuel feed and combustion process, keeping the drying air temperature stable. This helps maintain an even drying regime throughout the shift.
Energy independence
You can dry with whatever fuel is available on site: pellets, wood chips, husks, agro-waste, grain-cleaning waste, firewood, and other biofuels. Less dependence on gas and its price.
A burner matched to your fuel
We match the burner to your fuel — from fine pellets to firewood.
Retort burner
For fuel up to 4 cm: pellets, fine wood chips, husks, coal, and grain-cleaning waste.
V-shaped burner
For non-uniform wood chips up to 8 cm and other loose fuels, including pits, shells, and grain-cleaning waste.
Enlarged door
For manually loading briquettes and firewood.
Special retort burner for straw pellets
Designed for straw pellets, it reduces the risk of fuel caking into dense clinker. Suits farms that want to use their own straw as fuel.
"ISN'T A HEAT EXCHANGER LESS EFFICIENT?"
Direct combustion is more efficient on paper — it can reach 95–98%. A heat-exchanger system runs lower, roughly 70–90% depending on fuel and operating mode. Some heat leaves with the flue gases, but those gases never reach the grain.
Fuel consumption ends up somewhat higher, but the drying air stays clean. For food-grade grain, seed grain, and oil-press feedstock, that can matter more than the difference in fuel use. We calculate the economics separately for every site.
HEAT-RESISTANT STEEL
The heat exchanger is made from AISI 310S — a heat-resistant stainless steel with a high chromium and nickel content. It's built for long-term operation at high temperatures.
On sites already in operation, these heat exchangers run for eight seasons and more. This matters most for the lower tubes — they take the highest thermal load.
WHAT HAPPENS INSIDE
Combustion products never touch the air
Air is heated through the heat exchanger walls. Fire and smoke stay inside the circuit and exit through the chimney.
SOLID FUEL VS. GAS
One dryer, two heat sources
Compare a solid-fuel heat generator with conventional gas drying.
| Criterion | Our heat generator solid fuel | Gas drying |
|---|---|---|
| What reaches the grain | Clean heated air — flue gases are diverted through the heat exchanger to the chimney | With direct heating, gas combustion products go into the dryer together with the hot air |
| Fuel cost | Wood chips, pellets, husks, agro-waste — including your own feedstock. Cost can be calculated in advance | Depends on the current gas price and moves with it |
| Fuel flexibility | Pellets, wood chips, husks, agro-waste, briquettes, firewood — we match the burner to whatever fuel is available | Gas — natural or LPG, depending on the equipment and infrastructure |
| Dependence on infrastructure | Needs a site, fuel storage, and fuel feed | Natural gas needs gas infrastructure; LPG needs tanks and a supply system |
| Fire and explosion safety | Open flame and sparks from the firebox never enter the drying air stream, lowering fire risk | With direct heating, combustion products pass through the dryer; poor maintenance raises fire risk |
| Season cost | Fuel can be bought or stockpiled in advance, and the season's cost calculated ahead of time | Season cost depends on the gas price during the drying period |
Gas is convenient when the infrastructure is already there and the price works. But drying cost tracks the tariff directly.
Solid fuel can be bought on the market or sourced in-house. And with a heat exchanger, combustion products never reach the grain.
Power range, 13 models
| Model | kcal/h | kW |
|---|---|---|
| CHG-300 | 300 000 | 348 |
| CHG-500 | 500 000 | 580 |
| CHG-700 | 700 000 | 812 |
| CHG-850 | 850 000 | 986 |
| CHG-900 | 900 000 | 1044 |
| CHG-1000 | 1 000 000 | 1160 |
| CHG-1250 | 1 250 000 | 1450 |
| CHG-1500 | 1 500 000 | 1740 |
| CHG-1800 | 1 800 000 | 2088 |
| 2×CHG-1000 | 2 000 000 | 2320 |
| 2×CHG-1250 | 2 500 000 | 2900 |
| 2×CHG-1500 | 3 000 000 | 3480 |
| 2×CHG-1800 | 3 600 000 | 4176 |
2× configurations use two modules installed in parallel. Maximum outlet air temperature is 135 °C.
THREE QUESTIONS FOR ANY SUPPLIER
Questions worth asking any supplier
Three simple questions that help you compare equipment quickly, without the sales pitch.
-
What steel is the heat exchanger made of, and how thick is the wall?
Ours: AISI 310S, 12 mm.
-
What fuel and moisture content was the stated efficiency measured with?
By our calculations: roughly 75–85%, depending on fuel calorific value and operating mode. We'll show the calculation for your specific fuel separately.
-
What's the oldest unit still running, and where can I see it?
Uman, 2014. An old-design unit with a reinforced arch is still running there. A site visit can be arranged.
Ask for specifics: steel grade, calculations, and working sites.
CALCULATOR
Run the numbers on your own figures
Enter your dryer's throughput, crop, moisture removal, and your fuel prices. The calculator will show an estimated season cost and compare your options.
The calculator widget will load here
Calculation based on your fuel prices.
This is an estimate. Grain moisture, operating mode, fuel calorific value, and site conditions all affect the final figure. We'll prepare an exact calculation from your inputs.
01 of 04
EIGHT SEASONS, PAID BACK THREE TIMES
Built from scratch — and ordered another one eight years later
Site's challenge «Will it last?»
- Scope of work
- greenfield site: foundation, grain dryer, and heat generator
- Seasonal throughput
- 6,000–10,000 tonnes of grain
- Maintenance
- scheduled; heat-exchanger tubes every 3–4 years
- Result
- a new heat generator ordered after 8 years
After extensive planning of the dryer and heat-generator layout, the entire facility was built from scratch on a greenfield site. We supplied the foundation design and layout for the adjacent equipment and installed the grain dryer and heat generator.
The customer subsequently dried an average of 6,000–10,000 tonnes of grain per season, sometimes more. We continued supporting the site after delivery with scheduled maintenance. Heat-exchanger tubes were replaced every 3–4 years as a normal wear item, not because of a failure.
Eight years later, the customer returned for a new heat generator to replace the original unit. We are buying back the old one for use at our own facility. We are farmers too and know our equipment.
«That unit served its full life and paid for itself three times over.»
Customer, Illintsi verbatim, used with the customer’s permission
02 of 04
FIRST PROJECT IN THE EU
First project in the European Union
Site's challenge «My country and dryer are different»
- How it started
- through an enquiry from a Bulgarian supplier
- Equipment supplied
- 2 heat generators
- Capacity of each unit
- 1,500,000 kcal/h
This was our first project in the European Union. A Bulgarian supplier found us and asked a simple question: “Can you do it?” Our answer was equally simple: “Yes, we can.”
We supplied two heat generators rated at 1,500,000 kcal/h each. They met the requirement and confirmed that customers abroad find us for the same reason as customers at home: operating references.
«Can you do it? — Yes, we can.»
How the project began
03 of 04
4 MW GAS TURBINE RETIRED
Replaced a 4 MW gas turbine
Site's challenge «I have a large gas-fired dryer»
- Previous equipment
- 4 MW gas turbine (approx. 94% efficiency based on fuel input)
- Equipment supplied
- 2 heat generators at 3,000,000 kcal/h each
- Seasonal throughput
- at least 10,000 tonnes of various crops
- Operating duty
- the most intensive duty among our projects
The site previously used a large gas turbine with 4 MW fuel input. This was our first installation of a heat generator on a tower grain dryer, and the customer knew it. He had heard about us from a neighbouring farmer and said, “I have heard about you and know that nothing is impossible for you.”
We installed two heat generators rated at 3,000,000 kcal/h. They comfortably cover the site’s demand, despite the heaviest duty among our installations: at least 10,000 tonnes of various crops per season.
After three years we replaced the tubes, and after five years we reinforced the worn arch with refractory concrete. The temperature dropped by a few degrees but became more stable, as the concrete also retains heat and smooths the operating cycle.
«I have heard about you and know that nothing is impossible for you.»
Customer, Hlobyne
04 of 04
OUR OWN SITE
Our own facility
Site's challenge «Do you use it yourselves?»
- Purpose
- contract drying and experiments
- Status
- dismantled and being relocated to Bulgaria
This is our own facility. We built it for contract drying and experiments because it is easier to test new solutions on our own equipment before offering them to customers.
The complex has now been dismantled because the site is inactive. The equipment is being moved to our own facility in Bulgaria, where it will return to operation.
SITES
Where this is already running
Installations in Ukraine, Romania, Moldova, Poland, and other Eastern European countries.
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IN OPERATION
What it looks like in real life
Videos filmed on real sites.
Click the image to play the video.
Become our partner
We're looking for dealers and installation and service companies in the regions where we operate. We provide equipment, technical support, installation and commissioning training, and materials for your market.
What we need from you
Experience with agricultural or grain-elevator equipment, and the ability to handle installation and service in your region. A warehouse base is a plus but not required.
REQUEST
Send us the details — we'll prepare a calculation
We need three things: dryer throughput, crop, and inlet/outlet moisture. That's enough for a preliminary power and model match. We'll clarify the rest on a call.
Bulgaria — head office
23A Emanuil Manolov St, Varna, 9010
+359 887 999 543
Kyiv — B2B-Agro office
03150, 72 Yamska St, office 201
+38 (096) 116 9999 · +38 (095) 116 9999 · +38 (093) 116 9999