Stationary Drying Plants AgroDry
The innovative air duct system of the STELA Biturbo technology reduces the required hot air volume by up to 40 % and thus lowers the specific energy consumption by up to 15 % compared with conventional drying plants with active heat recovery The fresh air (1) is aspirated in the lower area of the drying plant, heated up by a gas line burner (2) and led into the lower drying section, the product area (4), together with preheated air from the cooling zone (3). The hot air temperature can be adjusted completely independent from the upper temperature zone. The higher tempered exhaust air (5) from this zone is collected and led into the upper zone of the drying plant by means of an intermediate fan (6). The hot air of the upper drying zone is generated by mixing with preheated supply air (7). This drying air is at first led through the upper wet product zone (8), before it is emitted outside again as exhaust air by an exhaust air fan (9).
Advantages compared with conventional drying plants with active heat recovery:
- Lower thermal consumption (reduction by up to 15 %)
- Reduced air volume
- Improved product quality by alternating ventilation
- Lower dust formation due to exhaust air filtering in the wet product zone
- Lower electric consumption values
Numerous references at home and abroad have proved this since the introduction of the system in the year 2012. Patent applied for.
The stationary agricultural dryer AgroDry® used for drying high-quality agricultural products is an efficient drying system for agriculture and contractors. The modern discharge technologies generate rates constant product moisture. Because of the circulating air and heat recovery optimum energy saving is possible. For the production of the stationary agricultural dryer AgroDry® only high-grade aluminum is used, which makes both indoor and outdoor installation possible. In addition, the aluminum alloy allows a long lifetime of the dryer. There are more than 3.900 stationary STELA dryer all over the world.
Advantages at first sight:
- use of the highest quality materials
- dryer from special aluminum alloy
- high life span
- no upper limit to capacity
- optimum energy savings by circulating air and heat recovery
- sophisticated air guidance, highest possible air saturation
- highly efficient
- flexible modular construction
- dust separation with state-of-the-art technology
- high performance fans and air heating technology from own production
- continual operation for optimal utilization and exploitation
- uniform product moisture by modern discharge technology
- STELA process measuring and control technology, state-of-the-art
- proprietary MSR technology as per latest VDE (German Association of Electrotechnical Engineers) standards
- simple and safe operation by PLC (Powerline Communications)
- suitable for indoor and outdoor installation
- plants with one or several columns; divided operation modes as desired
- exclusively by STELA, mobile versions
- EQtronic for high energy savings
For the design of your drying plant, there are numerous variants, which are assembled individually. According to your wishes, you will receive an optimal design for your application with the suitable components. The following examples will show you some possibilities which can be realized.
The free flowing product is fed into the store tank (1), is conducted by gravity through the drying (2) and cooling elements (3) until it is discharged in batches by the discharge device (4) into the discharge hopper (5). Burner (6) and air heater (7) – direct or indirect heating are optionally possible – heat up fresh air. The exhaust air of the cooling elements is mixed with this air. Thus the whole heat stored in the product is led back to the drying process (energy saving by heat recovery). The largescale hot (8) and exhaust air caps (9) guarantee an optimum air and heat distribution in the dryer column. The hot air flows through the product pile, absorbs moisture and is sucked off from the exhaust air cap by the exhaust fan (10). The dust-laden exhaust air is cleaned in the centro-separator (11) and carried off into the open air. The separated dust goes through pipes to the dust bin or to a bagging device.
Not only the exhaust air from the cooling zone, but also the exhaust air (1) (and thus the contained energy) from the lower dryer elements is recovered by means of a circulating air fan. A pneumatic discharge slide brings about short discharge cycles. By means of pneumatic air flaps (dust separation flaps) (2), installed on the pressure side of the exhaust air fans (3), the air flow is interrupted during this discharge cycle. The same result is achieved by the pneumatic circulation air flap (4) installed at the circulating air fan (1). Blocking the volume flow of both fans (exhaust and circulating air fans) prevents the dust contained in the product from being expelled through the discharge. The share of the total air volume that can be recovered as so-called circulating air depends on the initial moisture of the product which is expected on an average and on the parameters of the ambient air and other factors. Therefore the plants are calculated and designed depending on the final site – e. g. Central Europe, Southern Europe or the Tropics. A dryer in Central Germany, which is designed mainly for maize drying with an average initial moisture of 35%, requires another air distribution than e. g. a dryer in Southern Hungary, where average initial moistures of 20% are to be expected.