stela laxhuber-product overview

drying technology

Innovation

Competence

Reliability

Made in Germany

drying technology

Editorial

History

Business areas

Market

Consulting, planning

Development, construction

Production

Electrical control technology

Biomass belt dryer

Sewage sludge belt dryer

Digestate belt dryer

Dryer for agricultural products

Mobile continuous-mixed-flow dryer Universal

Mobile circulating batch dryer MUF

Feed-and-turn dryer

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Editorial

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Concentration on the essential.

The driving motive for us at STELA could not be better described. We focus on the technology of drying.

“Merely” dryers? Yes!

STELA wants to deliver its customers the best possible technology; therefore we have concentrated on this single technology. We place our entire expertise in the development of modern drying plants, and these for the widest range of products: Starting from agriculture, through food technology and energy technology, up to disposal engineering. Specialisation on the TECHNOLOGY, not on the branch. This creates synergies.

As well, for many years our company philosophy has been to generate the greatest possible vertical range of manufacture in our area. This also stands on the premise: Service to the customer. This allows us to react quickly to customer requirements, because we simply manufacture ourselves the special parts we need in production.This specialisation on the core business has allowed us to continuously grow for years – nationally just as internationally. By now, STELA drying plants can be found in South America as well as in Central Asia. STELA dryers are used in West Canada exactly as in New Zealand. We are proud to have worked hard for this reputation.However, this also means responsibility.

Responsibility for our customers – they not only want the best technology, but most of all to be attended to with good service.

Responsibility for our suppliers – we insist on adherence to delivery dates, but in return are reliable in commercial processing.

Responsibility for our employees – STELA is well known as guarantee for a challenging and secure workplace. We know that finally the employees are responsible for our technological leadership.

Let us continue on this way together.

Thomas LaxhuberManaging Director

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Tradition, Responsibility, Future

1922 1922 1929 1952 1964

Stefan Laxhuber had already started a small workshop in 1922. With arduous effort, he and his wife Juliane Laxhuber first operated their own production of wind pumps and later, agricultural machinery. At the 50 year mark in the company’s existence, the founder handed over the company to his son

Stefan Laxhuber who, together with his wife Theresia Lax-huber, invested many years of hard labour into his life work. It is thanks to him that the company opened a new business sector – drying technology.

History

19728

1967 1969 1972 1985 1993 1997

Thanks to the creativity and ready engagement of the employ-ees, the company grew many times over and now is among the leading manufacturers of dryers in the world. Today the company is in the capable hands of the third Laxhuber gen-

eration. Just as before, drying technology determines our ex-istence. The national and international growth allows us to look into the future with full competence.

We continue to write our company history: http://www.stela-drying-technology.de/en/company/history/

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Drying technology for storing and processing agricultural products

Business areas

The harvest takes place only during a very short period during the year. Within this time, the drying plants must operate reli-ably and efficiently. Whether it be classical wheat, rye, barley, rice or maize, STELA is ready with the appropriate drying so-lution. Even where drying of crops with high oil content such as rapeseed, sunflower seed or cocoa beans are concerned, we can meet the challenges with our drying plants.

Whether it is a permanently installed stationary or a mobile drying plant – both belong to our special area and are profes-sionally deployed.

Our customers include larger agriculturalists as well as contractors, storehouse operations, cooperatives and also processing operations in the grain sector. We have already created individual technical special solutions tailored to the customer, and done so worldwide – from Ecuador to Mada-gascar.

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One very large business area is drying biomass for manufacturing various fuels. In low-temperature drying in manufacturing plants for pellets, STELA already is the market leader. Here, moist sawdust is dried to the exact moisture level necessary for manufacture of certified wood pellets. One additional application area is power plants, where waste wood from sawmills is burned. If the boiler output is insufficient, STELA fuel dryers reduce the water content to the greatest degree possible so that the degree of efficiency increases

considerable. And just as a side note, the excess heat from the power plant is used for a sensible process – drying – instead of simply being conveyed into the atmosphere. In the branch sewage sludge drying, the increasing problem of sewage sludge of municipalities has been solved. Because agricultural application is problematic, the accumulated sludge is burned in special combustion plants to gain energy. However, burning moist sewage sludge increases nitrous oxide emissions and requires expensive filtering. Drying the sludge significantly reduces these emissions.

Industrial Drying Technology for Manufacturing Fuels

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Efficient Drying - Worldwide

40 Million Tons of Grain per Year

40 million tons of grain per year - this amount is dried with STELA drying plants worldwide. An unimaginable number, yet this is the result of years of hard work. All of our knowl-edge is placed in the complex area of drying technology. If this amount is considered, one recognises how important the energy efficiency of the plants is. Therefore further develop-ment also stands at the topmost position at STELA – for the welfare of our customers and the environment.

Market

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5.3 million tons of water evaporation per year is the figure evaporated by STELA drying plants in the area of fuel dry-ing since 2002 alone. All utilizing only the so-called “waste heat” – energy that would otherwise be emitted into the atmosphere utilized. This waste heat is utilized in about 5.5 TWh – in other words 5,500,000,000 kWh, the equivalent of about 550,000,000 litres heating oil, which would have to be utilized instead! Not only is this waste heat utilized with the help of STELA drying plants; in addition, e.g. in the pellet industry, fuel is generated which is easy to transport – to each end customer. Adding an additional value creation.

5.3 million tons ofwater evaporation per year

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What may we do for you?

Consulting – planning

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If it has to do with drying technology, we are your partner. Which product do you want to dry? In the great majority of cases, we already know it and have the necessary data at hand. Our team would be pleased to advise you as to which solution for your special problem would be best. Yet yours is not an everyday application case? No problem! This is why our laboratory is equipped with a fully automated batch

dryer and elaborate measurement technology. Consequently, we can painstakingly test every product and record all parameters necessary for your future plant. That in itself is not enough for you? You are already in production and need a testing facility? We offer that, too. We would be happy to install a small, continuous-flow belt dryer for multi-day test series at your company, with which you can conduct your own tests then.

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Development, Construction

Engineering - Made in Germany

Well planned is half the victory... Our engineers and designers are sometimes asked, if we have ascertained all the parameters necessary for the drying application. The dryer type must be defined, the size, the type of ventilation and much more. Hereby our engineers use a software, part of which we have developed, to optimize the result. The plant is constructed in 3D-CAD and

together with you, our customer, the interfaces or even design elements are coordinated. The communication channels are short; our project managers stand in direct contact with you, but are also the direct internal contact partner for the construction department. Once the plant has been completely planned, it is released to production.

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Production

Quality - Made in Germany

The core of our philosophy is our own production. In order that the core components are as independent of potential delivery problems as possible, we command a very high pro-duction depth. Our production path begins with custom-cut sheet stock. On CNC-controlled tool machines – exclusively

from major manufacturers – we produce the individual parts for your drying plant from blank sheet. The components are pre-fabricated in the factory in order to keep on-site installa-tion times as short as possible.

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The welded parts are also expertly fabricated. Last but not least, we are one of the few companies to be certified for welding technology according to DIN 18800 Part E.

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Electrical control technology

Expertise in planning and production

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electrical control technology

Over decades, STELA control and electronic technology has established itself as reliable partner for switchgear construc-tion, electrical installation, commissioning and maintenance. With the highest claims to quality, we offer you a diversified

range of electrical engineering, automation technology, pro-cess visualisation, switchgear construction and electrical MSR installation from our own production. We can accept our services according to customer request or as turnkey order.

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Dryer Solutions

Products

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Biomass belt dryer



Dryer for agricultural products


Mobile circulating batch dryer MUF

Feed-and-turn dryer

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Biomass belt dryer

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drying technology

Biomass belt dryer

Reference „Holzkurier/Schnaubelt“

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STELA – Low-temperature belt dryer

Characteristic features of our drying plants

product turning device for uniform final moisture and easy ventilation of the product• multivent system with several directly coupled, low-noise radial fans for continuous air distribution with minimal • pressure loss and sound emissionsguaranteed low dust emission values according to the BimSchG (Technical Instructions on Air Quality), also for • difficult-to-handle productsmodular plant system, which can be expanded easily later on • low thermal and electrical consumption values by optimally synchronized components• design available in three different belt widths for individual adaptation to customer requirements •

1 = feeding station2 = product3 = turning device4 = discharge screw5 = belt cleaning system (dry)6 = fan for belt cleaning system7 = web belt

8 = belt cleaning system (wet) 9 = heat exchanger10 = heat supply11 = external air12 = heated air13 = exhaust air14 = exit air

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STELA – Low-temperature belt dryer

realized capacity range 1 – 50 t/h dry product• more than 400 belt dryers around the world in the most • varying sizesutilization of low-caloric heat with 65°C without reheating • stage feasiblein-house, on-time production of the plants by qualified • STELA staff with permanent quality checksour belt dryers currently dry sawdust for the production of • 5.000.000 tons of pellets per year

Application in the most various industries and production divisions such as:

pellet industry• wood gasification• biomass to liquid (BTL)• fiber board industry• pulp and paper industry•

with products like: sawdust• wood chips• bark• forage, digestate• sunflower seeds• straw• animal bedding•

Germany, 4.7 t/h water evaporation Uruguay, 12.5 t/h water evaporation

New Zealand, 16 t/h water evaporation

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drying technology

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STELA - Low-temperature sewage sludge dryer

With the STELA sewage sludge dryer, the most distinct sludges are dried reliably, energy saving and dust-free down to dry solid con-tents of approx. 95%. The mechanically dewatered sewage sludge is compressed into a rope form on a specially designed granula-tion unit. Finally, the product is placed on a perforated conveyor belt into a pile that can be well ventilated by convection. The product is fed into the dryer tunnel, where hot air flows through it to dry it efficiently.

Mechanical strains are avoided to the greatest extent possible by this process.

1 = product feed2 = granulation unit3 = product4 = turning mechanism 5 = perforated conveyor belt

6 = discharge screw 7 = hot air generation 8 = circulating air duct system 9 = fresh air10 = exhaust air

Characteristic features of our drying plants product turning device for a uniform final moisture and easy ventilation of the product• low thermal and electrical consumption values by proven air circulation system and • optimally synchronized components dryer sizes individually adaptable to the respective conditions and customer needs due to • modular construction

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STELA - Low-temperature sewage sludge dryer

water evaporation capacity 0.2 – 6 t/h or more• more than 400 belt dryers around the world in many various • sizessingle or double belt dryers depending on installation situation• exhaust air scrubber for each plant size• turnkey belt dryers including exhaust air conditioning•

special granulation unit without product back mixing• use of low-caloric heat• reliable, proven technology • high quality, on-time and flexible order development by • in-house production with qualified STELA staff

Type: PBT 2/2500-12, water evaporation 1.250 kg/h Type: PBT 2/2500-24, water evaporation 3.000 kg/h

Type: PBT 1/2500-17, water evaporation 1.000 kg/h

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STELA - Digestate belt dryer

1 = feeding station2 = separator3 = discharge screw4 = heat exchanger

Efficient digestate drying can be accomplished by two different drying processes – Separation and back mixing process.

To the drying principle: digestates are fed into the dryer with a dry substance content between 50% to 25%• optimum distribution by two-fold distribution screw system• product height variably adjustable• drying temperature 60°C – 90°C• convective drying by hot air flow through the product layer• water evaporation capacity of about 0.8 - 1.0 kg water/kWh• th frequency-controlled axial ventilators for operation within optimum efficiency range• air flow through the product layer from above to below → dust content < 10 mg/m³ • special turning device for high product homogeneity• underpressure operation means no leakage•

Characteristic features: highly efficient process for digestate drying• low consumption values• low emissions• high quality end product• thermal capacity of about 250 kWh• th and abovethanks to modular construction, all capacity stages are possible•

Digestates - separationseparation by screw press separator• drying solid stage with DS content of about 25% - 35%• specifically for applications where less than 50% of the waste heat is available•

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STELA - Digestate belt dryer

1 = feeding station2 = mixing screw3 = back mixing screw4 = heat exchanger5 = discharge screw

Digestate - back mixing processno separation necessary • drying to DS content of > 6% possible• back mixing of fluid digestates with already dried substrate by back mixing unit• high quality fertilizer granulate as end product•

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Dryer for Agricultural Products

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drying technology

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STELA - Technologically advanced drying

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Proven technology, creative solutions, flexible production! Small or really high capacities; with or without dust separation, continuous-mixed-flow or circulating batch dryer; gas, oil, steam or special heating – STELA is the right partner for everything! We develop the suitable solution also for extraordinary space constraints! There are more than 2.500

stationary STELA dryers all over the world. Our many years of experience were integrated into our new developments like the advanced technology of energy recovery, or the complete automation of the drying process with EQtronic, which provides enormous energy and cost savings.

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Drying principle

The drying product is conducted through the dryer by gravity from above to below. The vertical production surfaces are burred by horizontally arranged heat and exhaust ducts. The optimised roof form of these channels guarantees uniform settling of the product. The entire length of the roof ducts are open on the bottom.

The hot air flows over the front of the hot air ducts into the columns and then flows through the product batch. This heats the product and passes its moisture on to the circulat-ing air to dry it. The opposing flow cools down the air and is saturated until the product-dependent saturation limit. The moist air is vented through the adjacent exhaust roof duct. This air is suctioned out of the dryer by the exhaust fan. The constructive design of the roof ducts guarantees an optimal and consistent drying result with the utmost care for your product.

Advantages at a glanceuse 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•

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Construction

There are a multitude of variants for the design of your drying plant, which are assembled individually. According to your wishes, you will receive an optimum design for your application with the suitable components. The following examples will demonstrate to you some options which can be realized.

Design with centro-separator

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 large-scale 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.

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Design with circulating air

Not only the exhaust air from the cooling zone, but also the exhaust air (and thus the contained energy) from the lower dryer elements is recovered by means of a circulating air fan (10). A pneumatic discharge slide (4) brings about short discharge cycles. By means of pneumatic air flaps (dust separation flaps) (13), installed on the pressure side of the exhaust air fans (12), the air flow is interrupted during this discharge cycle. The same result is accomplished by the pneumatic air flaps (11) installed on the pressure side of the circulating air fan (10). 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.11

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Direct air heaterSTELA direct air heaters are used for firing oil or gas fuels. They are applied for heating up the air for STELA dryers as well as for other industrial products, for example in the brick making industry.

Hot air generation with direct air heaterThe direct air heater consists of an outer shell, an intermediate shell against radiation losses and a perforated combustion chamber made of highly heat-resistant steel, which is placed centrically in the shell. The hot exhaust gases are mixed with the fresh air heated along the wall of the combustion chamber and hot air of a homogeneous temperature is produced. Thus the energy of combustion is directly led into the dryer. The firing efficiency is 100%.

Hot air generation - direct air heaters

Oil or gas burnersWe only use quality burners of the leading European manu-facturers for generating hot air with fan burners. These prod-ucts are solely burners which guarantee low emission values and permanent, safe operation.

Depending on the heating medium and the requirements re-garding control behaviour, various designs are available:• digital multi-stage burners• light and heavy fuel oil• natural gas, liquid gas, biodiesel or biogas• design with exhaust gas reduction (Low-Nox design)

Oil Burner Monarch® WM-G20Oil Burner Monarch® WM-L20

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Indirect air heaterSTELA indirect air heaters are applied in processes where mixing of the flue gas with the air to be heated up is unde-sirable, e. g. when drying breadstuffs with fuel oil. STELA indirect air heaters are certified by TÜV (German Technical Control Board) and have a efficiency over 90% with outlet temperatures up to 120°C.

Hot air generation with indirect air heater The indirect air heater consists of an outer casing, an inter-mediate casing against radiation losses, flue gas passes and a closed combustion chamber made of highly heat-resistant steel, which is arranged centrically in the casing. Here the heating energy is transmitted to the fresh air only via the heat exchanger surfaces of the closed combustion chamber and the flue gas passes. The cooled combustion gases are drawn off into the open air via a chimney. Thus the hot air is completely free of flue gases.

Hot air generation - indirect air heaters

NP/RG AIRFLO® Gas line burners

Gas line burners for direct air heatingOften gas line burners are used as an alternative for direct air heaters. The burner is mounted into a heating duct, which is integrated into the hot air cap.

for natural or liquid gas• control range up to 25:1• firing efficiency 100%• ideal air mixing and thus consistent hot air temperature• space saving• no upper limit to capacity• no combustion fan required• robust and low-maintenance•

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Drying and cooling elements

Our drying and cooling elements are completely made of high-quality aluminum. The requested dryer capacity deter-mines the number of the required elements. If necessary, several element columns can be placed side by side. STELA offers a multitude of element sizes in order to consider con-structional specifications, especially for inside installations. Depending on the product, the plants are optimized for roof geometries, product bags for light products etc. - STELA focuses their expertise on your project.

waste heat recovery• careful drying process• pre-heating of the intake air to save energy • during hot air generationheat exchangers made of copper-aluminium • with galvanized frame

Hot water heat exchangerTo reach the drying temperature level, direct air heaters, heat exchangers and gas line burners can be applied singly or combined.

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The fans provide air movement within the product column. Depending upon the requirements, radial or axial fans are used. At the same motor output, the axial fan achieves a higher volume flow but at the same time, with only a mini-mal overall pressure increase compared to the radial fan.

radial fanvolume flows of up to 160.000 m³/hstatic pressure difference up to 3.000 Pa

balanced air wheel

Fan and air system

high efficiency• wheel statically and dynamically balanced• inlet through aerodynamically optimized nozzle • direct or indirect V-belt drive, motor types • corresponding to protection class IP 54 according to DIN 40.050.drive through low-maintenance three phase motor • 4, 6 or 8 pole star / delta start from 5.5 kWradial fan casing and base frame made of galvanised • steel sheetstandard channel flange frames•

axial fanvolume flows of up to 330.000 m³/hstatic pressure difference up to 1.300 Pa

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Dust separation systems

We all are very concerned about our environment. Legal limits and local regulations require the most modern dust separation systems.

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The STELA centro-separatorLatest state of the art• especially for maize fluffs and grain dust• Depending on the product, residual dust content is far less than the restrictions according set by BimSchG • (Technical Instructions on Air Quality)

The STELA centro-separator works according to the principle of a multi-stage centrifugal separator. A radial fan suctions the dust-laden exhaust air out of the dryer and forces it into the vortex chamber (1). There it is set in rotary motion. Due to cen-trifugal forces, the dust particles move towards the wall of the vortex chamber. Along with a small side stream of air, the dust particles are diverted by a tongue flap in the outermost part of the vortex into the secondary cyclone separator (2). A cylindrical lamellar system (3) reverses the direction of the main air stream as it leaves the vortex chamber. This causes any remaining dust particles to be thrown outwards and separated. The cone (5) of the secondary cyclone is bent 90°; here the dust is dis-charged. The purified secondary air stream is fed back into the main air stream through the central tube (4).

For direct dust sacking, a sacking muff is provided at the cone. For transporting the dust, the dust discharge is depressurized by means of a rotary valve.

Dust separation systems

dust-laden air purified air dust

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Dust reduction with pneumatic flap control

Pneumatic exhaust air flapThe pneumatic exhaust air flap closes before the material discharge begins, to prevent dust discharge due to move-ment in the grain column.

causes a lower power connection value for the entire plant• especially for maize drying with air recirculation in one sin-• gle operating cycle

With this simple but effective system, the intelligent PLC control shields the exhaust air and circulating air flow during product discharge by means of pneumatic flaps.

Pneumatic STELA twin dischargeThe STELA twin discharge is a twofold pneumatic discharge. It allows higher depths of the roofs and thus still more com-pact structural shapes and higher air saturation. Large quan-tities are discharged in short, abrupt intervals. The function corresponds to that of a multiple slide, which locks or opens the space between the roofs. An adjustment to various grain sizes from outside is possible without any problems.

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Projects worldwide

GermanyMDB-TN 1/7-SCapacity:5,7 t/h 35% -> 15%(maize)

Czech RepublicMDB-XN 1/6Capacity:23 t/h 19% -> 15% (wheat)7 t/h 35% -> 15% (maize)

GermanyMDB-XN 1/10Capacity:38 t/h 19% -> 15% (wheat)12 t/h 35% -> 15% (maize)

Czech RepublicMDB-XN 1/6-SCapacity:10,5 t/h 25% -> 15%(maize)23,1 t/h 19% -> 15%(wheat)

UkraineMDB-XN 2/13Capacity:45 t/h 25% -> 15% (maize)

EstoniaGDB-TN 1/4Capacity:14 t/h 19% -> 15% (wheat)

AustriaMDB-TN 1/3Capacity:10 t/h 19% -> 15% (wheat)4 t/h 25% -> 15% (maize)

Czech RepublicMDB-XN 2/6Capacity:45 t/h 19% -> 15% (wheat)14 t/h 35% -> 15% (maize)

HungaryMDB-XN 2/13Capacity:45 t/h 25% -> 15 %(maize)

GermanyMDB-TN 4/16Capacity:50 t/h 33% -> 15% (maize)

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GermanyMDB-TN 2/14Capacity:100 t/h 19% -> 15% (wheat)25 t/h 35% -> 15% (maize)

RomaniaMDB-TN 1/5Capacity:17,5 t/h 19% -> 15% (wheat)6 t/h 25% -> 15% (maize)

Czech RepublicMDB-XN 1/13Capacity:16 t/h 35% -> 15% (maize)

CroatiaMDB-XN 1/6Capacity:25 t/h 19% -> 15% (wheat)11 t/h 25% -> 15% (maize)

Czech RepublicMDB-XN 1/11Capacity:13 t/h 35% -> 15% (maize)

CroatiaMDB-TN 1/11Capacity:35 t/h 19% -> 15% (wheat)14 t/h 25% -> 15% (maize)

Slovakia MDB-TN 1/8Capacity:25 t/h 19% -> 15%(wheat)

Czech RepublicGDB-TN 2/6Capacity:40 t/h 19% -> 15% (wheat)10 t/h 35% -> 15% (maize)

Czech RepublicMDB-TN 3/12Capacity:112,5 t/h 19% -> 15% (wheat)45 t/h 30% -> 15% (maize)

SerbiaMDB-XN 1/15Capacity:25 t/h 25% -> 15% (maize)

Projects worldwide

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Projects worldwide

HungaryMDB-XN 2/10-SU Capacity:69,3 t/h 19% -> 15%(wheat)35 t/h 25% -> 15%(maize)

Czech RepublicMDB-XN 1/7-SCapacity:24,5 t/h 18% -> 14%(wheat)10 t/h 30% -> 14%(maize)

GermanyMDB-TN 1/7-S Capacity:5,5 t/h 35% -> 15%(maize)

HungaryMDB-XN 1/12-SUCapacity:6,9 t/h 35% -> 15%(maize)22 t/h 19% -> 15%(wheat)

Slovenia MDB-XN 1/8-SUCapacity:15 t/h 35% -> 15%(maize)10 t/h 19% -> 15%(wheat)

Czech Republic MDB-XN 1/13-SU Capacity:15,6 t/h 35% -> 15%(maize)

Hungary MDB-XN 1/13-SUCapacity:60 t/h 19% -> 13%(maize)

HungaryMDB-TN 1/8-SUCapacity:10 t/h 25% -> 15%(maize)

Czech RepublicGDB-XN 1/10-S Capacity:27,5 t/h 12% -> 8%(rapeseed)

Czech RepublicMDB-TN 1/6-SCapacity:16,5 t/h 19% -> 15%(wheat)5,1 t/h 35% -> 15%(maize)

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STELA – Mobile continuous-mixed-flow dryer Universal

ready... ... steady ... ... GO !

Drying principleThe make Universal is a roof dryer and operates with the suction method; it can be used as a continuous-mixed-flow or cir-culating batch dryer. Switching between both operating principles is simple and enables drying to be easily started up and shut down. The dryer is filled through the large feeding hopper and a high performance elevator. Gravity carries the material through the drying and cooling elements, which are burred with roof-shaped ducts. Hot air, heated by the air heater, flows through the hot air ducts and into the product. During drying, moisture transfers from the product to the air. The moisture-laden air is exhausted through the exhaust air ducts. In order to recover the heat, the heated air of the cooling zone is mixed in with the hot air flow. The dry, cooled material is transported by the elevator up to the discharge tube, which is located on top of the dryer roof.

The pneumatic discharge guarantees optimum free-flowing characteristics even with extremely moist maize. Full mobility in transport position according to StVZO (Road Transport Permit Act). Even the bigger dryers Universal 30 and 35 are installed within a few days. The high product discharge makes it easier to convey the dried product. Heat recovery to achieve low energy consumption as well as perfect dust reduction - the Universal meets all requirements!

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all components on one chassis• ready for operation in the shortest time• compact, space-saving design• plug-in delivery as per latest VDE standards (German As-• sociation of Electrotechnical Engineers)energy saving by heat recovery• minimal installation cost by pre-installation in our factory• simple and safe operation by PLC•

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Mobile circulating batch dryer

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The mobile circulating batch dryer type MUF is fed by means of the spacious feeding hopper and the powerful elevator. The space between the hot air duct (1) and the outer case of the dryer is filled completely with the product (2). When the dryer is started, all drives such as elevator (circulating system), radial fan and burner start in locked sequence. The air heated by the air heater is forced into the internal hot air duct (1) and flows through the product in the drying container (2). The built-in pressure-reducing roofs (4) ensure uniform distribution of force. The discharge mechanism (5) picks the product up in intervals and carries it through the elevator (6) into the upper part of the drying container. This upper, non-ventilated area serves as resting and tempering zone (“dryeration”). The MUF 110 also has a tempering vessel in addition to a resting zone above the drying ducts; here, the hot product is stored and can rest without ventilation. The product is discharged from the bottom of the drying tank by the discharge rollers (5) and transported upwards. The dis-charge rollers on the MUF 110 are split in length and run computer-controlled at different times. This guarantees a uniform mixing and distribution of the product into different zones.

The MULTI-THERM automatic system controls the tempera-ture of the hot air. This system works at high hot air tempera-ture at the beginning and switches in stages to a low tem-perature level for final drying. This procedure brings about a high energy efficiency and, at the same time, treats your product carefully. Having reached the desired final moisture (easy sampling), the dryer automatically switches to cooling. The product cools down to storage temperature and is dis-charged via the circular elevator.

1 = heated air2 = product / drying container3 = exhaust air4 = pressure reducing roof5 = roller discharge6 = elevator

STELA – Mobile circulating batch dryer MUF 45 / 70 / 110

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STELA – Mobile circulating batch dryer MUF 45 / 70 / 110

dryer system in high-quality aluminum• self-cleaning perforated plates for optimum • product ventilationcompact construction• pre-assembled, ready to plug in and operate• PLC control and electrical installation as per latest VDE • standards (Association of German Electrotechnical Engi-neers)no combustion fan required• quick change of location• automatic multi-stage temperature system • type Multi-Thermthus, optimum utilization of energy and low • energy consumptionexcellent drying result with most careful • product treatmentnew air heater technology with MUF 110• separation into rest and drying zones (“dryeration”) with • MUF 110 Tempering and drying in one plant - an economical and careful drying process.

MUF 45

MUF 70

MUF 110

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Feed-and-turn dryer

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1 = air heater (here directly fired) 2 = oil / gas burner3 = hot air fan4 = feeding hopper for wet product5 = drying bottom6 = feed-and-turn unit – for transporting and mixing the product7 = cooling fan

STELA – Feed-and-turn dryer

With their broad expertise in the field of drying technology, STELA Laxhuber can offer a great number of individual solu-tions for the development of concepts for waste heat recov-ery – and solely only for biogas block heating stations.Especially for smaller and medium thermal capacities from 300 to 800 kW, the STELA feed-and-turn dryer GS/MS is more up-to-date than ever. By way of its robust design and technology proven in prac-tice over decades, this drying system can dry the most wide-ly varying products, ranging from agricultural products (e.g. pumpkin seed, bio products etc.) to wood chips for thermal utilization or for wood gasification.

This simple principle guarantees an almost maintenance- and hassle-free drying process.

The type HS represents a further development for non-stand-ard products. Here, the air is suctioned through the dryer bed from bottom to top within an enclosed case system. The ad-vantage is that even difficult products, e.g. finer grain sizes, can be dried. The air enters the hot water heat exchanger from the bottom and is suctioned diagonally through the bed. The fan exhausts this air at the discharge side. The feed-and-turn system conveys the product from feeding to dis-charge – both in continuous and in batch process.

GS / MS

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6

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1 = heat exchanger 2 = air cap3 = fan4 = feeding hopper for wet product5 = drying bottom6 = feed-and-turn unit – for transporting and mixing the product7 = dust separation with centro-separator8 = exhaust air

STELA – Feed-and-turn dryer

more than 1.500 dryers in operation• utilization of high quality aluminum• low investment costs• easy handling• universally applicable and very flexible for a • variety of products

energy-saving drying system• variable dumping heights from 40 up to 400 mm• also available in plug-in mobile construction• easily exchangeable web belt, thus optimum drying even • for fine products

HS

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Innovation

Competence

Reliability

Also in the future...

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drying technology

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STELA Laxhuber GmbH | Öttingerstr. 2 | D-84323 MassingTel. +(49) 08724/899-0 | E-Mail: [email protected] | www.stela.de

stela laxhuber-product overview

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