By farmers - for farmers

Hay Drying Systems by Heutrocknung SR

Why mechanical hay drying?

Drying hay by machine offers a wealth of advantages when compared with the conventional methods of hay production with its need to turn the hay frequently in the field. Our system allows you to benefit from the advantages of this technological progress in under-roof drying. It is important that both main components in our system (air dehumidifier and fan) are fitted with a PLC and that each has a frequency converter; this is why the system includes at least two frequency converters. We have set ourselves the goal of manufacturing just such systems for you, in harmony with our basic principles that our products have long-term benefit, are profitable, sustainable and natural.

What are the benefits?

  • Only 24 hours and the hay is brought in
  • You need only turn the hay twice more
  • The weather ceases to be a problem
  • Planning becomes less stressful
  • The harvesting process is speeded up by the high degree of efficiency and power
  • You can cut the fodder crop at the optimum time
  • You can take advantage of short periods of fine weather for hay-making
  • Your milk yield increases. In conventional drying by the sun the hay has to be turned frequently and this removes many nutrients (leaves break off, loss of crumbs), but these disadvantages disappear with machine drying
  • You prevent fungal contamination of the fodder and the still damp hay from drying out quickly

What happens to the food quality?

  • contains more nutrients in the hay
  • less supplementary feeding of concentrates
  • healthier animals - lower veterinarian costs
  • milk yield remains the same during winter feeding

The new 3rd generation and the efficiency factor

Among other considerations, the principles for modern, energy-efficient hay drying include the following factors:

  • There is an interior air flow cycle and roof extraction and also a combination of the two for the air flow.
  • The air flow is adjusted fully automatically (= fan with frequency converter) to the drying batches introduced, irrespective of the fill level and the drag of the hay.
  • The air humidity is adjusted fully automatically (= air dehumidifier with frequency converter), in order to obtain the highest elimination of water possible from our system.
  • The box sizes are compatible, irrespective of the drying batches required by the farmer.
  • The air mass flow management system and the cooling unit are fully automated and regulated by the HSR central control system. The regulated air volume per m2 (250-400 m3) is kept consistent at a frequency range of 35 to 60 Hz, which includes major energy savings, irrespective of the drag and filling of the hay to be dried.

Our third generation of hay drying systems has been designed and produced with exactly these factors in mind. The required operating point of the drying system is achieved by means of our fully automatic PLC central control system. Frequency converters are used to control the speed to ensure the best efficiency factor on the fan and the air dehumidifier. These are regulated by specialised software solutions in the central control system.

More than an air circuit

When selecting airflow management – interior airflow circulation or roof extraction – the higher temperature achieved every time is crucial. In order to attain the highest possible energy-efficiency, intelligent switching of the air flows is inevitable. The HSR central control system performs this function fully automatically and with the new shutters even without roof valves.

The sophisticated dehumidifier heat pump is put to optimal use when operating the system with the internal air circuit. Without air dehumidification, air humidity levels equalise, and the air does not become drier despite ventilation. When using hood extraction in the three-way system, the intelligent HSR central control decides whether the air from the hood extractor passes through the dehumidifier or is blown back into the haystack. This allows the system to work even more efficiently.

Apart from the reduction in relative humidity, the air is also warmed, which allows the hay to be dried to its final condition. The temperature increases as air passes repeatedly through the circuit. Yet another benefit of the central PLC control system is that the drying process can be displayed on a monitor.
This allows operators to determine clearly when the hay is completely dry. The HSR remote maintenance module even allows the process to be monitored via a smartphone or tablet!

Why choose Heutrocknung SR?

Choose mechanical drying technology from HSR Heutrocknung, the leaders in innovation. A high degree of efficiency and power for low energy consumption (up to 1.5 cents per kilogram of hay) is a particular feature of our drying systems. You, too, can become a hay expert with our patented air dehumidifier technology. True to our motto, "from the farmer to the farmer" we have designed and tested our systems on our own farm to make sure that they perform immaculately and we have already spent money on research and development, so that the customer is not burdened by such costs.

We support you from the first draft, through the planning stage and right up to the actual construction phase, in order to provide you with the optimum in drying systems. We provide targeted customer training to give you the important facts and useful information you need to assist you in getting the best out of your HSR drying system.

Whenever you require us, our many service partners throughout Europe and our firm's own construction and service team will arrive promptly at your farm to bring you any assistance, which may be needed.

10 good reasons for choosing modern technology from HSR:

  • Hay drying systems at the cutting edge of SR technology with testing facilities on our own agricultural hay farm
  • Low-loss preservation of the material to be dried
  • Low current consumption - our system can be connected to any power supply system
  • Evaporators with patented technology for a significantly better capacity than with earlier versions
  • For all sizes of farm - for loose hay, round bales, drying herbs or hops
  • Energy efficiency during the drying process due to forward-looking software solutions
  • All designs also available as compact systems - saves costs, simplifies installation, no need to construct a fan chamber
  • Individual design planning
  • Full support in planning and construction
  • Targeted customer training

Comparison: Dehumidifier air recirculation mode / pure heating mode (heater)

A heater must continuously draw in and heat outdoor air. Very humid outdoor air and 13°C outdoor air temperature or less are often the case. 15°C heating of the outside air to 28°C drying air requires 200 kW heating power with a heater for a 90 m² hay box (= 10m³/s ).

With a dehumidifier, there is no need to constantly heat up the outside air (heating power), for example by: 13°C to 28°C. The circulating air temperature of 28°C (or more) is built up once by the dehumidifier during the heating phase. The already humid and heated indoor air be reused by eliminating condensation only in the case of the dehumidifier.

Heated indoor air can therefore be circulated 20-40 times per hour. The condensation water is discharged cold and the heat it contains is returned to the air circuit. Depending on the design of the dehumidifier, the circulating air is increased by a further 7°C to 15°C. These are the decisive advantages of the dehumidifier in recirculation mode. Proper thermal insulation of the drying hall enhances the effect of the dehumidifier in recirculation mode.


Diagram of the heating power required to heat up the system

Required heating power

In a scientific study of the required heating power, Professor Wirleitner determined the required heating power to heat by 5°C, 7°C, 10°C and 15°C.

Image source: Prof. Dipl.-Ing. Gotthard Wirleitner

HSR is scientifically confirmed

A wide range of characteristics and the effectiveness of the HSR drying systems are continuously tested and scientifically confirmed under real conditions, through trial harvests in collaboration with the research institute Raumberg-Gumpenstein.

This reflects our standard for constant improvement and optimisation of our systems perfectly. Numerous findings and improvements were already possible stemming from this important research work, and there are more to come in the future.

More about this in our hay blog (partly in German):

Have we awakened your interest?

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Do you have any questions?

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