Projects of belt dryer
Projects of belt dryer
Learn more about our references in the field of sludge drying.
Sludge as a raw material
Sludge as a raw material
Dried sludge as a phosphorus and energy supplier
We recycle your sludge
We recycle your sludge
We’re happy to accept your sludge! Contact us.



With its compact design, the BURKHARDT DRYLINE® belt dryer is a byword for top performance, in terms of useability, efficiency, ease of maintenance and all-round service. Our tried-and-tested, practice-oriented process is a winner, creating four drying levels on just two drying belts to double the possible drying area. The BURKHARDT dosing head® streamlines sludge feeding – a plus in quality and safety. Our fully automated system control lets the system be operated without constant supervision whilst maintaining maximum drying output and is configured to suit your process. Users also benefit from the BURKHARDT FULL SERVICE, which offers the sludge drying system as a comprehensive turnkey package if requested.

BURKHARDT sludge drying process diagram:

BURKHARDT sludge drying belt dryer process diagram


2 belts + 4 levels = a clever solution to sludge drying!

Dewatered sludge passes the BURKHARDT DRYLINE®’s two drying belts, consisting of perforated powder-coated steel plates, successively. During this phase, hot air continuously flows through the sludge. In doing so, it passes slowly rotating and self-cleaning bar rollers. A stepped air recirculation system removes the water in the individual drying zones resulting in a uniform end product with similar sized grains.

The advantage is in the detail: The BURKHARDT DRYLINE®, although a two-belt dryer, has four drying levels, all thanks to its special belt construction. At the end of the first belt, the sludge is dropped onto the returning part of the belt on the level below. The same thing happens on belt two, with it, also being used twice. In this way, the space available inside the belt dryer is efficiently used to its maximum. The result is storable, sanitised biosolids ≥ 90% DR with excellent fuel properties.

The drying belt’s perforated plates ensure adequate ventilation and an efficient drying process.Efficient and optimised air flow is one of the main reasons behind the BURKHARDT DRYLINE®’s high effectiveness.Innovative, low-maintenance sludge dispensing head for even sludge distribution.

BURKHARDT Dosing Head® – innovative sludge feeding

Another innovation from BURKHARDT rounds off the drying process: a dosing head optimised for ease of maintenance that evenly distributes sludge directly onto the top belt of the belt dryer. This ensures efficient drying.

Exhaust air treatment – one step ahead

The DRYLINE®’s air recirculation system is designed for maximum use of air and moisture saturation. Using the air multiple times means you make the most of the energy thus saving energy. But the really great thing about the intelligent air recirculation system is that it reduces exhaust air. The exhaust air treatment downstream of the dryer ensures that limits required by law are complied with and can be adapted to individual needs. The innovative advance of a state-of-the-art, tailor-made exhaust air volumetric flow is good for both users and the environment.

System control 4.0

The system control developed by BURKHARDT controls the entire process line, from transporting wet sludge, to discharging the granulated end product, through air flow with exhaust air treatment, to heat generation and distribution. This establishes state-of-the-art process monitoring. Individual parameters can be set thanks to in-house programming. The BURKHARDT DRYLINE® digitises your production processes to perfection: all parameters, such as output, dry residue content, moisture, pressure and temperature, are recorded and visualised in a network-compatible process control system. Notification functions and visualisations on mobile devices make the system easier to operate. The drying system runs fully automated for 24 hours, with no on-site monitoring necessary. The BURKHARDT plant portal makes it possible to access system parameters anytime, anywhere.

We bring it full circle

BURKHARDT considers itself a practicioner among suppliers of sludge dryers. As a manufacturer and experienced operator, we only offer our customers technologies that have been tried and tested in the field. In addition to energy efficiency, ease of maintenance and user-friendliness are always key to system planning. Thanks to our DRYLINE®, sludge waste product is converted into sustainable, optimised fuel. With the BURKHARDT FULL SERVICE, all services relating to sludge drying are available both individually and as a comprehensive package.

Technical data

  • Two belt dryer with four sludge layers
  • Belt dryer length: 6 m to 36 m of effective drying length
  • Water evaporation capacity: up to 3,250 kg/h
  • Operation: 24/7 or > 8,000 h/a
  • Throughput capacity: up to 5,000 kg/h
  • Thermal energy requirement for drying: 0.85 - 0.95 kWth/kg water evaporation
  • Electrical energy requirement for drying: 0.010 - 0.100 kWel/kg water evaporation
  • Dry residue input/output (DR): 18 - 35% DR / 90% DR – the sludge can be checked in the test plant if values are outside the dry residue input range

Advantages at a glance:

  • Efficient use thanks to compact design - two belts, four layers
  • Process optimised by automatic matrice cleaning
  • Quick-change unit saves time when changing matrices
  • Less pressure lost in the sludge line with minimum bend radius of ± 30°
  • Additional pressure minimization in the sludge line due to short swivel arm hose
  • Creates a porous, granulated product with a defined diameter and high bulk density
  • Plus in terms of hygienisation due to even drying of the end product
  • Low-dust end product
  • Fully automatic as a result of digital system controls
  • Digital process monitoring incl. tailor-made exhaust air treatment
  • FULL SERVICE – services available individually and as a comprehensive package
  • BURKHARDT as operator and manufacturer – technology tried and tested in the field

The volume of sludge is reduced after drying in the BURKHARDT belt dryerDrying sludge makes it hygienically safe and reduces its odourDrying sludge raises its heating value to nearly that of lignite

Your contact for sludge drying:

Burkhardt news


Starting in autumn 2024, a new Burkhardt sludge drying plant will be built in Hall in Tyrol.


Since the 1st of January, an additional 32 wood gas plants have become part of the Burkhardt Group.


Power and heat generation for pellet production


A delegation from Japan visits Burkhardt's sites.


Topping-out ceremony and commissioning of the first wood gasification plants in Fürstenfeld


Best wishes for the Festive Season and a Happy New Year.


In 2023, we can look back on another eventful year in the fields of Power engineering and Sludge drying.


The assembly work in Michelstadt is largely complete.


Burkhardt partner Sanyo Trading visits Muehlhausen


On November 29th, the Biomass Gasification User Conference will take place in Innsbruck.


Burkhardt's largest construction site is currently a hive of activity.


Successful business expansion with a pellet plant and wood power generation by Burkhardt wood gasifier


At the end of August, two Burkhardt wood gasifiers V3.90S and a combined heat and power unit ECO 495 made their way to Switzerland. 


The groundbreaking ceremony for Austria's largest wood gasification plant took place on June 20, 2023 in Fürstenfeld with the project participants. 


Burkhardt's newest facilities in Austria are located in Hall in Tyrol at Gutmann GmbH.


The successful continuous operation of our own sludge drying plants convinces the customer!


 As one of the first in 2023, the new wood gasifier CHP plant was commissioned in Niederanven, Luxembourg.


Approaching market launch: BURKHARDT V5.90S woodchip gasifier


Best wishes for the Festive Season and a Happy New Year.


The year 2022 comes to an end.


Commissioning of the Burkhardt unit in Bolzano has been successfully completed.


Our V4.50 is going into operation in various countries as part of a European funding project.


The wood gas plants in Ladbergen/North Rhine-Westphalia have been running for more than 10 years


50 kW container unit in operation at University of Sheffield since February 2022


Burkhardt combined heat and power unit with an output of 390 kWel and 580 kWth.


Another turbulent year comes to an end.


Best wishes for the Festive Season and a Happy New Year.


Congratulations on more than 82,500 operating hours.


With the development of the Burkhardt V3.90S wood gasifier we have taken the next step towards higher levels of technical availability and customer service. The V3.90S wood gasifier is a further development of the well-known V3.90 and offers enhanced process control and unit design.


Despite the corona pandemic, we was able to commission six more plants with our partner Sanyo Trading in Japan. The special feature of this commissioning was the special implementation on site.


Official presentation of the Burkhardt wood gasifier and the combined heat and power unit of the Horb Weststadt heating station


In its fourth edition, Bioenergy International reports on the repowering with Burkhardt wood gasifiers at Biomassehof Achental in Bavaria, Germany.


Read the Policy Brief of Bioenergy Europe about the highlights of their Statistical Report 2019, focusing on pellets.


The interested parties met in the mid-October at the Murau-Stolzalpe heating plant in Austria for an exchange of experience.


Delegation visits Burkhardt production facilities in Mühlhausen.


Expansion of the existing biomass power plant for cogeneration of heat and electricity in Grassau


The first Burkhardt wood V4.50 gasifier in Austria is in operation.


Eleven further wood gasifiers and cogeneration units have started operation in Japan.


From the 27th to the 31st May 2019, Burkhardt GmbH was present at LIGNA in Hanover with a company stand.


Mobile energy generation unit for V4.50 wood gasifier and CHP smartblock 50T sets out on its travels


A wood gasifier V4.50 of the manufacturer Burkhardt GmbH from Mühlhausen (Bavaria) set off on its journey to Austria.


The right addition found for summer operation


Successful commissioning of Burkhardt wood gasifiers at the heat plant Murau-Stolzalpe.


Successful commissioning at the Möbelfabrik Muotathal shortly before the year-end


In its 38th edition, the “Holz-Zentralblatt” magazine reports on the newly constructed pellet works and the production of green energy using Burkhardt cogeneration systems.


Two new Burkhardt plants have commenced operation in Luxembourg.


The completed CHP is tested on the factory test stand.


In a practical evaluation report, the Bioenergy Atlas of the Austrian Biomass Association provides information on the new Bad Bleiberg biomass heating plant, which commenced operation in 2018.


In cooperation with our Japanese partner Sanyo Trading, we created an interesting video of the Burkhardt cogeneration plants in the Far East …


The district heating station Murau-Stolzalpe will be expand with three pellet wood gasifier CHP plants from Burkhardt.


A wood gasifier-CHP-plant from Burkhardt went in operation at the foot of the Mount Fuji.


The magazine Bioenergy International reports about the first wood gasifier and CHP in Japan.