The defibrator: energy from waste



Optimized gas yield thanks to efficiently defibered substrates

The Biogrinder (RBG) is mostly used in biogas production for the intensive mechanical processing of organic raw materials before fermentation. Impact and shear forces optimally crush and defiber the input material, accelerating gas production and making the overall process more stable. It also greatly expands the selection of raw materials. As a result, the entire biogas plant operates much more economically and efficiently. 

Benefits at a glance

  • Accelerated gas generation
  • High energy efficiency
  • Stable fermentation process
  • Continuous process
  • Future-proof investment

BHS Biogrinder crushes and mashes organic domestic waste

BHS Biogrinder - Aus Biomüll wird Biogas DE.mp4

BHS Biogrinder crushes and mashes organic domestic waste

The BHS Biogrinder (type RBG) is used in the processing of biomass for biogas generation. The BHS Biogrinder is in use in southern Germany to crush and mash organic domestic waste. The upstream substrate processing speeds up gas production in the fermenter. Overall, the biogas plant operates more efficiently and reliably.

One machine - a thousand raw materials.

Fermenter-friendly processing

  • Enhanced uptake of nutrients for micro-organisms through intensive defibration, shredding, and homogenization of the input material
  • Particularly effective in the case of highly fibrous biomass
  • Extraneous materials, such as soil clods and stones, are also crushed

Greater variety of raw materials

  • Raw materials that were previously difficult or impossible to decompose in the fermenter can now be processed with ease after processing in the Biogrinder.
  • Wide range of applications: Corn silage, grass clippings, green/organic/animal waste, sugar beets, straw of all kinds

High energy efficiency

  • Very short substrate retention times
  • Nearly all the energy applied is converted into crushing capacity and not heat
  • Further energy savings result from the reduced need for chopping during harvesting, reduced agitator use in the fermenter

Stable fermentation process

  • Homogenization facilitates transport of substrates
  • No deposits build up in the fermenter

Continuous process

  • Continuous operation simplifies technical integration of the machine into the overall plant
  • Optimal throughput rate since the motor output of the Biogrinder is adapted to the plant

Maintenance-friendly system: child’s play thanks to disc rotor

  • Only one person needed thanks to user-friendly design
  • No additional lifting equipment required due to the moderate weight of all components (≤ 20 kg)
  • Fast replacement of wear parts such as the rotor and wear parts of the housing, maintenance opening in the inlet
  • No special tools required

Future-proof investment

  • High degree of flexibility in the selection of raw materials in view of changing market conditions and legal frameworks


Feed opening

The Biogrinder has a large feed opening, which allows the machine to be easily fed with different materials.


The rotor is mounted on a vertical shaft. The material stream first connects with a distribution cone. Below this, the rotor has two levels, each of which can be fitted with a maximum of two pivot-mounted hammers. Crushing is carried out primarily between the rotating hammers and the stator strips on the machine casing. The arrangement of the hammers is variable, so that the rotor can be optimally configured for the specific task.

Distribution cones

The distribution cone feeds the inserted material to the hammer levels. This prevents possible clogging of moist or light material in the feed area.


 The carbide hammers welded onto the base are optimized to deliver a long service life. Due to the flexible bearing, even extraneous solid materials, such as stones and soil clods, can be crushed easily. Modification of the hammer configuration can be achieved in minutes.

Stator bars

The stator strips and wearing plates are fastened from the outside by means of bolts. The wearing parts can thus be easily exchanged and are optimized for long service life.

Discharge opening

The treated substrate continuously exits the processing chamber through a generously dimensioned discharge opening. A liner consisting of plastic plates prevents caking.


Depending on the size, required throughput and desired crushing ratio, the Biogrinder is equipped with motors ranging from 37 to 90 kW.

Maintenance hatch

The Biogrinder has a large access hatch at the top to facilitate easy and quick maintenance or retooling.

Vibration damper

The machine is installed on vibration dampers to prevent the transmission of vibrations into the surrounding steel or concrete construction.


Designed as a technically reliable solution, the Biogrinder has a recirculating oil lubrication unit. This system is also used for cooling the bearings.

Key transfer system

In order to prevent uncontrolled access via the maintenance hatch, the machine is equipped with a key transfer system. The power supply is interrupted and the machine can be opened only by means of a special key after the rotor has come to a standstill.

Control unit

The Biogrinder can optionally be equipped with a control system. In the case of frequently changing input materials, it makes sense to implement a frequency inverter. In combination with the variable rotor configuration options, this allows for optimal coordination of the desired targets in terms of crushing results, throughput rate and power consumption.

Steel structure

As an option, customers can order a standardized steel structure for installation of the machine. It features a maintenance platform for the Biogrinder and a ladder.


Gain the technical edge

Gain the technical edge

1 | Disk rotor  Due to the concial shape of the disc rotor, the input materials are transported without energy loss directly in the area of the defibering process in front of the hammer. The special design of the disk rotor reduces wear costs and makes it easy to maintain. The main body of the disk rotor remains in the machine and the rotor components can be replaced individually or in groups based on the degree of wear.

2 | Stator bar  The stator bars make it possible to defiber the input material to the smallest degree possible, which accelerates biogas production. Different numbers of stator bars can also be deployed in variable positions to give materials with a wide range of properties the best possible preparation before they enter process later down the line.

3 | Hammer  Different hammer shapes and metal alloys are available to provide you with the highest degree of processing for your input material. You can select the right tool depending on the type of input material..

4 | Defibering  Conventional processes for defibering the input material only moderately increase the working surface for the bacteria in the fermenter. In contrast, the Biogrinder expands the working surface many times over. This allows the retention time in the fermenter to be reduced by a factor of two to ten, depending on the material. One positive side effect of the material degrading faster in the fermenter is that a homogenous cake forms. This means that less stirring is required, which results in significant energy savings.

Technical specifications

Performance data
TYPERotor DiameterMotor
RBG 081.000 mm55 kW / 90 kW
Dimensions and weights
RBG 08510 mm750 mm260 mm780 mm1.640 mm2.450 mm1.280 mm2.010 mm3.000 kg

1) Depending on the feed characteristics, data may differ from the information provided.

Technical specifications of customized models may differ from the data provided here. All technical specifications are subject to change due to continuous development. Subject to change without notice. 

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Two biogrinders for an organic waste plant in China

November 2022
In China, BHS-Sonthofen is already widely known as a reliable partner for recycling technology. Good word of mouth convinced the operator of a waste recycling plant in Xi’an, Shaanxi Province in northwest China to order two biogrinders for the recycling of kitchen waste. The treated organic material mainly consists of the food waste from homes and restaurants. Some adjustments to meet the specific requirements of the project led to an improved efficiency of the BHS technology with increased biogas production and better process stability.

Crushed it: Transforming waste into energy with the BHS Biogrinder

February 2022
Green energy is not all the same: Indian company Mithras Green Technology uses the Biogrinder of type RBG 08 from BHS-Sonthofen to produce sustainable energy solutions from organic municipal waste. Now the company not only saves valuable resources, but also a lot of time.

An environmentally friendly alternative to peat: The Biogrinder efficiently processes compost

February 2021
The Biogrinder from BHS-Sonthofen is successfully used by a cooperative in northern Germany for the production of an alternative to peat. A mobile plant with a control system from BHS Control Systems was implemented. The plant efficiently shreds surpluses of compost material and produces a substance that is suitable for use as an environmentally friendly alternative to peat. For example, the product is added to the production of potting soil to reduce the amount of peat contained in it.

First Biogrinder for India's biogas industry

December 2019
India generates a large amount of agricultural waste, including crop residues. As burning organic waste is considered to be a major cause of air pollution, the government of India has been offering incentives to mitigate the pollution problem and convert rice straw that is widely available in India into biogas. “Especially in northern part of India, rice straw will be an important raw material for biogas production”, says Neelesh Desai, Managing Director of BHS-Sonthofen India.

Biogrinder for biomass treatment plant

May 2019
The Association for Waste Management Kempten put a biomass treatment plant into operation in 2019. Technology worth about €2.8 million in total ensures that foreign matter is optimally removed from organic waste and green waste to prepare it for fermentation. A BHS-Sonthofen Biogrinder is now used to process and shred this material. Its low power consumption and exceptional shredding results, even for challenging input material, are what make it stand out.

Technical articles in the media

BHS-Sonthofen contributed to biomass projects in the Phillipines

February 2022

USA-based Dole Inc. generates large amounts of pineapple waste, which the company uses to produce biogas in the Philippines.
Dole is looking to generate nearly eight MW of power per year at the two plants, Surallah and Polomolok, German company BHS-Sonthofen reported this year. To achieve this goal, the plants deploy Biogrinders from BHS to efficiently process substrate.


Efficiency in biogas generation

October 2020

BHS-Sonthofen has launched a new, completely redesigned version of the succesful Biogrinder on the market. The Biogrinder is used in biomass processing, where it ensures that biogas is generated efficiently and production is accelerated. The machine is now fitted with a disk rotor and stainless-steel components, making it stand out thanks to its improved durability and flexibility.

recovery 05-2020

ICBR 2024 - International Congress for Battery Recycling

09/10/2024 - 09/12/2024 | Basel (Switzerland)

IFAT India 2024

10/17/2024 - 10/19/2024 | Delhi (India)
Germany, Austria, Switzerland

MEBA Biogas GmbH
Emil-Eigner-Straße 1
86720 Nördlingen

+49 9081 27214-00

Your contact:

Karl-Heinz Bachmann
 (Managing Director)

+49 9081 27214-14
+49 171 771 3330 (mobile)


Lobe ApS
Fabriksvej 15
6580 Vamdrup

Your contact:
Ejner Iversen
(Managing Director)

+45 76 84 34 84
+45 50 41 28 40 (mobile)
Italy & Spain

Via Aurelia, 1100
00166 Rome

Your contact:

Dr. Cristiano Caponetto
(Sales Director)

+393356234638 (mobile)

Your contact:
Liu Chen
(Business & Sales Manager | Recycling & Waste Process)

+86 22 82126263
+86 133 0139 2393 (mobile)

BHS-Sonthofen (India) Pvt. Ltd.
6-3 252/1/7/B, 3rd floor, Prakash Lights Building
Erramanzil/Banjara Hills
Hyderabad 500 034

Your contact:
Himanshu Mavadiya
(Sales Engineer)
+91 40 23315341 / 45
+91 93 93 18 3939 (mobile)
Global sales contact

BHS-Sonthofen GmbH
 - Sales Recycling Technology -
+49 8321 6099-520

Your contact:
Reinhold Jäger
(Sales Manager | Recycling Technology)
+49 8321 6099-172
+49 176 10083545 (mobile)