Clean energy from biowaste

We use municipal biowaste to generate biogas

Potato peelings, garden leaves, food leftovers – everything we put in the organic waste bin can be turned into green energy in future. Working with state-of-the-art biowaste anaerobic digestion plants, we convert this waste into environmentally friendly biomethane. This can be used to generate electricity, and heat, in the transport sector and in industrial processes. The residues remaining once the waste has been digested can be reused as valuable compost in gardens and in agriculture. Unlike traditional biowaste composting, biogas generation uses the energy stored in the waste and reduces emissions of methane and carbon dioxide.

Our plant in Dresden-Klotzsche processes around 46,500 tonnes of biowaste a year. We are currently building a further plant with a capacity of around 33,000 tonnes a year in Bernburg/Saale in Saxony-Anhalt, and we are planning further biowaste anaerobic digestion projects across the whole of Germany.

How does biowaste digestion work?

Overview of process steps

 

  1. Delivery
  2. Preliminary treatment
  3. Digestion in digester
  4. Biogas processing and feeding into natural gas grid
  5. Treatment of digestion residues

Delivery

  • Fully enclosed delivery area
  • No odour emissions
  • Supervision and control of organic waste deliveries

Unwanted substances are screened out, e.g.

  • Stones, glass and plastics are screened out
  • Metal is separated
  • Plastic sheeting is mechanically removed

Digestion

  • Conveyor belts transport the waste into the digester
  • Bacteria decompose the organic waste
  • Decomposition takes place in the absence of oxygen
  • Stirrers keep the mass in motion
  • The resultant raw biogas rises upwards and is captured

Biogas processing

  • Processing of raw biogas through separation of CO2
  • Biogas reaches natural gas quality
  • Gas is fed into the public natural gas grid

Treatment of ferment residues

  • Digestion residues prepared for use in agriculture
  • High-quality compost and liquid digestion products
  • Certification within RAL quality assurance scheme

Input and Output

Biowaste digestion in an energy context

Biowaste materials flow

We use municipal biowaste to generate biogas.​​
Potato peelings, garden leaves, food leftovers, coffee filters – everything we put in the organic waste bin can be turned into green energy in future.

The contents matter! 
For the valuable energy resources available in municipal organic waste to be usable, it is crucial that consumers put the right waste in the organic waste bin. 

 

What we need in biowaste: What we do not want in biowaste:
Waste vegetables and fruit​​Plastic (including non-compostable plastic bags)
Eggshells​Packaged food
Solid food leftoversCoffee capsules
Coffee filters and teabagsCrown caps/corks
Kitchen roll and paper towelsNappies
Tree and shrub cuttingsSanitary articles
Leaves and grass cuttingsGlass
Potted and balcony plants with soilStones
Weeds​Cat litter
Wilted flowersWood scraps
 Ash from fires

Composting:

Biowaste digestion

Uses oxygen from the air

Oxygen is excluded

Only produces compost

Produces compost and biogas

Key problems are greenhouse gas emissions and odour

Generates compost of comparable quality

 

Full enclosure prevents odour emissions

 

The biomethane generated at an biowaste anaerobic digestion plant can be used in a variety of ways:

 

  • Decentralised heat and electricity production​​
    Highly efficient use of biomethane in CHP plants with corresponding heat demand

     
  • Transportation
    Use at CNG filling stations; uses include trucks, waste vehicles and local public transport

     
  • Industry and commerce​​
    Use as green gas

CO2 savings due to organic waste digestion with gas processing:

Compared with composting approx. 7,400 tonnes p.a.*​​

That is equivalent to supplying
approx. 2,200 households with green electricity and ​
approx. 300 households with green heat each year

* Assumption: digestion plant with capacity to treat 33,000 tonnes of municipal organic waste each year.

Biowaste digestion: the specifics

Questions and answers

… How does my local authority gain?

Going forward, in a highly efficient and climate-compatible process the plant will make use of biowaste. This kind of plant boosts the region as a place for innovation and investment and also generates additional trade tax revenues. With their biowaste bins, local citizens automatically become part of the energy revolution. Biowaste is permanently available and is produced every day in any event. That means that bio-natural gas from biowaste is a stable and reliable form of renewable energy that can replace fossil-based natural gas. In short: energy from your region for your region.

… How safe is it?

The plant will be built to the latest technological standards and is approved and operated in line with the strict requirements of the Federal Emission Protection Act and regularly checked by experts.

… Are you sure it does not smell?

Yes. The plant is odour-proof. A high-performance extraction process cleans both the waste acceptance area and all the hall air. All extracted air is cleaned in a modern biological filter. This technology is robust and proven. It ensures that the plant does not emit any unpleasant odours. We go beyond legal standards in this respect. 

… Is it noisy?

The plant operates quietly at less than 40 decibels. That means even the local traffic is louder. Operations are therefore not expected to create any noise problem.

Benefits for local authorities and municipality where plant is located

Benefits for local authorities

  • Legally compliant disposal solution
  • Sustainable use for contents of biowaste bins
  • New business with positive contribution to the energy revolution

Benefits for municipality where plant is located:

  • Jobs
  • Trade tax revenues
  • Active contribution by municipality to the energy revolution

Our reference projects

Biowaste anaerobic digestion plant in Dresden

This plant, where operations began in 2017, has been part of our group of companies since 2018.
It processes 46,500 tonnes of organic waste a year.

more information

Biowaste anaerobic digestion plant in Bernburg

In Bernburg (Saxony-Anhalt), the commissioning of a state-of-the-art plant is currently taking place, which can process about 33,000 tonnes of biowaste per year from Bernburg and the surrounding area and produce about 21,000 MWh of biomethane. This will avoid emissions harmful to the climate and save around 7,400 tonnes of CO2 a year.

more information

Biowaste anaerobic digestion plant in Sinsheim

Since autumn 2019, this plant has used around 60,000 tonnes of biowaste a year to generate around 40 million kilowatt-hours of biogas and valuable quality-assured dry compost. The raw gas is treated at a proprietary plant and fed into MVV’s regional natural gas grid.

MVV holds a 41.5% stake in the company responsible for the plant, AVR BioGas GmbH. As a competent and experienced partner, MVV contributes its expertise in biogas treatment and grid feed-in processes to the project.

more information

Contact

Dr. Christian Hower-Knobloch
Geschäftsführer MVV Umwelt GmbH

Contact

Uwe Zickert
Managing Director of MVV Umwelt GmbH