Database of Waste Management Technologies Life

Case Study 19 – Mechanical Biological Treatment (MBT) with wet AD

 

General Information Photo Gallery
Name: Lübeck MBT case study 19

Lübeck MBT

case study 19

Lübeck MBT

case study 19

Anaerobic digestion and air filtration components of the plant

Owner: Waste Company of Lübeck
Operator: Haase
Technology: MBT-Wet AD
Designed Capacity: 150,000 tpa
Cost: € 30 million (capital cost)
Location: Lübeck, Germany
Served Area: -
Commercial Start Up: 2007
Contact Details
Address: Haase
Spreestrasse 3 24539
Neumuenster,
Germany
Phone Number: +49 4321 2675-0
Fax: -
Email: info@haase-ec.de
Website: haase-ec.de

 

Short Description

The Lübeck Waste Treatment Facility is a mechanical biological treatment plant located near the city of Lübeck in Germany. The facility treats the entire municipality's waste stream utilising a municipal waste treatment process consisting of mechanical sorting and anaerobic digestion. The facility has the ability to process up to 150,000 tpa of mixed waste. This facility was constructed in 2005 at Luebeck-Niemark and utilises the Haase MBT+WAD process.

The waste treatment facility also includes a separate composting facility for green waste.

The first component of the process recovers metals and recyclable elements from the incoming waste. It also produces a refuse-derived fuel which is sent to a dedicated combustion facility to supply domestic heat and electricity to the town of Neumünster

The system design at Lubeck has been the inspiration for three facilities planned for construction by Viridor as part of the Greater Manchester waste PFI project.

The anaerobic digestion plant produces biogas that in turn is used to generate renewable energy in a combined heat and power module.

The MBT process has two stages. The first stage involves mechanical sorting of the waste. Waste is delivered to a loading bay.

The waste is first fed into a shredder, and is then mechanically separated by size via a trommel screen and by weight via the “windsifter”.

The waste is then sorted into a number of fractions via a series of conveyors:

  • (ferrous and non-ferrous) are recycled;
  • heavy fraction (which tends be glass, stone and large objects that don't get crushed up - an example I saw was a shoe!) goes to landfill;
  • large, light fraction (generally paper, card and plastic) is used as refuse derived fuel (RDF);
  • small fraction (mostly organic material, less than 40mm in size) goes for anaerobic digestion.

The RDF is stored in containers and transported to a power plant in neighbouring Neumόnster to generate electricity and district heat for households and industry.

The small fraction gets mixed with water to form a slurry, which also helps separate out any inorganic fragments (e.g. stone and glass), and is then piped into the anaerobic digestion tanks.

The anaerobic digestion (AD) process takes about 20 days, and produces methane and a liquid digestate.

The methane is used in a combined heat and power (CHP) plant to produce the 1 MW of electricity needed to run the plant, and heat to dry the digestate at the end of the AD process. It is also used in the regenerative thermal oxidiser (RTO) that is used to scrub any waste gases that are emitted from the plant.

The liquid digestate is dried in a series of rotating centrifuges and drums to produce an inert soil-like material (contaminated with bits of plastic) that can be used on brownfield sites or as landfill cover.

Overall, the plant currently processes about 100,000 tons of waste a year, comprising roughly 3% metals, 3% heavy non-recyclable material, 50% RDF material (paper, card, plastic) and 44% organic waste. The outputs are 2.5% metals for recycling, 6% non recyclable material, 48% RDF, 28% to landfill, 17% evaporated water and 500 cubic metres per hour of methane.

 

Key Facts

Treatment Capacity: 100,000 tpa (Current data)
Input Material: Mixed waste 100,000 tpa
Output Products: Recycable Metals 2,500 tpa
No-recyclable metals 6,000 tpa
RDF 48,000 tpa
Residuals to landfill 28,000 tpa
Methane 500 m3 phr

 

Extra Information

Technical Characteristics
AD
  • Approx. 55,000 t/a of the 40-mm-fraction from mechanical pretreatment and approx. 25,000 t/a of sewage sludge
  • 2-stage wet AD, digestors 2 x 5,000 m³ , hydrolysis 1 x 4,500 m³
  • Wet aerobisation of the digestate, subsequent separation of solid/wet matter and thermal drying
  • The dried solid matter ist suitable for landfilling according to the German law (AbfAblV)
Gas Engineering
  • Gas storage tank 800 m³
  • Booster station for 1,200 m³/h of biogas
  • Biogas flare HT type, 7.5 MW
  • Containerised biogas CHP (2 units), 1.9 MWel. / 2.3 kWtherm.
  • VocsiBox® for the treatment of max. 2 x 28,500 m³/h of process air
Water Treatment
  • Containerised membrane plant with ultrafiltration and 2-stage reverse osmosis for the treatment of 2 x 37.5 m³/d of excess water from digestion