The assignment includes the project development and the basic and detailed engineering of the whole project. The separately collected organic household waste from the city of Luxembourg and the surrounding municipalities together with leftovers from supermarkets and kitchen waste are turned into green energy in the biogas plant.

These approximately 30.000 tons/year organic waste streams (annual treatment capacity of the plant) are mixed up with more or less 20.000 tons/year of different agricultural biomass.

The pre-treatment technology of the organic waste consists in a hydro-mechanical system which allows to get out all non-organic components before the anaerobic process.

To avoid any sanitary risks the pre-treated waste is pumped into the hygienisation tanks to be treated for 1 hour at 70°C. After this, the pre-treated waste is pumped into the reactors and mixed up with the agricultural biomass. The anaerobic digestion is done in several digesters and post-digesters.

This final output is partly post-treated thanks to a mechanical separator where two material flows are produced (liquid and solid). Part of the liquid output of the separator is needed as process water for the hydromechanical pre-treatment. The rest of the liquid output is stored and is used as a liquid organic fertilizer on farm land. The solid part out of the mechanical post-treatment is also used as a solid organic fertilizer on the farmland. The biogas which is produced is shortly pre-stored in 3 double membrane gas storage tanks. Before the biogas upgrading the sulfure and the water condensate are taken out. The biogas upgrading is done thanks to a water scrubber where the CO2 is washed out, so to reach natural gas quality. The biomethane is injected to the natural gas grid (± 99% CH4).


Basic information Name of the legal entity: L.E.E. SÀRL
Country: Luxembourg
Project value (EUR): 13.000.000,-
Client: BaKoNa s.à r.l.
Origin of fundings: private
Dates (start-end): 2004 - 2012
Input biogas plant
and combustion
Agricultural biomass: 20.000 tons/year (energy crops, liquid manure, solid manure)
Organic waste 30.000 tons/year (household waste, leftovers from supermarkets, kitchen waste, agro-industrial waste, …)
Technical Data

biogas plant

Technology employed: Biogas (anaerobic digestion and combustion)
Hydro-mechanical organic waste treatment: 2 x 12 m³ (hydropulper)
Grit removal with hydro cyclone: 2 x 10 m³
Sanitary treatment: 3 x 10 m³ (hygenisation at 70°C for 1 hour)
Total reactor volume: 9.600 m³
Water scrubber for biogas upgrading: 300 m³/h bio methane
Biogas burner for process heat: 400 kWtherm (alternative CHP)
Others: Air treatment by biofilter
Energy production
Biogas: 6.200.000 m³/year
Heat demand for the process (biogas burner): 1.000.000 m3/year (biogas need)
Anaerobic process: 1.200.000 kWhtherm/year
Hygenisation: 4.000.000 kWhtherm/year
Biogas processing: 2.600.000 Nm3/year (Bio methane - natural gas quality)
Services provided

Project Planning:

Feasibility study
Mass and energy balance
Authorisation procedures
Call of tender
Engineering design: Basic engineering
Detailed engineering
Financial engineering
Project implementation: Supervision of construction
Start-up of the process planning
Process optimisation