Ros Roca envirotec has received a contract of more then 18 Mio. € to supply as general contractor for technology and civil works one of the biggest agricultural biogas plants in Dorsten, Germany. The plant is designed to treat 130,000 tonnes per year of manure and energy crops and will produce approx. 22 million m3 of biogas per year which corresponds to an hourly biogas production of 2.500 m3/h.


As the permission to build the plant was already issued Ros Roca envirotec can start with the construction of the biogas plant immediately. It is a "turnkey" supply including the biogas technology and the biogas upgrading system. It also includes the start-up of the whole plant. First biogas will already be produced in 2011 from the plant.  

The biogas plant is using a completely automatized feeding system mixing fresh substrate with manure and recirculated biomass to assure optimized retention time and highest possible biogas production in 8 digesters with central stirrers. The process design assures highest possible flexibility of substrate feeding into the different digesters and allows to adjust optimized substrate mixtures in the feeding system.   

The process realized from Ros Roca envirotec includes two biogas upgrading units to process the raw biogas. Carbon dioxide is removed very efficient by a pressurized water scrubber technology (Ros Roca technology) and bio methane with a methane concentration of 97 – 99 % is produced. The bio methane is then directly injected into the natural gas grid and consequently highest efficient energy valorisation is guaranteed. The bio methane can be used as green gas directly by the consumer or can be used for combined heat and power production in off-site CHP units which is the most favoured way of bio methane utilization in Germany. The plant also produces high quality fertilizer which is then used directly in agriculture.

The plant will be installed directly in an industrial area and it is equipped with very efficient odour collection and treatment facilities to avoid odour emissions.