Billund BioRefinery (BBR) is an exciting demonstration plant, creating a showroom for some of the best and most innovative Danish environmental technologies treating biowaste and wastewater. It is a Danish lighthouse project where communication of the development processes, results and perspectives is a highly prioritized objective.
The solution is focusing on getting more out of less in terms of energy and resources from wastewater and biomass. The plant consists of two treatment lines complementing each other: A wastewater treatment line and a biomass treatment line. These two treatment lines work in synergy: The wastewater treatment line is producing biomass as a result of the treatment process which is delivered as a co-substrate to the biomass treatment that is producing biogas for energy production in form of electricity and heat that is being sold on the public grid.
The solution is aiming at closing a local resource circle and the plant is furthermore receiving organic household waste from the local municipality and organic byproducts from the local industry. The biogas production is a way of reusing the energy resource from the biomass. The end product from the plant is a completely sanitized organic fertilizer containing the nutrients from the biowaste and wastewater ready to be used for new production in the agriculture.
At the BBR it is possible to see completely new as well as known technologies in a fully integrated solution.
One of the innovations of the project is the demonstration of the Exelys solution. Exelys is a continuously thermal hydrolysis process that is used as an extensive pretreatment of the complex biomass enhancing the biogas production from these substrates to the maximum. The solution is focusing on using less energy to gain more. Therefore the Exelys process is used in a “DLD” configuration; short for “Digestion – Lysis – Digestion”. In this way, the complex substrates; as sewage sludge and household waste, is pre-digested and dewatered before treated with the Exelys process. This reduces the energy input significantly and maximizes the energy production thereby making it possible to produce CO2 neutral electricity from the entire biogas production.
One of the by-products from the biogas process is a production of reject water which is returned to the wastewater treatment line for cleaning with the anammox process. The two treatment lines are linked together by advanced online control strategies assuring; Always optimized biological and chemical processes with respect to the outlet demands of the solution; reduced energy consumption for the processes needing energy supply; the highest energy production from the biomass treatment line and a reliable and stable operation.