Wastewater - Turning Problem to Solution

CASE STUDY 1

EXTENDED VERSION

An innovative circular wastewater treatment plant conversion – Billund Biorefinery, Billund, Denmark

Daniel Ddiba

Billund, Denmark, is the home of the LEGO toy company. It is also home to an innovative circular economy wastewater treatment plant. A conventional wastewater treatment plant had been operational since 1996, but because of pressures to reduce costs, increase energy production and generate cleaner water, in 2017, a US$ 12 million public-private initiative converted the facility into the Billund Biorefinery. The facility receives wastewater and solid waste from domestic and industrial sources, treating wastewater for a population of 70 000, as well as 70 000 tonnes per year of sewage sludge and organic waste. Compared with the previous configuration of

the plant, the biorefinery has significantly improved the recirculation of nutrients and energy in the town. Up to 98 per cent of all household wastewater and organic solid waste is now recycled, and the plant has doubled its intake capacity for household and industrial organic waste. Energy production has increased by over 60 per cent, and the plant is a net energy exporter with US$ 1.8 million of revenue from annual energy sales – enough for the annual consumption of 1 600 households. Recovery of nitrogen and phosphorus for the organic fertilizer produced at the facility has increased by about 18 per cent, generating US$ 200 000 in revenue per year.

Schematic of the Billund Biore nery

MANURE AND ORGANIC WASTE FROM AGRICULTURE

ORGANIC FERTILIZER

PHOSPHORUS FERTILIZER

Source: www.billundbiore nery.com

Figure 2.4: Schematic of the Billund Biorefinery. Source: (Billund BioRefinery n.d.).

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