Arla Foods is at present Europe’s second largest dairy company, cooperative
society owned by approximately 10,600 dairy farmers,
with an annual turnover exceeding 6 billion EUR.
Arla Foods’ highly optimised production facility in Hobro, Denmark,
processes around 140 million litres of liquid milk into fresh milk
and sour products every year.
The Situation
Arla Foods in Hobro has been facing high and increasing discharge
costs for wastewater during recent years as a result of a pollutionbased
cost model implemented by the local municipality.
For some years, Arla Foods had investigated several wastewater
treatment technologies in order to try to reduce their discharge
costs. Because Arla Foods in Hobro is situated in dense urban settings,
and furthermore neighbouring an odour-sensitive camping
site, they were unable to find a technology that could meet their
requirements to cost reductions, space savings and environmental
soundness, until they were presented to the Grundfos BioBooster
PBR technology.
The Grundfos Solution
Grundfos BioBooster performed an analysis of Arla Foods’ current
wastewater situation, and prepared a feasibility study to calculate
investment and expected cost savings, thereby providing the customer
with a good basis for decision.
The outcome was a BioBooster plant which at present consists of 23
Pressurised Biofilm Reactors (PBR). However, capacity expansions to
accommodate future increases in production volume at Arla Foods
are done simply by the addition of further PBRs.
The BioBooster plant is connected in series with the existing ZEDA
flotation unit, which partly removes oils, fats, proteins and other suspended
solids from the wastewater. Also, to keep initial investment
costs at a minimum, both the existing sludge tank and balancing
tank system were reused. The biological sludge is separated from
the wastewater stream on a belt filter and pumped to the existing
sludge tank. The sludge from the flotation unit and the PBRs is subsequently
recycled in a biogas plant for biogas generation.
The BioBooster plant is completely odour-free, as all vents from the
enclosed reactors, including all other vents and open areas where
the wastewater is in contact with the air (primarily the belt filter),
are run through activated carbon filters before discharge to the surrounding
environment. This completely eliminates odour emissions
from the plant.
The plant could easily have been fitted into the basement of Arla
Foods’ production facilities. But because the customer wanted to use
this for other purposes, it was decided to build a new, small 62m2
building to house the compact BioBooster plant. Furthermore, the
BioBooster building is cladded on the exterior to ensure maximum
blend with the existing building architecture on the premises.
A comprehensive service agreement comprising planned maintenance,
repair, remote operation and monitoring of the plant formed
part of the complete turnkey solution from Grundfos. This means
that Arla Foods’ personnel have very little involvement in the daily
running of the BioBooster plant.
The Outcome
After commissioning of the BioBooster plant, Arla Foods is gaining
substantial savings on their discharge costs, as well as better documentation
of what is going down the drain.
Better documentation and increased knowledge about the dairy
production’s impact on BioBooster plant operations have led to an
increased awareness within the dairy. Arla Foods’ personnel are now
more focused on reducing spillages in the production, and so far
milk spillages have been reduced by around 400-1000 litres per day.
Due to the high biogas potential in the sludge, a biogas plant has
agreed to collect the sludge at no cost for the dairy, which has
reduced the operating cost of the plant.
The local municipality was informed about the project at an early
stage and has therefore been very positive towards the new technology.
Thanks to Grundfos’ pilot project, they now consider the
new decentralised wastewater treatment technology a viable
alternative to centralised treatment of large industrial dischargers’
wastewater.
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- Complete turnkey installation
- Compact, easy expandable and odour-free solution
- Cost savings
- Complete service agreement
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| The 23 PBRs are installed in vertical layers to ensure max. compactness and flexibility in case of future expansions. |
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| Remote monitoring of the BioBooster plant at Arla Foods in Hobro. |
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| Flow |
225 m3/day |
| Influent |
2300 mg BOD5/litre and 115 mg N-total/litre |
| Effluent |
400 mg BOD5/litre and 80 mg N-total/litre |
| Total installed capacity |
580 kg COD removed/day |
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“We have examined various new technologies on the
market, aiming to find a solution that could reduce our
wastewater treatment discharge costs, and at the same
time meet our requirements to environmental soundness.
By far, Grundfos BioBooster came out as the most
attractive solution.
This was primarily due to its very compact design.
What’s more, the cooperation with Grundfos Bio-
Booster has been characterised by partnership rather
than a traditional customer-supplier relationship. We
are extremely satisfied with BioBooster’s performance
so far – and the solution is very attractive not only for
Arla Foods in Hobro, but also for several other Arla
production facilities”.
Nils Mogensen, Environmental Coordinator,
Arla Foods, Hobro
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