DNF (Denitrification Filter) at Blijdorp Zoo in Rotterdam
Challenge and Solution
DNF was designed and tested in collaboration with Blijdorp Zoo, Thalassa, and ATO Energysaving.
Results to date (from September 2024 to October 2025)
- Nitrate reduction efficiency of 80–90% in the effluent
- Reduction of approximately 31 kg of NO₃ per month
- The nitrate concentration in the basin is 85 mg/l
- No increase in nitrite concentration in the basin
- Equivalent to approximately 1,300–1,500 m³ of water saved on water changes during this period
- Reduced NaOH consumption for maintaining alkalinity and pH
Shark Tank
- 3,000 m³ total volume
- Under normal operating conditions, a 70 m³ water change is performed weekly
- Nitrate concentration of 100–110 mg/l
- Nitrite concentration 0.015–0.03 mg/l
- pH 7.85–8.05
- Alkalinity 2.5–3.0 meq/l
- DNF installed in March 2025
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From Idea to Reality
Advice
We'll start with a consulting phase during which we'll work together to explore how processes can be made more efficient and sustainable.
Design
Based on the application, we design customer-specific systems that are efficient, sustainable, and fully customized.
Construction
We build the systems entirely in-house, with a focus on quality, sustainability, and precision.
Installation
Our installation teams install the systems at the desired location, both domestically and abroad.
Maintenance
We provide maintenance and support to ensure that the systems continue to operate reliably, efficiently, and for a long time.
We're happy to help !
Please contact us. We’d be happy to assist you with advice and information about our plastic processing systems.
