Posted on 9 March 2018
Two Dutch firms, Nijhuis Industries and Witteveen+Bos signed a memorandum of understanding on the worldwide roll out of the 1-Step filter technology for the additional treatment of effluent from waste water treatment plants.
The 1-Step filter is an effective modular and compact fixed bed activated carbon filter, operated at a relatively high rate downward flow.
The MoU was signed by CEO Karin Sluis of Witteveen+Bos and CEO Menno Holterman of Nijhuis Industries, on 5 March.
Improved wwtp effluent quality
The 1-step filter is a cost-effective solution to improve the effluent quality of municipal sewage treatment plants. As an additional treatment the filter removes total suspended solids, nitrogen, phosphorus, organic micro-pollutants and medical residues, all at the same time.
Since 2013 onwards, the Amsterdam water utility Waternet operates the first ever 1-Step filter at their wwtp Horstermeer with a capacity of 165,000 population equivalent (on top photo).
Wwtp Horstermeer is equipped with a full scale 1,550 m3/h 1-Step filter which was installed to meet the stringent total nitrogen (5 mg/l) and total phosphorus (0.3 mg/l) limits, imposed by the EU Water Framework Directive, whilst also future-proof wwtp Horstermeerand enabling it to achieve possible future discharge limits for organic micro pollutants.
The 1-step filter combines four treatment processes into one single treatment unit. In addition to the removal of suspended solids by filtration, nitrogen is simultaneously removed via biological denitrification (using a selective carbon source), chemical phosphate and heavy metals are removed by coagulation and flocculation (with a low dose of metal salt), and, if required, organic micro pollutants can be removed by adsorption onto the activated carbon.
Read also on this website
● Nijhuis Industries joins effluent polishing research project on O3GAC-technology, 28 March 2017
● World's first 1-Step filter officially commissioned for effluent treatment at wwtp Horstermeer, the Netherlands, 28 November 2013
● Expertise: Water technology
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The principle of the 1-Step filter is explained in this video.