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.

dws-nijhuis-wibo-one-step-nieuwenhuijzen-350pxImproved 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.

Four processes
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.

This news items was originally published on the website of Nijhuis Industries and Witteveen+Bos.

 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

More information
Nijhuis Industries
Doetinchem, the Netherlands
+31 314 749 000

Deventer, the Netherlands
+31 570 69 79 11

The principle of the 1-Step filter is explained in this video.