Overview

NuReDrain Highlights and Achievements – Update May 2020

Plants need nutrients, such as nitrogen (N) and phosphorus (P), to grow. Therefore, nutrients are used in agriculture. The excess of nutrients end up in the water and deteriorate the water quality. The NUREDRAIN project wants to tackle this problem by testing filter technologies which can trap N and P. 

The Nuredrain project considers 3 N removal technologies: 1/ a MBBR (= moving bed bio reactor); 2/ a ZVI (= zero valent iron) filter and 3/ a mobile constructed wetland. 

Greenhouse effluent has been treated with a DIY MBBR (= do-it-yourself moving bed bio reactor) filter. An average removal efficiency of 85% could be achieved. Also drainage water can be treated with an MBBR. The configuration of the MBBR filter for drainage water depends of the flow and N concentration. Average removal efficiency is about 64%. The ZVI filter has for the first time been tested in the field. N removal was very successful being on average 94%. The mobile constructed wetland has been installed along a ditch. N removal results are expected in the near future.  

The Nuredrain project also considers 4 P removal technologies: 1/ a P filterbox; 2/ a sediment filter combined with a reactive filter3/ an inline drain P filter and 4/ a filter column. 

Drainage water treated with the P filterbox achieves a 80-100% P removal. The associated filter material used is ICS (= iron coated sand). This filter material has also been tested for P removal in greenhouse effluent. ICS showed to be a very good P adsorbent as 99% P could be removed. When a lot of sediments are present in the drainage water, it is recommended to trap the sediments first. A hydroseparator has been trialed for this in Denmark but pump failure caused problems, also on the subsequent reactive filter. Only 22% P removal could be achieved. Also drainage water in Germany can be very rich in amorphous organic matter. This disturbs the adsorption potential of P onto ICS resulting in only 7% of P removal. 

40% of P can be desorbed from saturated filter materialThe resulting P quantity is too low to be economically viable for P recovery. Desorption is nevertheless interesting to recover the filter material as such.  

Techno-economic evaluation of 3 nutrient filter systems revealed that these technologies are more cost effective as compared to current measures. This result will strengthen the discussion with national authorities.  

Handy men and women can try to build themselves a MBBR by following the guidelines in the manual.  

NuReDrain Highlights and Achievements – Update May 2019

NuReDrain Highlights and Achievements – Update November 2018

NuReDrain Highlights and Achievements – Update May 2018

NuReDrain Highlights and Achievements – Update November 2017