11 feb 2020

Nereda® technology is renowned as being a far more environmentally friendly solution of treating wastewater than traditional methods, which use many chemicals. Nereda also uses much less energy making it more effective to operate and further reducing its environmental impact. In addition to these advantages, one of the most significant factors in the Nereda system’s benefits is its comparatively small physical footprint. A typical Nereda treatment installation needs up to 75% less space than the build area of a traditional plant.

One single reactor

This significant reduction in space required is down to the fact that with Nereda the nutrient removal process takes place in just one single reactor. Additional tanks, including primary and secondary clarifiers, selector basins, anoxic, anaerobic and aerobic compartments are often not necessary. Also, the biomass operates at a higher concentration, so the single tank has a greatly increased treatment capacity.

Faster purification process

The award-winning Utrecht Nereda wastewater treatment plant was built alongside an obsolete treatment works, which had been constructed in 1959. The new plant removes twice as much nitrogen and phosphate from the water but is much smaller. The original plant had 14 sedimentation tanks in use, which have been replaced by just six Nereda tanks. The purification process of the new plant is much faster too, so as well as being considerably smaller, it is 30% more energy efficient compared to the original plant.

Garmerwolde WWTP in the Netherlands serves 350,000 people. The existing plant, with a two-stage activated sludge system needed an upgrade to increase its efficiency and output. Two Nereda tanks were built to treat around 40% of the sewage coming to Garmerwolde and operate in parallel with the existing works. These two tanks take up less than a quarter of the space occupied by the existing plant. Coincidentally, Nereda exceeded expectations at Garmerwolde and now treats 50% more wastewater than originally planned – 60% of the plant’s total output.

Short on space, big on efficiency

The advantages of a Nereda plant being so much smaller than a conventional one are clear. Wherever land is in short supply, such as in an urban area or where Nereda is being retrofitted into an existing plant with very little space available, the smaller footprint is ideal.

Another European plant that needed an upgrade was Ringsend in Ireland. With Ringsend being an inner suburb of Dublin, only two kilometres from the city centre, there was only a small space available on an undeveloped plot on the existing site to build an extension. This facility requires massive capacity, with 40% of all Irish wastewater being treated there. The upgrade was essential to address the overloading of the facility and to enable the plant to meet necessary treatment levels.

First for the Philippines

The first Nereda plant to be constructed in the Philippines is currently under construction at UP Arboretum, UP Diliman Campus in Quezon City. Space is at a premium here as well, so the footprint needs to be as compact as possible, without compromising on performance. Once complete, the new treatment works will treat 5,000m3 per day, taking up significantly less space than traditional treatment options.