Wastewater

Wastewater varies from place to place, which is why we provide flexible products that offer you plenty of versatility in all areas of a waste water treatment plant. They are also efficient enough to cope with the challenges of the future as the global population grows, space becomes increasingly scarce and ever-stricter requirements are placed on us to ensure that we can maintain and improve the quality of the world’s lakes, seas and rivers.

Sjölunda wastewater treatment plant north of Malmö is one of the largest of its kind in Sweden. Some 300,000 people are connected to the plant, which deals with wastewater equivalent to seven full bath tubs every second (approx. 1,350 L/s). At the beginning of April we launched a total solution at the plant for mechanical treatment of a varying flow to guarantee optimum quality and performance.

To tackle mechanical treatment of a varying flow without compromising on quality, in addition to the screenings management equipment at Sjölunda we have also supplied channel gates for guiding and regulating the water flow through the plant. This guarantees optimum performance whether the incoming flow is 400 or 10,000 L/s.

The first screening stage is RSM screens, which have an efficiency rate of >80% and doesn’t require any flush water. The RSM screens have distributor funnels which automatically guide the screenings material to one of the XC320 conveyors. The screenings material is then washed and pressed using six SWP-40 wash presses, with accompanying counter pressure screw, CPS-40. The dry remaining screenings are then led on to the XC500 distributor conveyors, to four containers. For arriving tanker trucks, we have a stone screen that separates large stones and other heavy objects to safeguard equipment further along in the process. All other screenings are pumped into the works and onward into the process.

Martin Hedin, Product Manager at Nordic Water, says the installation uses about 80% less energy than alternative techniques. The treated screenings material ends up with a dry solids content of up to 60%, which means it weights approximately half compared to conventional techniques. The result is a high energy saving and far lower environmental impact for transporting the screenings material.

We have also calculated that the installation, which uses a minimum of energy, should save Sjölunda wastewater treatment plant around 500 kWh per year per screen in normal use. Moreover, the installation requires a minimum of maintenance, partly because it needs no flush water and also runs for as short a time as possible.

“It has been an incredible journey to work on this collaborative project from the start, from problem-solving and project planning, and now final inspection of an ultra-modern treatment works,” says Peter Hjärtstam, Project Manager at Nordic Water.

Sjölunda wastewater treatment plant has also recently signed a three-year maintenance agreement with Nordic Water.

Want to know more about Nordic Water’s solutions for water and wastewater treatment? Visit the product pages or contact us.