[ Water & Wastewater ]
[ Water & Wastewater ]
The wastewater treatment plant has an average inflow of 4 ’ 000 liters per second
Driving sustainable solutions to wastewater treatment
The Gryaab wastewater treatment plant handles all the effluent from the greater Gothenburg area , the second largest city in Sweden . Its state-of-the-art design minimizes energy consumption , with advanced treatment processes removing waste and converting it to organic soil enhancer or using it to contribute to the local district heating system . three , reducing the capital expenditure ( CAPEX ) as well as the operational energy requirement . All the debris collected by the screens is transferred by four MevaSpiral XC360 conveyors to the two MevaPress SWP40 wash presses , which are installed with MevaPress CPS-X50 counter pressure screws .
Text & images by Sulzer
At the heart of the water cycle is the wastewater treatment plant ( WWTP ), which has the unenviable task of removing all the waste products and debris before the water is returned to the local environment . Operators aim to maximize efficiency and reduce operating costs where possible , while still meeting the high water quality standards required by local and national legislation . At a WWTP in Sweden , the municipality had already replaced the existing fine screens and recently also changed the compactor systems , which has delivered considerable savings in terms of energy efficiency and maintenance costs .
Increasing throughput and efficiency However , the old , now replaced fine screens at the inlet to the works had been suffering from considerable issues with reliability , and maintenance costs were rising year on year . A project to replace the screens commenced and Nordic Water won the contract based on the equipment , the design of the new screening system and the projected economic and environmental savings offered over the original arrangement . Based on flow rates averaged over the year for a connected population equivalent of 800 ’ 000 , the screens were calculated to have a water flow capacity of 10 m 3 / s and a screenings throughput of over 16 m 3 / hour . Nordic Water proposed 11 MevaScreens RSM connected to conveyors and compactors to minimize the volume of the waste . To make the project even more costeffective , Nordic Water ’ s plan was to use two compactor lines instead of
Bigger is better The CPS-X50 is the latest range-topping addition to Nordic Water ’ s counter pressure screws . To deliver the required increased capacity over the CPS-X40 , the engineers retained the essential design , which has proven reliable for many years , but up-scaled the shafts and bearings to improve mechanical strength . However , the challenge came in testing the new design . The increased capacity meant that any testing had to be completed on a large treatment works that can supply the high volumes of wastewater required . The site in Sweden proved ideal - the planned upgrade to the inlet screens would fit perfectly with the new counter pressure screws . The 11 new MevaScreen RSM were installed in a staged process that enabled the treatment plant to continue operating as normal throughout the project . The new equipment is some of the most efficient on the market , which
42 Stainless Steel World March 2024 www . stainless-steel-world . net