Water and Effluent Treatment Magazine
Issue link: https://fhpublishing.uberflip.com/i/632952
The concepT • The RakeMax Multi-Raked Coarse Screens handle 2,200l/s per screen working in a duty/ assist/ assist/ standby mode with control panels for each unit. • There are WAP-L Washpress units for coarse screenings handling, with each unit handling 9.18m3/ hr per unit working on a duty and standby basis with the facility of working on a duty and assist basis if required with control panels for each unit. • WAP-L Washpress units for the fine screens with each unit handling 12m3/hr working on a duty and standby basis. Existing launders with some minor modifications could be used The screens were reassembled on site The end result proved 'very rewarding' FEBRUARY 2016 WeT neWS 13 to ensure that its Scottish installation teams had the required drawings, parts and detailed information to reassemble the units onsite, work which would normally be undertaken in its workshop. Further consideration was required regarding the phases and order in which the machines would be installed. Huber worked closely with Scottish Water to formulate a plan that met its requirement of keeping the plant operational whilst Huber's new equipment was installed mechanically, electrically and commissioned. Whilst the installation of the coarse screens was being completed, Huber also replaced the fine screens' screenings handling units with large variable speed Huber WAP-L screenings handling units. Each WAP-L was rated at 12m3/hr at standard speed with the possibility of increasing the speed of the motors up by the use of VSDs (variable speed drives) to give an output in excess of 15m3/hr per unit. This was achieved by the sensing of the screenings level within the unit's inlet hopper and when a set criteria was reached, and only at that time, the VSD would come into play and give the necessary high speed removal capacity. VSDs were also fitted to the coarse screen Washpress units to improve flexibility. Storms The project budget, timescale, and operational requirements were achieved as a result of the good working relationship and close collaboration and communication between all parties. Large storms have already been experienced at this site and from the site operational feedback and response no issues have arisen. Jim Gordon, project manager at Scottish Water, says: "The Meadowhead Inlet Refurbish- ment was a very challenging project on a number levels including a very tight timescale. Key to the success of delivering this on time was an effective and efficient working relationship between Huber, SW Managed Delivery, SW Operations and the main contractor, with all parties meeting their respective project commitments on or ahead of schedule. "Huber as the principal supplier and installer of screens and screening handling kit had a key role to play in meeting the aspiration of the delivery team to better the agreed programme and have all screening equipment installed and operational by Christmas 2014 rather than March 2015." Fred Neumann, Huber area sales manager, comments: "The success of this project was down to all the associated stakeholders being involved early in the project design and execution. Everyone involved, adopted a very professional, flexible approach and 'can do' attitude, which resulted in a very good installation on the ground for all to see. Personally, I would have no problems undertaking future projects with such a hands-on end-user / project manager and contractor involvement." neeD To KnoW 1 Large grab screens had to cope with large variations in flow from catchment pumping stations 2 The RakeMax was split into sections for transportation with re-assembly on site 3 Issues with planned maintenance activities and lifting strategies had to be considered 4 The existing launders with some minor modifications could be used, reducing the overall project costs The VeRDIcT "This was a very challenging project on a number of levels, including a very tight timescale. Key to the project's success was all parties meeting their respective project commitments on or ahead of schedule" Jim Gordon, project manager at Scottish Water