PROJECT: Water Treatment Works (WTW) – Raithby
The existing Water Treatment Works (WTW) at Raithby had reached the end of its life and required a major refurbishment, including a new 15Ml/d iron and manganese removal system complete with disinfection and supply pumps for the production of potable water.
Key features of the new works included:
- Rapid gravity filters to be installed outside at high level to remove the need for an underground pump station.
- Structured wall HDPE contact tanks to reduce capital costs and embodied carbon.
- Standard products to maximise off-site build.
- A modular approach to design to aid fabrication and construction by repetitive processes and techniques.
The key processes underpinning the project were:
- The selected treatment process for the scheme was a conventional iron and manganese removal plant consisting of aeration, oxidation, filtration and disinfection with a high lift pumping station.
- All major items of plant were assessed to determine the use of alternative materials and potential carbon savings.
- A carbon tracker was used through the process to identify where savings were achieved for each major element of plant.
- 17.8M long, Form 4 / Form 2 (Hybrid), Bottom Entry, Front & Rear Access Motor Control Centre.
- Custom Built Galvanised Frame to support both the panel and the suspended floor panels.
- Full Intelligent Control MCC
- 1250A 4-Pole A.C.B. Incomer – Fault Rating 50kA for 1sec.
- Master / Slave Active Harmonic Filtering
- Starter Sections comprising of 6-Pulse ABB Variable Speed Drives, Rockwell Soft-Starts.
- ABB Variable Speed Drives all using ‘Safe Torque Off’ function for Emergency Stop.
- Ethernet Communication to PLC from all Starter Sections for Intelligent Control.
- Stream ‘A & B’ (Form 2) Motive Water Pumps (x2) & Sample Pumps (x3) Drives – (ABB – ACS355). Ethernet communication to PLC. Safe Torque Off Emergency Stop Functionality.
- ICA Section: PLC – Rockwell Control Logix Processor, Ethernet Network for Communication to all Starters, Profibus Communication to external Filter Equipment and Analysers, 3 x 10 Way Ethernet Managed Switches, 32 Way 24Vdc Digital Input/Output Cards, 16/8 Way Analogue Input/Output Cards, 24-Way ABB SMC3000 Chart Recorder.
- HMI – Rockwell 15” Panelview Plus Colour Key/Touch