Project Description
Harby STW is a small trickling filter works in Nottinghamshire, treating domestic sewage and trade effluent, containing dairy wastewater from a cheese factory.
In AMP6, under the Water Framework Directive (WFD), the site was upgraded to meet more stringent discharge standards, including a new total phosphorus (TP) consent of 0.25 mg/l, and Fe of 2.5 mg/l. To achieve these new consent standards, Nomenca (Severn Trent’s main contractor) installed a chemical dosing facility
and a FilterClear plant. The decision was based on a comprehensive whole life cost (WLC) assessment of various tertiary solids removal (TSR) plants.
The FilterClear skid was fully assembled, tested and commissioned off-site at Bluewater Bio’s works, before being transported to site for installation on a flat concrete slab.
| Project Name: | Harby STW |
| Client: | Severn Trent |
| Capacity: | 36 L/s |
| Main Contractor: | nmcn Plc |
| Project Scope: | Design, supply & commission |
Project Highlights
• Off-site manufacture
• Consent of 0.25 mg/l TP and 2.5 mg/l Fe
• Rapid installation and commissioning
• No separate flocculation tank needed
Scope of Works
Design, procurement, manufacture, installation and commissioning of Bluewater Bio’s proprietary FilterClear 3v2040 plant. Fully automated and instrumented tertiary filtration system for Total Phosphorus removal.
Project Duration
Award to delivery to site ~ 12 weeks
Installation time ~ 4 days
Commissioning time ~ 8 days
Harby STW Process Parameters
| DWF | 1,200 m3/h |
| FFT | 3,076 m3/h (36 l/s) |
| Design Influent TSS conc. (incl. allowance for chemical dosing) | 49 mg/L (average) 111 mg/L (95%ile) |
| Influent TP concentration | 1 mg/L (95%ile) |
| Effluent TP consent | 0.25 mg/L (average) |
| Effluent Fe consent | 2.5 mg/L (95%ile) |
