Project Description
Dyserth Sewage Treatment Works (STW) is a medium sized trickling filter works. Under the Water Framework Directive (WFD), the site had to meet a new total phosphorus (TP) consent of 0.5 mg/l, and an Iron consent of 4 mg/l.
To achieve these new consent standards, MMB (Welsh Water’s delivery partner) installed a FilterClear® plant with ferric dosing upstream of primary settlement. Provision was made for a 2nd point ferric dose into a static mixer upstream of the FilterClear® plant, but
this has not been necessary.
The decision was based on a comprehensive whole life cost (WLC) assessment of various tertiary solids removal (TSR) plants.
The FilterClear® skid was assembled and hydraulically tested off-site at Bluewater Bio’s works, before being transported to site for installation on a flat concrete slab.
| Project Name: | Dyserth STW |
| Client: | Welsh Water |
| Capacity: | 29 L/s |
| Main Contractor: | Mott MacDonald Bentley |
| Project Scope: | Design, supply & commission |
Project Highlights
• Off-site manufacture
• Consent of 0.5 mg/l TP and 4 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® 3V1260 plant. Fully automated and instrumented tertiary filtration system for total phosphorus removal.
Project Duration
FilterClear® delivered: Mar 2020
Installation time ~ 2 weeks
Commissioning time ~ 2 weeks
Compliant by: July 2020
Client Contact
Client organisation: Welsh Water
Contact person: Richard Matthews
Dyserth STW Process Parameters
| Average Flow | 1,021 m3/d |
| Maximum Flow | 2,506 m3/d (29 l/s) |
| Design Influent TSS conc. (incl. allowance for chemical dosing) | 28 mg/L (average) 46 mg/L (98%ile) |
| Effluent TP consent | 0.5 mg/L (average) |
| Effluent Fe consent | 4 mg/L (95%ile) |
