Due to a combination of sewage load growth and performance of the existing feed sludge pre-thickening systems, the ETP sludge digestion system is approaching the limit of its capacity to maintain its target Solids Retention Time (SRT). For these reasons, an augmentation to digester capacity is required.
The purpose of the project is to increase sludge digestion capacity without building additional digester tanks, by implementing Recuperative Thickening to increase the digester solids concentration from its current value of 2.5%. This will enable the target digester SRT to be maintained as feed sludge flows and loads grow over time.
A new thickening system with supporting infrastructure and ancillary services will be required, as well as other works as needed to ensure that existing sludge pumping, mixing and heating systems continue to operate to the Stage 1 design horizon with no adverse impact to existing performance as the digester solids concentration increases.
The recuperative thickening upgrade is intended to be delivered in two stages, with this project comprising Stage 1. Stage 2 will be the subject of a separate business case and capital project.
Scope of Work
The scope of services for the Project includes the following activities within the defined battery limits:
- Detailed design
- Project management
- Procurement and logistics of equipment, bulk materials and consumables
- Construction equipment transport, cranage and logistics for the project
- Provision of all labour, plant, equipment, supervision and all other items necessary to perform the work as detailed, including
- Civil works (earthworks, inground piping, roadworks)
- Concrete structures (slabs, building foundations)
- Primary and secondary structural steel
- Mechanical and piping installation
- HV electrical installation
- Electrical, Instrumentation and Controls installation
- PLC and SCADA programming and integration
Key Staff Involved