From Water and Wastewater.com
New Treatment Standards For Effluent Re-Use at Coffs Harbour
By Amiad Filtration Systems
Apr 25, 2005 - 2:45:00 PM
Coffs Harbor, Australia -- Amiad Australia in conjunction with Advanced Pumping & Irrigation of Coffs Harbour, recently commissioned a tertiary filtration & treatment system for the Coffs Harbour City Council (CHCC). The filtration system provides a tertiary treatment of secondary treatment effluent.
Coffs Harbour is a coastal town with a population of 60,000, in Northern New South Wales, Australia. The need for tertiary filtration evolved as a result of the community's interest in better environmental solutions for effluent reuse and reduced discharge via ocean outfall.
Due to the diverse range of users within the re-use water reticulation system, flow demands upon the system vary widely (18 - 318 m3/hr). The system has to provide a water quality that conforms with the current Environmental Protection Authority guidelines for effluent re-use which are thought to be the toughest in the world.
System Overview
The process begins with pre-filtration of the secondary effluent with an Amiad EBS filter, Adjacent to this pre-filter secondary chlorine injection is undertaken in order to oxidize organic & bacterial content.
Further downstream alum is injected and subsequently mixed. The physical separation of this process from the media filtration site provides necessary contact time for both the chlorine & alum.
The heart of the process is the filter site which comprises 18 of the Model 97 filter vessels. The Amiad design provides a modular system of 18 deep-bed media filters. Each vessel is equipped with a valving control assembly that ensures a balanced flow throughout the system. The hydraulic balance in each vessel guarantees the designed filtration speed to be maintained without human intervention (the filtration speed is a critical part of the process in achieving the required NTU levels).
The filtration process has been enhanced by using three different media types within each vessel. The media performance is aided by an air scour prior to back washing. Clean filtered water is used for the back-wash process, which is then returned to the humus tanks for further recycling via the secondary process.
The final step in the process, prior to delivery to the council's end users, is the tertiary chlorination of the filtered effluent. The dosing system for all chemicals is flow based, allowing the accurate input of chemicals across the flow range of 18 - 318 m3/hr. To ensure health & safety to its clients, the council has specified a faecal coliforms level less than 10/100 ml, regardless of flow. Amiad's system is currently achieving a better quality than this.
A custom built switchboard and control system has been installed to operate and monitor every aspect of the system's performance. It has full remote reporting capability and the program can be accessed via modem, providing 24 hour support if required. The re-use of water is employed in a full range of activities: watering sports fields, golf courses, parks and gardens, as well as in roadmaking.
Amiad is proud to be associated with new environmental standards for effluent filtration, and for being involved with projects that have significant tangible benefits for both the community and the environment.
For more information contact:
Amiad Filtration Systems
D.N. Galil Elyon 1
12335, ISRAEL
Telephone: +972-4-6909500
Fax: +972-4-6909391
Email: info@amiad.com
Website: http://www.amiadusa.com/
© Copyright 1998 - 2008
Water and Wastewater.com