Containerised RO Water Treatment Plant for Island Community
Couran Point is a residential community located on South Stradbroke Island, off the coast of the northern Gold Coast. Couran Point Services are responsible for providing water, electricity and other utility services to the community. Bore water is the water source on site and the initial water analysis report showed that the water was high in Conductivity, Total Dissolved Solids (TDS), Hardness, Iron, Turbidity and True Colour.
The existing water treatment plant on site was a simple clarifier that had to be operated manually and did not remove the high TDS and Hardness from the water supply. There was no remote monitoring on plant condition or data logging.
Couran Point Services needed a cost-effective solution to provide the community with safe drinking water. A new water treatment plant that could be shipped across sea to the island and future-proofed for continued growth of the area. Therefore, a containerised water treatment plant with a robust and flexible RO water treatment (reverse osmosis) system was proposed as the recommended solution by FILTEC.
What We Did
FILTEC developed a containerised water treatment plant built within a 20-foot sea shipping container. The container housed media filters (Turbidex and Calcite), a reverse osmosis system, UV disinfection system and hypochlorite dosing units. This containerised solution significantly reduced site and installation labour costs, having the majority of the equipment installed and tested before site commissioning.
The chosen RO water treatment system was a Suez ProFlex LT8-6 RO system. This reverse osmosis system is reliable with flexible configurations to adjust to current water supply demands. The system has the capability to meet compliance needs for industrial, beverage, and municipal applications. Turbidex was used for solid removal as a pre-treatment in the process to avoid raw water entering the reverse osmosis membrane directly in a short period of time. Calcite was used to adjust the pH level post reverse osmosis treatment.
The next stage of this water treatment plant was an Ultraviolet (UV) disinfection system, the Pro50 by Viqua was chosen. This system transfers electromagnetic energy from a mercury arc lamp to a bacterial organism’s genetic material. When UV radiation penetrates the cell wall of an organism, it destroys the cell’s ability to reproduce.
Hypochlorite dosing is applied to the treated water as it is produced, and also to the storage tanks via a recirculation line where a residual is maintained. Grundfos DDA7.5 smart dosing pumps are used, with a Krypton Multi free chlorine and pH analyser by Kuntze to control the dosing rate of the pump. Both pumps and instrument were easy to setup during commissioning and very reliable since the first day of operation.
The entire containerised water treatment plant is controlled by a Master Control Panel with HMI screen. It can be accessed remotely which enables both the client and FILTEC personnel to view the system at any time. FILTEC personnel are able to check alarm history and assist with on-site operation if required.
The main obstacle of the project was to fit and install all the equipment within a 20ft shipping container as well as connecting complex pipe route within a small space inside the container. FILTEC was able to size and fit the equipment accurately through 3D drawings developed in AutoCAD. This allowed a precise 3D overview to be presented to the mechanical installer, reducing time during construction.
The containerised RO water treatment plant successfully treats and produces 6 KL/hour of water to the standards in the Australian Drinking Water Guidelines (ADWG) for the Island community. FILTEC were able to install and build most the required equipment for the plant off-site, saving on project time and cost. The system has been designed to operate automatically and continuously while minimising the total plant footprint. This gives the client flexibility to handle and manage other activities on site. The client was pleased with the treated water quality produced from the plant and the ease of use of the remote monitoring post plant commissioning.
The water quality is significantly improved from the previous system. There are no more issues with scales and residues in residences, and the chlorine residual is more easily maintained throughout the reticulation network to ensure safety to consumers.