Fluoride

Dioxide Pacific have many years experience in the design, manufacture, installation and commissioning of fluoride dosing systems for potable water. Fluoridation is typically accomplished with safe and accurate dosing of fluorosilicic acid, sodium fluoride or sodium silicofluoride. Fluorosilicic acid is a liquid and both sodium fluoride and sodium silicofluoride are powders.

Dioxide Pacific fluoride saturators are a down-flow design saturation tank suitable for 5kg jars of granular sodium fluoride, with tamper-proof seal and screw lid. Chemical reaches saturation concentration of 4% w/w inside the tank. It is then dosed into the water supply using metering pumps. Please download the SF brochure to view the options available with this system. Once you have selected your preferred configuration via the ident code, you can email it to us and we will provide a quotation.
Dioxide Pacific was engaged to construct a fluorosilicic acid dosing system for a water authority in the south of Victoria with water flow of 20ML/day. The system includes a 15kL bulk storage tank with tanker filling facilities, magnetic level indicator; day tank 250L with weigh cells and transfer pumps; duty and standby dosing pumps on an HDPE backboard; pre-CWS and post-CWS fluoride analysers and central PLC and HMI operated control system. Dioxide Pacific supplied, installed and commissioned the plant. View a 3D presentation of the plant.

Dioxide Pacific was engaged by a Water Authority in Victoria to design, supply and install a fluorosilicic acid storage and dosing facility. This facility is designed to dose 0.8 – 1.0 ppm into a maximum flow of 110 ML/day. The plant installation is an upgrade of an old sodium silicofluoride dosing system which was past its useful life. It was determined that storage and handling of fluorosilicic acid represented a lower OH&S risk than sodium silicofluoride.

The existing sodium silicofluoride plant was installed in two dedicated plant rooms. The first room was for bulk storage of the powder and transfer via conveyor to the dosing room. The dosing room contained a screw feeder, hopper and solution tank where sodium silicofluoride is mixed with dilution water and transported to the dosing point. The powder plant was removed and the bulk storage room converted by installing a concrete storage bund in the floor of the room to house a bulk storage tank for fluorosilicic acid. The dosing room was gutted and upgraded for installation of the chemical dosing equipment for fluorosilicic acid (FSA).

Fluorosilicic acid storage consists of a 10,000L HDPE bulk storage tank with ultrasonic level sensor, point level sensors, 250L day tank with ultrasonic level sensor, point level sensors, weigh platform with load cells and transfer pump. The concrete bund area contains both the bulk and day tanks.

Chemical is supplied by bulk tanker. The tanker is parked in a purpose built concrete tanker unloading driveway. This driveway is designed to comply with EPA Vic Bunding Guidelines and to house a significant spill of chemical should this occur during transfer.

Chemical is transferred from the bulk storage tank to the day tank using a mag drive pump. Chemical dosing is with duty and standby ProMinent Delta dosing pumps. Dosing pumps, dosing pipework and valves are installed in an HDPE dosing cabinet in the dosing room. Concrete surfaces in the bund and unloading area are coated with a chemical resistant paint.

The fluorosilicic acid dosing system is operated from a central control panel which includes an Allen Bradley Control Logix PLC and PanelView Plus touchscreen. Modifications to the site Citect SCADA were made to include the fluoride FSA dosing plant. There are many safety features built into this plant to prevent under and overdosing of FSA including the monitoring of flow from the dosing pumps using a mag flow meter and comparison of actual flow with calculated flow. The system has been built virtually metal free. All fixings, pipe clamps and strut are Fiberstrut vinylester which are fully chemical resistant.

Fluoridated water entering and leaving the clearwater storage is monitored continuously with on-line fluoride analyzers. These fluoride analyzers are used for alarm purposes to shut down fluoride dosing if overdosing occurs. Fluoride residual is controlled through flow pacing within tight concentration limits specified by DHS.

Dioxide Pacific was engaged by a Water Authority in Victoria to design, supply and install a fluorosilicic acid storage and dosing facility. This facility is designed to dose 0.8 – 1.0 ppm into a maximum flow of 509.2 L/s. This is a new installation and included construction of a colourbond plant room shed.

The new fluoride dosing plant room contains separate concrete bund areas for the 10,000L bulk storage tank and 250L day tank. Fluorosilicic acid storage consists of a 10,000L HDPE bulk storage tank with ultrasonic level sensor, point level sensor, 250L day tank with ultrasonic level sensor, point level sensors, weigh platform with load cells and transfer pump.

Bulk tanker deliveries are arranged to transport chemical to regional sites in Victoria. When the tanker arrives on site, it reverses into a purpose built concrete tanker unloading driveway which is below ground level at the lowest point. This driveway is designed to comply with EPA Vic Bunding Guidelines and to house a significant spill of chemical should this occur during transfer.

Chemical is transferred from the bulk storage tank to the day tank via a mag drive pump. Chemical dosing is with duty and standby ProMinent Delta dosing pumps. Dosing pumps, dosing pipework and valves are installed in an HDPE dosing cabinet mounted on the plant room wall and draining into the day tank bund. Concrete surfaces in the bund and unloading driveway are coated with a chemical resistant epoxy paint.

The fluorosilicic acid dosing system is operated from a central control panel which includes an Allen Bradley SLC 5/05 PLC. The fluoride dosing system includes many safety features and interlocks to prevent under and overdosing of FSA including the monitoring of flow from the dosing pumps using a mag flow meter and comparison of actual flow with calculated flow. As always, this system has been built virtually metal free. All fixings, pipe clamps and strut are Fiberstrut vinylester which are fully chemical resistant.

Fluoridated water entering and leaving the clearwater storage is monitored continuously with on-line ProMinent Dulcometer fluoride analyzers. These fluoride analysers are ion selective electrodes with high accuracy and reliability and do not require buffering with TISAB. The fluoride analyzers are used for alarm purposes to shut down fluoride dosing if overdosing occurs. Fluoride residual is controlled through flow pacing within tight concentration limits specified by DHS.

For more information on fluoride dosing systems or to obtain a quotation, please complete the feedback form on our Contact page.