Fluoride is very common element, found in earth’s crust. It exists in the form of fluoride in a number of minerals like fluorspar, cryolite and fluorapatite.

Fluoride enters in the aquatic system in the dissolved form through industrial discharge form through aluminium industries, phosphite industries, coal plants etc.

Higher concentration in drinking water can affect the health adversely. The World Health Organization (WHO) guideline for fluoride is 1.5 mg/liter in drinking water. As per IS 10500 standard the desirable limit for fluoride is 1 ppm and permissible limit is 1.5 ppm in drinking water.

Health Hazard
Above 2 mg/l – Gives chalky white appearance to permanent teeth
Above 4 mg/l – Causes dense and brittle bone condition, known as Osteoporosis and Skeletal Fluorosis.

SHIVAM provides a wide range of following processes to filtration of fluoride from water:-

FROM ACTIVATED ALLUMINA:

A new activation technique using alumina was developed for the removal of fluoride from water.
shivam provides 2 stage processes for filtration and fluoride removal. In the first stage,water passes through a coarse filter pad (washable) to remove suspended particles. The filtered water is then passed through an Activated alumina media capable of removing fluoride from   water. The fluoride is adsorbed on the surface of media. The media has high surface area with larger pore size, and provides better diffusion. The fluoride free water is then passed through  second stage of filtration with filter dome, which not only retain the media in place but also provide polishing filtration.
The media can be regenerated on exhaustion, several times. 

Features:

• The unit  is of domestic candle filter design
• Vessel material is of Stainless Steel or plastic
• Selection of media (capacity, life, regenerable & non-toxic)
• Provide means of filtering water
• The unit is capable of handling fluoride up to 10 ppm and consistently give outlet water with < 1.5 (or 1 ppm) fluoride)

 FROM RESINS :

The process segregates the removal of fluoride and fluorosilicate ions, from the totality of ions in the waste water stream, thus improving treatment efficiency and reducing costs. Ion-exchange chromatography is used to remove the fluoride and fluorosilicate ions by passing the wastewater stream through one or more columns that contain a charged resin which selectively binds cations/anions in the stream. The fluoride ions are washed from the column and then collected for removal or use in other processes.

SHIVAM Fluoride Removal plant based on Resin technology unit consists of an FRP vessel with Ion Exchange resin which can be connected directly to the hand pump through a flexible pipe. Treated water will be collected in a storage tank into which sodium hypochlorite will be added by gravity for disinfection of water.

Features:

• The unit is steardy and easy to handle.
• Can be operated by an unskilled person.
• Do not require electricity.
• Long life.
• Low operating cost of treated water.
• Can be used in remote areas.  

FROM ELECTRO CO-AGULATION:

A process to remove free and/or complex fluoride and cyanide species from wastewater that comprises the steps of removing fluoride species from the wastewater; and passing the wastewater through an electrocoagulation reaction chamber to remove cyanide species.

Electrochemically generated aluminum can remove most contaminants present in water and wastewater by precipitation and adsorption. Through the process of electrolysis, coagulating agents such as metal hydroxides are produced. The aluminum species act as a coagulant by combining with the pollutants to form large size flocs and then can be removed by settling and flotation (electrocoagulation/flotation process).

FROM RO:

The best way to remove fluoride from drinking water is reverse osmosis. Any good  reverse osmosis unit removes about 95% of fluoride by its nature. No special filters or setup is needed. Reverse Osmosis (RO) systems are not only very efficient at removing a wide range of chemicals, heavy metals, and bad taste / odour, but they will also remove fluoride, and all other dissolved solids from the water which normal Water Purifiers will not remove.  Dissolved solids are minerals and salts which are dissolved into the water. RO system is useful to remove fluoride as conc. is as high as above 4-5ppm.