flouride removal ppt by pmd.rafi,mtech (svu)
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- FLOURIDE REMOVAL VIA ELECTROCOAGULATION
- INTRODUCTION Fluorine is one of the elements essential for humans. Fluoride exists in the environment through both natural and anthropogenic sources . However, high concentrations of fluoride have adverse effects for human health and higher animals . Drinking water standards for fluoride according to World Health Organization is 1.5 mg/L as the maximum concentration .
- In parallel with the growing requirement for fluoride control several methods have been developed to treat fluoride from drinking water. Presently chemical precipitation , coagulation, adsorption , membrane technologies and electro coagulation methods are commonly used for the treatment of fluoride from water.
- Anthropogenic sources of fluoride are; aluminium industry, semiconductor industry, steel production, glass processing, phosphate fertilizer production, coal processing plants, oil refineries and other miscellaneous activities . Due to pollution from these industries high concentrations of fluoride given in water sources creates problems for many of the living organisms. Therefore, the need for removal of fluoride from sources of natural water and wastewater is ever increasing.
- Electro coagulation process is one of the electrochemical methods that has been developed for water and wastewater treatment. A variety of pollutants can be treated by the electro coagulation method. In this context, a number of scientific works have demonstrated that fluoride can be effectively removed via electrocoagulation process. Removal of fluoride by electrocoagulation method is realised by using iron and aluminium electrodes. Fluoride removal by electrocoagulation is a relatively new process. The process has been developed within the last decade.
- The removal of fluoride is based on the formation of a co-precipitate with aluminium hydroxide flocs that can also be conceived as an adsorption process.
- Material And Methods Sodium fluoride (NaF) was used in this study for the preparation of synthetic fluoride samples. All the solutions were prepared with double distilled water. Batch type experimental studies have been conducted in order to provide information about fluoride removal. A laboratoryscale, monopolar electrocoagulation reactorwas designed and constructed .
- For the analysis of fluoride two methods are suggested by Standard Methods . Ion Selective Electrode Method and SPANDS Method.
- The main parameters of electrolyte concentration, the initial fluoride concentration, initial pH and the current density were evaluated to find out their impact on the process and to define optimum treatment conditions.
- THAN Q