Fluoride Removal

High concentrations of natural fluorides are of significance in some regions of the United States including New Mexico, West Texas, Colorado, Indiana and Illinois. Additionally, fluorides are a waste product in association with glass manufacturing, electroplating, and the production of steel and aluminum, pesticides, fertilizer and semiconductor manufacturing. The maximum contaminant level for fluoride established by the Environmental Protection Agency is established at 4 parts per million, with a secondary standard set at 2 parts per million. Removal of fluoride from municipal and industrial waste water may be obtained by precipitation, as well as membrane and adsorption processes. The best way, bar none, to reduce the concentration of fluoride to 1 part per million or less is through adsorption onto specially designed wide pore size activated alumina.

DAI provides pretreated activated alumina (Dyna-Aqua™ Fluoride) designed to address commercial and industrial needs reducing the concentration of fluoride in wastewater effluent and municipal water systems to less than 1 ppm. This specially designed wide pore activated alumina is cost competitive with any other form of purification and provides simplicity of design and ease of utility. This novel product is an exciting addition to the expanding line of custom designed activated alumina compounds offered to purify municipal and industrial wastewaters.

A key advantage in using activated alumina for fluoride removal is that fluoride extraction is in part dependent upon the pH of waste water contents. Because of its unique amphoteric properties activated alumina works optimally in a pH range of 5.5 to 8.5. If the effluent stream is extremely alkylotic the source waste water may need to be pretreated in order to reach a pH range of 5.5 to 6.5 to achieve peak fluoride removal efficiency. Furthermore there is no simpler means to remove fluoride than through the use of a column of adsorbent material containing specialized activated alumina. Flow rate efficiency is affected by particle size. The smaller the particle size, the higher the flow rate that can be used. This must be balanced against the higher pressure drop which results from smaller size material. Competitive adsorption may occur in the setting of high concentrations of bicarbonate ions. For this reason Dyna-Aqua™ Fluoride is of such high efficiency that even with competitive binding with bicarbonate ions the total effluent concentration of fluoride will remain less than 1%.

Dyna-Aqua™ Fluoride Product Info | A Re-Examination of the Role of Fluoride in Municipal Water Supplies