Integrated Physicochemical and Biological Treatment Process for Fluoride and Phosphorus Removal from Fertilizer Plant Wastewater

Abstract

The phosphate fertilizer industry produces highly hazardous and acidic wastewaters. This study was undertaken to develop an integrated approach for the treatment of wastewaters from the phosphate industry. Effluent samples were collected from a local phosphate fertilizer producer and were characterized hy their high tluoride and phosphate content. First, the samples were pretreated hy precipitation of phosphate and fluoride ions using hydrated lime. The resulting low-fluoride and phosphorus effluent was then treated with the enhanced biological phosphorus removal (EBPR) process to monitor the simultaneous removal of carbon, nitrogen, and phosphorus. Phosphorus removal included a twostage anaerobic/aerobic system operating under continuous flow. Pretreated wastewater was added to the activated sludge and operated for 160 days in the reactor. The operating strategy included increasing the organic loading rate (OLR) from 0.3 to 1.2 g chemical oxygen demand (COD)/L-d. The stable and high removal rates of COD, NH/-N, and P04''~-P were then recorded. The mean concentrations of the influent were approximately 3600 mg COD/L, 60 mg N/L, and 14 mg P/L, which corresponded to removal efficiencies of approximately 98%, 86%, and 92%, respectively. Water Environ. Res., 83, 731 (2011).

Evaluation of phosphate removal capacity of Fe3O4–ZVINPs from aqueous solution: optimization using response surface analysis

“…Chemical precipitation [4], adsorption [1], reverse osmosis [5], and biological removal [6] have been reported in literature for removal of PO 4 3-from wastewater. Of these, adsorption is a better method, because it is cost effective, highly efficient, and easy to apply for removal of various toxic chemical contaminants from water and wastewater [7][8][9].…”

Effect of TiO2, Al2O3, and Fe3O4 nanoparticles on phosphorus removal from aqueous solution

“…However, immobilization and/or control of nonpoint P in the surrounding soils for a water body remain a challenging environmental issue . Chemical precipitation , physicochemical processes , and enhanced biological P removal are the frequently used techniques to remove P. Phosphorus can be removed from water using sorbents such as oxides of iron, natural ores like calcite, goethite, active red mud, and activated carbon . One of the problems encountered with these sorbents is that they have very low sorption capacities.…”

Enhanced Adsorption of Fluoride from Aqueous Solution Using an Iron‐Modified Attapulgite Adsorbent

“…The Chinese drinking water standard has been amended to lower fluoride content in drinking water to less than 1.0 mg/L. Fluoride pollution in the environment can occur as a result of natural events and human activities (Fan et al, 2003;Gouider et al, 2011;Hua et al, 2009). Fluoride frequently exists in minerals, and it can be leached out as a result of erosion by rainwater, thereby allowing it to contaminate groundwater and surface water.…”