PREDICTION THE EFFICIENCY OF CHEMICAL PRECIPITATION AND COAGULATION FOR MERCURY REMOVAL FROM WASTEWATER

Abstract

Mercury is one of contaminating elements for environment being a heavy metal that discharged from many chemical industries, such as Al- Furat State Company for Chemical Industries, where it is used as a catalyst in mercury cells to produce caustic soda NaOH, leading to the introduction of some concentrations of mercury with wastewater discharged from the process plant.The presence of toxic heavy metals in industrial discharge wastewater has become a matter of environmental concern and certainly, these metals have negative side effects on humans and on aquatic ecosystems.The outcomes of this research showed that the most effective conditions for the efficient removal of mercury from wastewater by using of precipitation and coagulation method are within, pH range (7-8), and ambient temperatures with 1 hour resident time for each precipitation and coagulation processes. The approach of treatment includes only one filtration process at the end of coagulation process.The dosage of Na2S (the precipitated material) has an effective role for the treatment process, which is characterized as inexpensive and easy.According to the presented results, an efficiency of (99%) for mercury removing can be achieved by this method