title: Chemical behavior of different species of phosphorus in coagulation.
abstract: Phosphorus is one of the elements that have a significant impact on such environmental problems as eutrophication or algal bloom. Phosphorus compounds in water can be hydrolyzed to orthophosphate that is the only form of phosphorus that algae can assimilate. In this study, phosphorus removal in terms of orthophosphate and total phosphorus from wastewater was studied using alum or ferric ions as coagulants. It was observed that alum shows higher phosphorus removal efficiency than ferric ions in the same mole ratio concentrations. The proportion of orthophosphate among total phosphorus did not change significantly during coagulation process when the coagulant concentration is low. However, the proportion becomes gradually decreased as the coagulant concentration increases. Not only the electrolyte concentration difference in solution, but the characteristics of orthophosphate and polyphosphate such as reactivity and ionic size might also cause the differences in the removal rate. Orthophosphate that has greater reactivity than other phosphorus species would be involved in chemical reactions dominantly when large amounts of coagulants are applied. However, the effect of reactivity was diminished due to the large ionic size of polyphosphate and low concentration of electrolyte in low coagulant concentration during the coagulation process.
authors.affiliation: Department of Energy Systems Engineering, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul, 151-744, Republic of Korea.
authors.forename: Taejun
authors.initials: T
authors.lastname: Park
authors.affiliation: Department of Energy Systems Engineering, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul, 151-744, Republic of Korea.
authors.forename: Vanvimol
authors.initials: V
authors.lastname: Ampunan
authors.affiliation: Center for Water Resource Cycle Research, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul, 136-791, Republic of Korea.
authors.forename: Sanghyup
authors.initials: S
authors.lastname: Lee
authors.affiliation: Department of Energy Systems Engineering, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul, 151-744, Republic of Korea. Electronic address: echung@snu.ac.kr.
authors.forename: Eunhyea
authors.initials: E
authors.lastname: Chung
mesh_terms: D000534:Alum Compounds / Q000737:chemistry; D005068:Eutrophication; D005427:Flocculation; D006868:Hydrolysis; D008962:Models, Theoretical; D010710:Phosphates / Q000737:chemistry / Q000302:isolation & purification; D010758:Phosphorus / Q000737:chemistry / Q000302:isolation & purification*; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*
chemical_list: D000534:Alum Compounds; D010710:Phosphates; D010758:Phosphorus; D062065:Wastewater; D014874:Water Pollutants, Chemical; C041524:aluminum sulfate
keywords: Coagulation; Orthophosphate; Phosphorus removal; Polyphosphate; Wastewater treatment