Recent advances in removing phosphorus from wastewater and its future use as fertilizer (1997–2003)

• Published in: Water research (Oxford) Vol. 38; no. 19; pp. 4222 - 4246
• Main Authors: de-Bashan, Luz E., Bashan, Yoav
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.11.2004; Elsevier Science
• Subjects: Applied sciences; Biological and medical sciences; Biotechnology; Chemical Precipitation; Conservation of Natural Resources; Durapatite - chemistry; Enhanced biological phosphorus removal; Environment and pollution; Eutrophication; Exact sciences and technology; Fertilizers; Fundamental and applied biological sciences. Psychology; Hemostatics - chemistry; Industrial applications and implications. Economical aspects; Magnesium Compounds - chemistry; Other industrial wastes. Sewage sludge; Phosphate precipitation; Phosphate-accumulating organisms; Phosphates - chemistry; Phosphorus - isolation & purification; Phosphorus removal; Pollution; Struvite; Waste Disposal, Fluid - methods; Wastes; Water Pollutants - isolation & purification; Water treatment; Water treatment and pollution; Wetlands; South Africa, Free State; Water treatment; PSF; Phosphate-accumulating organisms; MGPB; PHA; EPS; PHB; Struvite; EDTA; PGPB; Wetlands; Phosphorus removal; Enhanced biological phosphorus removal; COD; Phosphate precipitation; PSB; EBPR; 3-HV; PAO; Phosphates; Activated sludge; Ammonium; Fresh water; Hydroxyapatite; Waste water; Biological purification; Eutrophication; Agriculture; Wetland; Seawater; Fertilization; Chemical precipitation; Phosphorus; Fertilizers; Adsorption; Artificial medium; Surface water; Water pollution; Waste water purification
• ISSN: 0043-1354; 1879-2448
• DOI: 10.1016/j.watres.2004.07.014

Large quantities of phosphate present in wastewater is one of the main causes of eutrophication that negatively affects many natural water bodies, both fresh water and marine. It is desirable that water treatment facilities remove phosphorus from the wastewater before they are returned to the environment. Total removal or at least a significant reduction of phosphorus is obligatory, if not always fulfilled, in most countries. This comprehensive review summarizes the current status in phosphorus-removal technologies from the most common approaches, like metal precipitation, constructed wetland systems, adsorption by various microorganisms either in a free state or immobilized in polysaccharide gels, to enhanced biological phosphorus removal using activated sludge systems, and several innovative engineering solutions. As chemical precipitation renders the precipitates difficult, if not impossible, to recycle in an economical industrial manner, biological removal opens opportunities for recovering most of the phosphorus and beneficial applications of the product. This review includes the options of struvite (ammonium-magnesium-phosphate) and hydroxyapatite formation and other feasible options using, the now largely regarded contaminant, phosphorus in wastewater, as a raw material for the fertilizer industry. Besides updating our knowledge, this review critically evaluates the advantage and difficulties behind each treatment and indicates some of the most relevant open questions for future research.