The precipitation of phosphorus from wastewater through pH variation in the presence and absence of coagulants

Potential of cyanobacterial biofilms in phosphate removal and biomass production

“…It has often been observed that the pH of the culture medium increases during the growth of photosynthetic organisms. This rise in pH has been implicated in precipitation of phosphate due to formation of hydroxyapatite (Diamadopoulos and Benedek, 1984). High pHeinduced phosphate precipitation contributed as much as 57% to the total phosphate removal by Phormidium bohneri from wastewater (Lalibert e et al, 1997).…”

Evaluation of Microalgae for Secondary and Tertiary Wastewater Treatment

“…Elevated pH has many impacts on wastewater treatment. It causes phosphorus precipitation through the formation of hydroxyapatite (Diamadopoulos and Benedek, 1984), helps to improve flocculation of particles and also disinfect pathogenic organisms as well. Nitrogen is an essential nutrient required by microalgae cells.…”

“…Elevated pH levels may have different effects on wastewater treatment. High pH causes phosphorus precipitation through the formation of hydroxyapatite (Diamadopoulos and Benedek, 1984), helps to improve flocculation of sludge and the subsequent harvesting process (Borowitzka, 1998) and helps to reduce coliform bacteria (Polprasert et al, 1983).…”

Electrochemical phosphorus removal and recovery

“…However, to achieve efficient precipitation, the wastewater pH needs to be raised above 10 [89,124]. The most simple way of increasing wastewater pH is by adding sodium hydroxide [28,65].…”

“…Conventionally, calcium phosphate precipitation in wastewaters can be achieved at increased pH (>9) and/or increased concentration of calcium ions [124]. In this approach, however, calcium and phosphate ions precipitate as sludge and have inadequate settling performance [150].…”