Elimination du carbone organique biodegradable par les procedes de traitement biologique sur les filieres de productions d'eau potable

Abstract

Abstract Evolution of biodegradable dissolved organic carbon (BDOC) was studied on two surface water treatment: plants including for the first one rapid and slow sand filtration followed by ozonation and for the second one preozonation, contact coagulation on rapid sand filters, slow sand filtration, ozonation and GAC filtration. It appears that about 37 % of the raw water organic matter is biodegradable. An average of 81 % of this BDOC is removed by rapid sand filtration followed by slow sand filtration. For the second treatment plant, preozonation at an ozone rate of 1 ppm increased raw water BDOC by about 28,5 %. But contact coagulation and slow sand filtration removed 74,5 % of this BDOC. For the two treatment plants, waters after slow sand filtration have presented a great biological stability (BDOC less than 0,5 ppm and less than 15 % of DOC). Ozone disinfection at an ozone rate of 0,3 ppm also increased biodegradability filtration about 85 % of the BDOC is removed. Only 55 % on the BDOC is removed ...