ETUDE COMPARATIVE DE DEUX TECHNIQUES D’EPURATION DES EAUX USEES SOUS UN MILIEU ARIDE (LAGUNAGE AERE ET PHYTO-EPURATION) CAS DE LA WILAYA DE OUARGLA

Abstract

The present study consists in analyzing quality of wastewater (before and after treatment) of two treatment stations: the first one is installed in Temacine and uses treatment by standing bed of plants and the second one is installed in Said Otba and uses treatment by aerated lagoon. Analyses of different parameters were done at the laboratory of each station. To facilitate the study of the results, we used the seasonal averages of every parameter. Results showed efficiency of both processes but with an advantage for the process of treatment by standing bed of plants. The values registered in this process go with Algerian standards compared to those obtained by process of treatment by aerated lagoon. The most important parameter, which showed the efficiency of both processes, was elimination of suspended solids (SS). The elimination of SS in the station of treatment by standing bed of plants and in the station of treatment by lagoon were successively 93,84 % and 92,82%. For COD, rates of efficiency were: (i) from 82,580 % to 90,288 % for standing bed of plants process and (ii) from 71,848 % to 80,864 % for lagoon process. Concerning BOD5, the maximal rate of elimination (93,898 %) was registered in the station of treatment by standing bed of plants