Characterization and evaluation of the treated water quality from the wastewater treatment plant of the Djelfa city

In the framework of the protection of the environment, we proceeded during the year 2016 (12 months), to the follow-up of variation of the wastewater pollution parameters at the inlet and at the outlet of the treatment plant of the Djelfa city, which operates by activated sludge, following the medium load process.The physicochemical analyzes were carried out on the following parameters: pH, temperature, eclectic conductivity, turbidity, Total suspended solids, COD, BOD5, NH4+, NO3- and total phosphorus. At the end of these analyses, we obtained good elimination yield of 92% to 91% for TSS and 92% to 91% for BOD5. The COD recorded a reduction of 84% to 83%. Total phosphorus achieved a removal efficiency of 55% to 66%. For nitrogen, Ammonia experienced a 61% to 57% reduction from inlet to outlet of the plant. On the other hand, nitrates recorded an increase of 200% to 236%, due to nitrification.The quality of the treated water, for the majority of the parameters, complies with the standards required by Algerian regulations and those of the WHO. We can conclude that the treatment system adopted at the level of the WWTP of Djelfa is effective and justified its design and its objective of realization.