Investigation of the Physico-Chemical Quality of the Wastewater in Fez City (Morocco) Using a Multivariate Statistical Method

Abstract

Similar to countries with arid and semi-arid climates, Morocco faces problems of degradation of the quality of its environment and more specifically the quality of groundwater. In this work, we approached the physico-chemical characterization of the raw effluents of three industrial units in Fez city, namely the textile industry (U 1 ), the copperware industry (U 2 ), olive oil industry (U 3 ) chosen for their degree of pollution and their environmental impact, the aim of which is to highlight the degree and nature of the pollution generated by these effluents, and their biodegradability during the winter period January to February of 2018, when the waste water treatment plant (WWTP) is malfunctioning. A set of samplings and measurements of different physico-chemical pollution parameters were carried out such as: temperature, pH, electrical conductivity, turbidity, salinity, chlorides, BOD 5 , COD, suspended solids (SS), Ca 2+ , K + , as well as heavy metals. The results show that the U 3 effluent is highly loaded in organic matter with high COD (37600 mg O 2 /L) and BOD 5 (13000 mg O 2 /L), while the U 2 effluent contains very high concentrations of heavy metals (Pb, Ni, Zn, Cu, Cd) 91,8, 71, 55,4, 53, 28 mg/L, respectively. on the other hand, the U 1 effluent is characterized by high SS contents, and concentrations of Ca 2+ , K + exceed Moroccan standards. The COD/BOD 5 ratio shows that U 1 and U 2 effluents are difficult to biodegrade even if their organic loads are low. In the light of these results, it is recommended that these discharges be pre-treated before they are discharged into the liquid sewer system.

The Impact of Wastewater on the Quality of Water of Nerodime River

“…The dumping of wastewater into surface water endangers the aquatic ecosystem by disrupting natural environmental conditions and exposing aquatic species living in that area to hazardous chemicals (Oyekanmi et al, 2021). The amount of biodegradable organic components that end up in receiving water bodies from inadequately treated wastewater effluents greatly increases the consumption of dissolved oxygen (Khanh & Nam 2022;Hasanawi & Salami 2022;El Ouadrhiri et al, 2022). As a result, as the concentration of dissolved oxygen declines, aquatic species' survival becomes challenging and perhaps dangerous.…”