The production process of the agro-food industry is aimed to ensure consumer’s solvency and satisfaction. As a result, these industries are accelerating their pace and rate of production by resorting to the intensive use of natural resources, especially water and energy. This production rate is accompanied by an increase in the volume of wastewater. According to the normative and legal requirements governing the protection of environment, this wastewater requires characterization in order to guide the choice of their treatment system and recovery. This paper focuses on the physicochemical characteristics of sugar agro-food industry wastewater (Cosumar-Morocco) in order to guide the choice of their appropriate treatment, allowing the reduction of their impacts and nuisances on the marine receiving environment or their reuse. The results obtained, following a follow-up of 4 months (March, April, May and June 2015), revealed that the industrial wastewater of Cosumar is relatively warm and basic with average values of temperature and pH respectively equal to 42, 71 ° C (± 2.61) and 9.38 (± 1.64). These liquid effluents also exhibit a high charge of oxidable matter (average COD=4801.33 mg.l-1 (±2342.66), organic matter (BOD5=3959.01 mg.l-1 ±2293.65), and particulate matter (average solids content = 275, 5mg.l-1±143.25). Moreover, the raw wastewater presents a strong mineralization, which is justified by an Electrical Conductivity of 6828.33 μs.cm-1 (±1704.44) and a Sulphate content of 94.33 mg.l-1 (± 31.66). The average concentrations of Kjeldahl Nitrogen and total Phosphorus are 6.5 mg.l-1 (± 2.54) and 0.67 mg.l-1 (±0.562) respectively. The COD/BOD5 ratio is 1.21, indicating the biodegradability of the wastewater produced, through which the biological treatment can be recommended.

The study aimed to evaluate the spatiotemporal variation in the physico-chemical and bacteriological quality of Oued Inaouène water in relation to urban discharges that remain the main sources of pollution in the Inaouene basin. During the period from May 2019 to March 2020, seven stations were sampled, six of which are spread along the Inaouène Oued in addition to one reference station that is less affected by urban pollution. The indicators used were: temperature, pH, electrical conductivity (EC), turbidity and dissolved oxygen (OD), biological oxygen demand (BOD 5 ), chemical oxygen demand (COD), Kjeldahl nitrogen (TKN), E coli, IE and TC. The quality data obtained were analysed using multivariate statistical methods (the CPA) and the correlation matrix. The results showed that with the exception of the O T station located upstream of urban discharges, the majority of stations downstream of urban discharges have poor quality during both wet and dry seasons, according to the Moroccan standards.

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Oued Nfifikh is a coastal stream of the Bouregreg and Chaouia watershed (Morocco). It passes through many rural and urban areas and receives different types of liquid and solid discharges from anthropogenic activities adopted along the watercourse. This study aims to evaluate the physicochemical quality of the water from the most accessible sites upstream and downstream of Oued Nfifikh, along with highlighting the impact of human activities on these waters' quality. For this purpose, water samples were collected and analyzed within normalized methods. Statistical analysis of the collected data shows significant spatial variations (p value < 0.05) for pH, electrical conductivity, nitrate and chloride, and for metallic trace elements (Zn, Fe, Ba, Mn, Cr and Al). Unlike (temperature, Pb, Ni, Cu and Cd), whose values do not present statistically significant variations (p value > 0.05). The study of the physicochemical quality reveals that the waters at the upstream are classed as good quality, except for site (S2), located at the upstream part of the river, it is affected by human activities. Consequently, its physicochemical composition is quite similar to that of waters of poor quality at the downstream sites. The Principal Component Analysis of the results followed by the Ascending Hierarchical Classification on the same data matrix allowed to regroup the sampling sites with similar characteristics into three distinct groups. A group of highly mineralized waters, a second group dominated by elements indicating urban pollution, and a group of waters with low mineral content and low metallic contamination indicating agricultural pollution.

Effluents from the surface treatment industry often have a high load o f highly toxic chemicals that need to be treated in accordance with increasing ly stringent regulations. In this work, we performed a characterization of liqu id effluents from a surface treatment unit in Morocco that revealed high collo idal pollution (Turbidity=131 NTU), high stainless material (COD=960 mg/l ) and metal elements (Iron, copper, zinc, nickel, aluminum, chromium and cy anide). The objective of this experimental study is to apply a physico-chemical treatment by coagulation-flocculation to these toxic industrial wastewater in order to comply with the discharge standards in the local sewage system. This treatment, preceded by pH adjustment, cyanide oxidation and reduction of hexavalent chromium, resulted in a very satisfactory reduction in toxicity of these effluents with abatement rates of 94% for COD and up to 99% for turbidity and metal load.