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Marrakesh, Morocco

Neffa M.,Laboratory of Chemistry Bioorganic and Macromolecular LCBM | Hanine H.,Sultan Moulay Slimane University | Lekhlif B.,Center Detudes Et Of Recherches En Ressources En Eau Cerhydreau | Ouazzani N.,Laboratory of Hydrobiology | Taourirte M.,Laboratory of Chemistry Bioorganic and Macromolecular LCBM
Desalination and Water Treatment | Year: 2014

Olive mill wastewaters (OMWW) are a significant source of potential or existing environmental pollution in the Mediterranean countries. Treatment and reuse of OMWW present significant challenges, both due to the nature of olive oil production (seasonal and concentration in a small scale) and due to the characteristics of the wastewater (high chemical oxygen demand (COD) and high phenolic content). In the present work, experiments of different pretreatment methods were undertaken and compared in order to select the most adequate process to be applied before biological treatment of OMWW. In fact, three different pretreatments were tested and compared: two different coagulants (alginate and Kim2120) and electrocoagulation (EC) process. At the second stage, biological treatment (using white-rot fungus) was investigated. Tests were conducted with raw OMWW and with OMWW diluted in 50% tap water and adjusted to a neutral pH with lime. The raw effluent presents high COD (178 g O2 l-1), about 6.4 g l-1 of total suspended solids (TSS), a high conductivity (29 mS cm-1), acidic pH 4.8, and turbidity of 90 NTU. Results show that after 90 min of EC process, using 15 V/m2 voltage, a maximum of 49% of organic matter removals was achieved. The optimum removals of COD and turbidity obtained were 39 and 75%, respectively when 20 mg l-1 dose of alginate is used, especially at pH 7. Coagulation using Kim2120 at 10 mg l-1 applied on diluted OMWW showed reduction reaching 52.3% of COD and 85% of turbidity. The maximum removal of total polyphenols, tyrosol and hydroxytyrosol obtained were 60.1, 23.1, and 59.1% with lime/alginate and 64.2, 67.8, and 76.3% with lime/kim2120, respectively. Only 57% of polyphenols was removed by EC. The pretreated effluents by different physicochemical processes tested showed that the best yields were obtained with lime/kim2120. The pretreated olive mill wastewater was then treated aerobically with white-rot fungus. The results showed that the white-rot fungus was capable of reducing 68% and 75% of COD, respectively for the diluted OMWW and pretreated by lime or lime/Kim2120, after only 5 days of growth. The best biological treatment was obtained with neutral pH. © 2013 Balaban Desalination Publications. All rights reserved. Source

Baroud S.,Universite Ibn Tofail | Belghyti D.,Universite Ibn Tofail | Aziz F.,Cadi Ayyad University | Aziz F.,Laboratory of Hydrobiology | And 2 more authors.
Journal of Materials and Environmental Science | Year: 2015

The present study aimed to characterize raw wastewater of Khenifra city (Morocco), to evaluate pollution in relation to the demographic and socio-economic profiles of the population connected to the network sanitation, and interpreting the results with the contribution of ACP. The physico-chemical characterization of raw wastewater revealed that liquid effluents are loaded with organic matter in terms of COD (COD average = 556.02 mg/L) whether a load of 3373.94 kg/day, a BOD5 (Avg. = 284.55 mg/L) with a load of about 1731.20 kg /day. TSS (Avg. = 239.20 mg/L) whether a load of about 1457.04 kg/day, and mineral expressed in terms of electrical conductivity (Avg. = 1801.61 μS/cm) with a pH of 8.13. The mean levels of total phosphorus and TKN are of the order of 94.07 mg/L and 12.17 mg/L, respectively. Although these wastewater has a high organic load (BOD5 /COD = 0.51 and MES/BOD5 = 0.85) they have satisfactory biodegradability. The exam of ratio COD/BOD5 = 2.00 highlights the good biodegradability which biological treatment seems entirely appropriate. Statistical analysis of the results by principal component analysis (PCA) performed on 56 individuals and 9 variables (Flow rate, Temperature, EC, TSS, TKN, TP, COD, BOD5) show the existence of a strong positive and significant correlation between the TSS, BOD5, COD and electrical conductivity. The factorial plan F1, axis of pollution, represents 42.44% of the variance. The second plan F2 represents only 25.24%. Source

El Fadeli S.,Laboratory of Hydrobiology | El Fadeli S.,ETH Zurich | Bouhouch R.,ETH Zurich | Chaik M.,Laboratory of Hydrobiology | And 6 more authors.
Journal of Materials and Environmental Science | Year: 2014

The aim of this study is to investigate lead contamination in food chain and evaluate the consequent health risks to local residents in three different sites in the Marrakech urban area, compared to a rural reference region far from any source of lead contamination. The following three urban sites that have been selected to have different potential routes of lead exposure: a) old unimproved water pipes (the Medina); b) agricultural land irrigated from untreated urban wastewater (El Azzozia); and c) a mining site (Drâa Lesfer region) were considered in this study. Samples were collected from three compartments: drinking water, soils and plants (edible part). The levels of lead contamination in these compartments were measured. Transfer factors of lead from soils to plants and the eventual health risk of this metal were calculated. The results showed that lead concentration in drinking water of all sites was below the drinking water safety limit. However, soils and plants from mining site were heavily contaminated as compared to the other sites. Consequently, the oral intakes of lead from local plant foods may pose a high health risk to local residents in the mining site and in the wastewater irrigation sites. Source

El-Fadeli S.,Laboratory of Hydrobiology | Bouhouch S.,Laboratory of Human Ecology | Skalny A.V.,Yaroslavl State University | Barkouch Y.,Regional Laboratory of Epidemiological Diagnosis and Environmental Health | And 3 more authors.
Biological Trace Element Research | Year: 2016

The major environmental factor that determines goiter prevalence is iodine status. However, other trace elements like selenium and zinc can influence the thyroid function. Hair samples (n = 68) were collected from goitrous and non-goitrous children aged 8–12 years living in the area of Al Haouz Marrakech-(Morocco). Trace element concentrations (Cr, Fe, Mg, Zn, Se, I) in hair were measured using flame atomic absorption spectroscopy, graphite furnace atomic absorption spectroscopy, and inductively coupled plasma mass spectrometry. Difference in the mean concentration of each trace element between groups was determined by ANOVA test. The mean concentration levels of I, Se, and Zn for goitrous children were lower and were similar to the mean concentrations reported in the literature for subjects with goiter. The regression results gave us a better model that revealed significant positive relations between thyroid volume and Zn contents and significant negative relation with I and Se. The overall findings of the present study revealed that the actual factors of thyroid gland volume increase are I and Se deficiency. This work could shed some light on the effects of trace elements—other than iodine—on the thyroid disorders. © 2015, Springer Science+Business Media New York. Source

Latrach L.,Cadi Ayyad University | Latrach L.,Laboratory of Hydrobiology | Ouazzani N.,Cadi Ayyad University | Ouazzani N.,Laboratory of Hydrobiology | And 6 more authors.
Ecological Engineering | Year: 2016

This study aims to present the removal of bacterial indicators of fecal contamination and parasites in a combined treatment using a multi-soil-layering system with sand filters (MSL-SF). This experiment was carried out in a laboratory scale. The MSL pilot (height 65 cm, width 36 cm, depth 30 cm) was composed of soil mixture layers (SML) and gravel layers that are arranged in a brick-layer like pattern. The soil mixture layers are composed of local sandy soil mixed with sawdust, metal iron and charcoal at the ratio of 70, 10, 10 and 10%, respectively, on a dry weight basis. The applied hydraulic loading rate (HLR) was 200 L m-2 day-1. The experimental sand filter included three parallel similar sand columns (inside diameter 12.5 cm, height 120 cm). Each column was filled with 80 cm of fine sand and 10 cm of gravel in the top and the bottom of the filter. Three sand columns HLRs (100, 200 and 400 L m-2 day-1) were compared. The obtained results indicated that the conceptual model based on the combination of the MSL method and sand filter (MSL-SF) showed very high efficiency in organic matter, nutrients, bacteria and the reduction of parasites. The high performances were noted in the low HLR. The main removal percentage of SS, BOD5, COD, TN and TP were respectively 99.73, 97.78, 98.40, 92.93 and 96.21% for the HLR-100. In addition, the Log10 removal for total coliforms, fecal coliforms and fecal streptococci were 4.46, 4.47 and 4.13 Log unit respectively. MSL-SF is capable of removing 100% of helminthes eggs. The MSL system is an efficient method, especially for organic matter and nutrients (N, P) removal. Sand filters have experimentally been proved to be useful for fecal indicators and the removal of parasites. Good operational stability and high contaminants removal efficiency of the combined systems were observed. Therefore, the combination of the MSL system and sand filter offer a good alternative option for agricultural wastewater reuse. © 2016 Elsevier B.V. Source

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