20 research outputs found
Application Of Multivariate Statistical Methods To Surface Water And Groundwater Of The Soummam Basin, Algeria
Multivariate statistical methods, i.e., cluster analysis (CA), discriminant analysis (DA) and analysis of variance (ANOVA), were used to assess spatial variation in the water quality of the Soummam basin, Algeria. The application of hierarchical cluster analysis, based on all possible combinations of classification method, showed three main groups of samples. The group 1 samples are exclusively composed of surface water. Groups 2 and 3 samples are consisted of groundwater. Discriminant analysis (DA) was assigned about 98.6% of the cases grouped by CA. All groups are super-saturation with Ca-montmorillonite, dolomite, gibbsite, K-mica, kaolinite and quartz, and all these groups are under-saturation with albite, anhydrite, anorthite, CO2(g), gypsum, halite, melanterite and smithsonite. The ANOVA results indicate that the saturation indices of each of the mineral phases are significantly except chalcedony and quartz (p \u3e 0.05)
Assessment of Heavy Metals Contamination in Groundwater: A Case Study of the South of Setif Area, East Algeria
Heavy metals in groundwater were analyzed and their sources and impacts were identified using multivariate statistical tools and risk assessment. Three significant factors were extracted by factor analysis (FA), explaining 75.69% of total variance. These factors were in turn described by the clusters C3, C2 and C1, respectively, resulting from the cluster analysis (CA). Factor analysis and cluster analysis revealed significant anthropogenic contributions and water-rock interaction effects of the metals in groundwater. The mean values of heavy metal evaluation index (HEI) and degree of contamination (Cdeg) indices indicated that the groundwater samples were contaminated with high degree of pollution by cadmium (Cd) and lead (Pb). The hazard quotients (via ingestion) of Cd and Pb were found to be higher than the safe limits, posing threat to the consumers. However, no risk related to the dermal contact was associated with the measured metal levels
Monometal and competitive sorption of heavy metals in mine soils: Influence of mine soil characteristics
pas de DOI / http://www.researchgate.net/publication/236158313International audienceThe environmental and health effects of the contamination of soils by heavy metals depend on the ability of the soils to immobilize these contaminants. This study was conducted to assess the monometallic and competitive sorption of lead, copper, zinc and cadmiumin surface samples of four soils from eastern Algeria. Sorption isotherms were characterized using Freundlich and Langmuir equations. Retention selectivity sequences indicate that, inmost of the soils, Pb is the preferred retainedmetal, followed by Cu. The last metals in these sequences are Cd and Zn.All soils showed greater sorption capacity. On the basis of distribution coefficient values for the metal concentration of 100 mg. l-1 (Kd100) for each soil and trace element, the two most common adsorption sequences found were Pb>>Cu>Cd>Zn and Pb>>Cu>Zn>Cd. Competition significantly reduced metal Kd, especially that of Cd
Suitability and Assessment of Surface Water for Irrigation Purpose
Surface water is an important resource that can create tensions between different countries sharing the same water sources to know that the agriculture is considered as the last sector that exploits less water compared to the industry which uses very large water quantities. The future strategies of agricultural development in the most of these countries depend on the ability to maintain, improve and expand irrigated agriculture. In this light, this chapter is written in the way to show some steps of the evaluation of surface water for irrigation purpose. The results obtained from this research make it possible to evaluate the suitability of surface water for irrigation and to draw useful recommendations for dam managers and farmers
Adsorption of Pb(II) from aqueous solutions using activated carbon developed from Apricot stone
International audienceLow-cost activated carbon was prepared from Apricot stone material by chemical activation with sulphuric acid for the adsorption of Pb(II) from dilute aqueous solution. The activated carbon developed shows substantial capacity to adsorb Pb(II) from dilute aqueous solutions. The parameters studied include physical and chemical properties of adsorbent, pH, adsorbent dose, contact time and initial concentrations. The percent removal increased with pH from 1.5 to 5. The optimum pH required for maximum adsorption was found to be 6.0. Adsorption kinetics data were modeled using the pseudo-first and pseudo-second-order models. The results indicate that the second-order model best describes adsorption kinetic data. The isotherm equilibrium data were well fitted by the Langmuir and Freundlich models. The estimatedmaximum capacities of lead ions adsorbed by Apricot stone activated with sulphuric acid were 21.38 mg gâ1. The adsorbent derived from this material is expected to be an economical product for metal ion remediation from water and wastewate
Removal of Pb2+ and Zn2+ from the aqueous solutions by activated carbon prepared from Dates stone
International audienceThe low-cost activated carbon prepared from Date stone, an agricultural solid waste by-product, were prepared by chemical activation with sulphuric acid for the removal of lead and zinc from aqueous solutions has been studied as a function of pH, contact time, metal concentrations and adsorbent concentrations. Adsorption equilibrium was reached after an equilibration time of 60 min and adsorption kinetics data were tested using Lagergren pseudo-first-order and pseudo-second order, the studies showed the adsorption process followed pseudo-second-order rate model. The maximum removal of Pb2+ and Zn2+ is observed at pH 6.0 (94.4%) and 7.0 (93.2%) respectively at initial concentration 20 mg/L. The isotherm equilibrium data were well fitted by the Langmuir and Freundlich models. The adsorption capacity q max) calculated from the Langmuir isotherm was 19.64 mg Pb2+/g and 10.41 mg Zn2+/g at an initial pH of 6.0 at 20 ± 2°C
Chemical associations and sorption capacity of Pb and Zn: Column experiments on a polluted soil from the Amizour mining district (Algeria)
International audienceThe column leaching behavior of lead and zinc is studied on a soil sample from the Amizour-Bejaia mining region, which is one of Algeria's largest natural reserves for Pb and Zn ores. The maximum amount of metal bound to the soil sample after column leaching by a mono-metal solution at pH 7 is 7.0 and 11.3 g/kg for Zn and Pb, respectively. These values exceed the maximum loading capacities derived from previous batch experiments conducted under similar conditions. The studied soil sample displays a stronger affinity for Pb than Zn under the study conditions. These two metals are associated with various chemical fractions of the mine soil sample, as revealed by a five-step, operationally-defined sequential chemical extraction procedure (with fractions categorized as: exchangeable, acid extractable, reducible, oxidizable, and residual) following column leaching. After metal addition and sorption, carbonates (i.e. the extractable fraction) and Fe- and/or Mn- (oxy)(hydr)oxide phases (reducible fraction) in the soil sample dominate for both Pb and Zn. The extractable fraction is mainly reserved for the purpose of zinc retention; moreover, the stabilization with Fe-Mn (oxy)(hydr)oxide phases serves as a major carrier for Pb
Modeling and optimization of process parameters in elucidating the adsorption mechanism of Gallic acid on activated carbon prepared from date stones
International audienceWe make use of chemical activation with phosphoric acid to prepare an activated carbon from date stones (DSAC). After characterization for surface area and pore volume, it was tested as an adsorbent for gallic acid (GA) removal from aqueous solutions Operating variables including contact time (410 min), adsorbent dosage (0.1 g in 150 mL), GA concentration (10 mg/L) and solution pH (4.5) were optimized using the Box-Behnken design (BBD) under response surface methodology (RSM) approach. Adsorption of GA onto DSAC may be described by the pseudo-second-order kinetics model equation suggesting that the process is chemisorption. The equilibrium data fitted the Langmuir isotherm model with a maximum capacity of 156 mg/g (25?C, pH 4.5). The GA adsorption process was found to be exothermic, while ?G? was negative implying that the reaction is spontaneous
Assessment of Surface Water Quality Using Water Quality Index and Discriminant Analysis Method
Given the complexity of water quality data sets, water resources pose a significant problem for global public order in terms of water quality protection and management. In this study, surface water quality for drinking and irrigation purposes was evaluated by calculating the Water Quality Index (WQI) and Irrigation Water Quality Index (IWQI) based on nine hydrochemical parameters. The discriminant analysis (DA) method was used to identify the variables that are most responsible for spatial differentiation. The results indicate that the surface water quality for drinking is of poor and very poor quality according to the WQI values, however, the IWQI values indicate that the water is acceptable for irrigation with restrictions for salinity sensitive plants. The discriminate analysis method identified pH, potassium, chloride, sulfate, and bicarbonate as the significant parameters that discriminate between the different stations and contribute to spatial variation of the surface water quality. The findings of this study provide valuable information for decision-makers to address the important problem of water quality management and protection
Assessment of Surface Water Quality Using Water Quality Index and Discriminant Analysis Method
Given the complexity of water quality data sets, water resources pose a significant problem for global public order in terms of water quality protection and management. In this study, surface water quality for drinking and irrigation purposes was evaluated by calculating the Water Quality Index (WQI) and Irrigation Water Quality Index (IWQI) based on nine hydrochemical parameters. The discriminant analysis (DA) method was used to identify the variables that are most responsible for spatial differentiation. The results indicate that the surface water quality for drinking is of poor and very poor quality according to the WQI values, however, the IWQI values indicate that the water is acceptable for irrigation with restrictions for salinity sensitive plants. The discriminate analysis method identified pH, potassium, chloride, sulfate, and bicarbonate as the significant parameters that discriminate between the different stations and contribute to spatial variation of the surface water quality. The findings of this study provide valuable information for decision-makers to address the important problem of water quality management and protection