Volume 2 Issue 11
Authors: P. K. Sarkar; A. G. Hegde; P. M. Ravi; M. Gadhia; M. K. Jha; A. K. Patra
Abstract: Eleven physico-chemical and three radiological parameters were studied in eight different sampling locations from upstream and downstream of Tapi river water due to the operation of the Pressurised Heavy Water Reactor (PHWR) located at Kakrapar. Different multivariate statistical techniques such as Cluster Analysis (CA), Factor Analysis (FA)/ Principal Component Analysis (PCA) were applied for evaluation of temporal/spatial variations of water quality data obtained during 2007-2009. The PCA of the four data sets evolved three PCs each for all the regions with eigen value > 1, explaining 57.4, 62.5, 55.7 and 70.0% of the total variance in respective water quality data sets. CA of grouping all the eight sampling locations on the aquatic system into three statistically significant clusters at (Dlink/Dmax) x 100 < 70. CA technique was found to be useful in offering a reliable classification of the surface water. No significant seasonal variations were observed except temperature. The results of physico-chemical parameters were well within the Central Pollution Control Board (CPCB), India prescribed limits. The radioactivity levels of 137Cs, 90Sr and 3 H activity were also well within the prescribed technical specification limit by Atomic Energy Regulatory Board (AERB), India. The present study demonstrated the insignificant impact on aquatic environment due to operation of Kakrapar Atomic Power Station
Keywords: KAPS; Physico-Chemical Parameters; Radiological Parameters; Tapi River
Authors: Ammar H. Al-Dujaili; Akl M. Awwad; Nida' M. Salem
Abstract: The present study investigated the effectiveness of an inexpensive and eco-friendly loquat bark as a biosorbent for the possible removal of toxic lead, zinc, and cadmium ions from aqueous solutions. In this study, the effects of biosorbent dose, pH, initial concentration, contact time, and temperature were examined. The linear Langmuir and Freundlich models were applied to describe the equilibrium isotherms, and both models fitted well. The monolayer adsorption capacity of of Pb(II), Zn(II) and Cd(II) on loquat bark was found as 55.770, 29.447 and 28.802 mg g-1, respectively, at pH 4 and 30oC. Dubinin-Radush Kerich (D-R) isotherm model was also applied to equilibrium data. The mean free energy of adsorption of Pb(II), Zn(II) and Cd(II) (5.596, 3.748 and 3.549 kJ/mol) onto loquat bark, respectively, may be carried out via physisorption mechanism. Loquat bark (LB) was found to remove Pb(II), Zn(II), and Cd(II) ions efficiently from aqueous solutions with selectivity in the order of Pb(II) > Zn(II) > Cd(II).
Keywords: Keywords: Metal ions, biosorption, loquat bark, isotherms
Authors: Jianfeng Liang; Jieying Huang; Xiaochun Xu; Liwei Chen
Abstract: The environmental effects of heavy metals in waste rocks, soils, sediments and waters by metalliferous mining activities in Tongling were studied. In this study, samples collected from waste rocks, soils, sediments and water of Xiangsi River were analyzed. The heavy metal contents increased along the middle area of the river valley. The maximum contents of the heavy metals in the area were higher than the background value and the quality standard value of environment due to the acid mine drainage (AMD) generated by the waste rocks, indicating the potential mining activities of causing environmental problems.
Keywords: Environmental Effects; Xiangsi River; Acid Mine Drainage (AMD)
Authors: J.L. Regens; E.I. Kurbatova; A.I. Ksenofontov
Abstract: This research illustrates the application of a combination of computer modeling and laboratory experiments to designing nanoscale structural surface layers of compositions for remediating radiologically contaminated soil and water. Natural sorbents and sorption materials with nanoscale structured surface layers of various structures are compared in terms of sorption efficiencies. Monte Carlo simulation to generate numerical calculations and chemical and physical analyses to verify the modeling predictions of the structure of metallic surface zones synthesized by ionic beams was performed. Fe, Al, and Al2O3 compositions were irradiated with Ti ions to form nanoscale structured surface layers of various structures. 90Sr and 137Cs were used in the laboratory experiments to assess sorbent performance. The results demonstrate that using the sorbents with new structural forms of a surface produces increased efficiency in potential radionuclide sorption.
Keywords: Ionizing Fluxes; Radiation Factor; Materials Science; Modeling; Natural Sorbents; Nano Structured Surfaces; Synthesized Compositions; Soil Solutions
Authors: Rosemary I. Egonmwan; Nnamdi H. Amaeze; Adebayo A. Otitoloju; Adedamola F. Jolaoso
Abstract: The physical and chemical characteristics as well as the fish species diversity of the coastal fishing grounds of the Lagos lagoon were assessed over a twelve month period. The sampling area was divided into four Zones in line with the established salinity regimes in the area. The sources of pollution in the coast line were found to be widely varied, ranging from chemical inputs and sewage to solid waste. These have caused far reaching effects ranging from foul odour, loss of aesthetics and deterioration in the water quality to reduced fish catch. Overall fish catch was higher in areas closer to river inputs into the lagoon (Zone I and II) where the pollution input was mainly from sewage and diluted effluents. Unregulated burning of sawdust at Okobaba and oil pollution at the ports has led to depleted fish catch in Zones III and IV respectively. Chemical characteristics of the water often fell within the FEPA set limit and there was strong correlation each between chemical oxygen demand (COD), salinity and electrical conductivity of the surface water. Fish diversity significantly varied with sampling Zones (p<0.05) and generally areas receiving organic waste had higher fish diversity compared to those receiving chemical waste.
Keywords: Waste; Coastal Pollution; Physicochemical Characteristics; Lagos Lagoon; Fish Diversity
Authors: M.A. Correa-Murrieta; J.A. Núñez-Gastélum; R.G. Sánchez-Duarte; J.R. Rodríguez-Núñez; D.I. Sánchez-Machado; J. López-Cervantes
Abstract: Moringa oleifera is a plant whose seeds have protein or polypeptide with coagulant properties. The present study evaluated the effect of Moringa oleifera seed (MOS) extract as primary coagulant and its mixture with aluminum sulfate in the treating of superficial waters with turbidities between 72 and 118 NTU obtained from Náinari lagoon located in Northwestern México. An average of 88.9% turbidity removal was achieved when MOS extract was used as primary coagulant with a dosage of 250 mg/l. In combination with aluminum sulfate reached 96.5% of clarification, and moreover is obtained saving 66% of chemical coagulant. The MOS extract is a viable alternative to diminish the use of chemical coagulants in the clarification of surface waters.
Keywords: Coagulants; Wastewater; Polypeptide; Water Treatment; Turbidity