Current Issue : July - September Volume : 2016 Issue Number : 3 Articles : 5 Articles
Groundwater contamination is a common occurrence the world over. When it occurs, it is very\ndifficult and expensive to overcome. Since groundwater is a major source of potable water and the\nmost widespread, it is very necessary to explore all avenues to avert its contamination. The impact that\ncontamination has on groundwater, its environment and consumers were discussed. These include\nhealth hazard, imbalance in the ecosystem, water scarcity, negative economy and inflation. The\nvarious steps to prevent groundwater contamination such as efficient waste disposal method, safe\nstorage and handling of hazardous materials and protection of chemicals or waste from floods and\nrainfall percolating underground were briefly discussed. Also discussed under prevention are good\nmanagement of waste products, monitoring of storage tanks and pipelines, well monitoring as well as\nformulation of an effective Water Policy. The solution to contamination are broadly grouped into two;\nnamely ex-situ and in-situ technologies. Some case studies were analyzed for future references...
On the basis of homogeneous liquid-liquid extraction (HoLLE) with Zonyl FSA to plating water\ncontaining 1 mg palladium, 96.6% of the palladium was extracted into the sedimented liquid\nphase. After phase separation, the volume ratio (Va/Vs) of the aqueous phase (Va) and the sedimented\nliquid phase (Vs) was 556 (50 mL ââ? â?? 0.09 mL). The assessment of the potential implementation\nof this procedure to wastewater treatment showed that HoLLE was satisfactorily achieved\nwhen the volume was scaled up to 1000 mL. Moreover, HoLLE was conducted to real palladium\nplating wastewater generated in the plating industry. 94.5% of the palladium was extracted into\nthe sedimented liquid phase. After phase separation, the volume ratio (Va/Vs) of the aqueous phase\n(Va) and the sedimented liquid phase (Vs) was 500 (50 mL ââ? â?? 0.1 mL). In addition, HoLLE could\nseparate palladium from coexisting metals in real plating wastewater. This knowledge is expected\nto lead to the development of new separation and concentration technologies of rare metals from\nreal plating wastewater....
The occurrence of antimicrobials in the aquatic environment and drinking water has raised the\nquestion of their impact on the environment and public health. Animal production is one of the\nmost expressive activities of Brazilian agribusiness. In order to ensure the productivity and\ncompetitiveness of the sector, the use of drugs for therapeutic and prophylactic purposes is a\ncommon practice. Due to the continuous release of antimicrobials into the environment, the aim\nof this study was to compare the frequency of detection of tetracyclines and sulfonamides in\nsurface water collected from rural areas in Lidice District of Rio Claro, in the State of Rio de Janeiro,\nBrazil. An investigative study was conducted with 24 river water samples analyzed by\nhigh-performance liquid chromatography coupled to tandem mass spectrometry and the aim of\nthis study was to determine residues of sulfonamides and tetracyclines based on the USEPA method\n1694. The results indicated the presence of sulfamethoxazole and oxytetracycline concentrations\nat the ngâË?â?¢LâË?â??1 level. The applied method showed overall good performance with recoveries\nabove 57%, method detection limits ââ?°Â¤ 7.17 ngâË?â?¢LâË?â??1, method quantification limits ââ?°Â¤ 23.90\nngâË?â?¢LâË?â??1 and good linearity....
A risk situation of organic pollutants accumulation in the sediments of the dams from Cascade\nââ?¬Å?Middle Iskarââ?¬Â (NW Bulgaria) is simulated in the present study. The aim is risk modelling of organic\npollution in lake sediments and on base of the investigated key chemical and enzymological\nparameters to risk assessment. A model process in lab scale with addition of whey as a source of\norganic pollutants was simulated. Two situations near to real conditions were studied: 1) at a decreased\nconcentration of organic pollutants (chemical oxygen demand was 0.265 gO2âË?â?¢kgâË?â??1) in the\ncase of discharge of sediments downstream of the river (control situation); 2) at an accumulation\nof organic pollutants (chemical oxygen demand was 1.463 gO2âË?â?¢kgâË?â??1) in the sediments (risk event).\nThe dynamics of chemical oxygen demand (COD), concentration of proteins and lactose as well as\nof the key enzymological indicators (phosphatase activity indexââ?¬â?PAI, anaerobic dehydrogenase\nactivity, protease and Ã?Ÿ-galactosidase activities) were investigated. The data from Risk Assessment\nshowed that there is a hazard from higher protein concentration at the end of the process in\ncomparison with the control situation. The risk about COD and lactose concentration during the\nrisk modelling was acceptable. The obtained results showed that the PAI can be used as an indicator\nfor early warning of the organic pollution with protein nature....
This study was conducted to investigate the\ncharacteristics of inflow and outflow wastewater of the\nBandargaz wastewater treatment plant on the basis of the\ndata collection of operation period and the samples taken\nduring the study. Also the effects of mid-term use of the\nwastewater for irrigation (from 2005 to 2013) on soil\nphysical and chemical characteristics were studied. For\nthis purpose, 4 samples were taken from the inflow and\noutflow wastewater and 25 quality parameters were measured.\nAlso, the four soil samples from a depth of 0ââ?¬â??30 cm\nof two rice field irrigated with wastewater in the beginning\nand middle of the planting season and two samples from\none adjacent rice field irrigated with fresh water were\ncollected and their chemical and physical characteristics\nwere determined. Average of electrical conductivity, total\ndissolved solids, sodium adsorption ratio, chemical oxygen\ndemand and 5 days biochemical oxygen demand in treated\nwastewater were 1.35 dS/m, 707 ppm, 0.93, 80 ppm and\n40 ppm, respectively. Results showed that although some\nrestrictions exist about chlorine and bicarbonate, the\ntreated wastewater is suitable for irrigation based on\nnational and international standards and criteria. In comparison\nwith fresh water, the mid-term use of wastewater\ncaused a little increase of soil salinity. However, it did not\nlead to increase of soil salinity beyond rice salinity\nthreshold. Also, there were no restrictions on soil in the\naspect of salinity and sodium hazard on the basis of many\nirrigated soil classifications. In comparison with fresh\nwater, the mid-term use of wastewater caused the increase\nof total N, absorbable P and absorbable K in soil due\nto high concentration of those elements in treated\nwastewater....
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