Current Issue : October - December Volume : 2017 Issue Number : 4 Articles : 5 Articles
Municipal wastewater treatment plants (WWTPs) in Korea collect and treat not only\ndomestic wastewater, but also discharge from industrial complexes. However, some industrial\ndischarges contain a large amount of non-biodegradable organic matter, which cannot be treated\nproperly in a conventional biological WWTP. This study aimed to investigate the characteristics\nand biodegradability of the wastewater organic matter contained in the industrial discharges and to\nexamine the fate of the industrial discharges in a biologicalWWTP. In contrast to most previous studies\ntargeting a specific group of organic compounds or traditional water quality indices, such as biological\noxygen demand (BOD) and chemical oxygen demand (COD), this study was purposed to quantify\nand characterize the biodegradable and nonbiodegradable fractions of the wastewater organic matter.\nChemical oxygen demand (COD) fractionation tests and fluorescence spectroscopy revealed that the\nindustrial discharge from dyeing or pulp mill factories contained more non-biodegradable soluble\norganic matter than did the domestic wastewater. Statistical analysis on the WWTPs� monitoring\ndata indicated that the industrial discharge containing non-biodegradable soluble organic matter\nwas not treated effectively in a biological WWTP, but was escaping from the system. Thus, industrial\ndischarge that contained non-biodegradable soluble organic matter was a major factor in the decrease\nin biodegradability of the discharge, affecting the ultimate fate of wastewater organic matter in\na biological WWTP. Further application of COD fractionation and fluorescence spectroscopy to\nwastewaters, with various industrial discharges, will help scientists and engineers to better design\nand operate a biological WWTP, by understanding the fate of wastewater organic matter....
The sand content (%) in sediment varied from 24.08±6.2 to 82.31±0.63, silt from 14.88±0.44 to 39.97±4.88 and clay content from 2.18±0.2 to 29.46±3.37. The Total Organic Content (mg/g) (TOC) varied from 0.55±0.08 to 7.92±0.54. TOC was found negatively correlated with sand (P<0.05) and positively correlated with clay (P<0.05.). Among the heavy metals, copper (ppm) varied between 12.16±0.05 and 29.36±0.05, nickel (ppm) varied from 1.9±1.18 to 13.14±3.33, lead (ppm) from 7.88±0.48 to 30.15±0.52 and zinc (ppm) from 19.18±0.8 to 40.99±0.66. Zinc was found positively correlated with Cu (P<0.05). The reasons for the high concentration of the above heavy metals are attributed to anthropogenic activity and agriculture run off. However all the heavy metals (Cu, Ni, Pb and Zn) concentrations in the estuary sediments were found within the permissible limits (CPCB-Central Pollution Control Board)....
The performances of hydrological simulations for the Pearl River Basin in China were\nanalysed using the Coupled Land Surface and Hydrological Model System (CLHMS). Three datasets,\nincluding East Asia (EA), high-resolution gauge satellite-merged China Merged Precipitation Analysis\n(CMPA)-Daily, and the Asian Precipitation Highly-Resolved Observational Data Integration Towards\nEvaluation (APHRODITE) daily precipitation were used to drive the CLHMS model to simulate daily\nhydrological processes from 1998 to 2006. The results indicate that the precipitation data was the most\nimportant source of uncertainty in the hydrological simulation. The simulated streamflow driven by\nthe CMPA-Daily agreed well with observations, with a Pearson correlation coefficient (PMC) greater\nthan 0.70 and an index of agreement (IOA) similarity coefficient greater than 0.82 at Liuzhou, Shijiao,\nand Wuzhou Stations. Comparison of the Nash-Sutcliffe efficiency coefficient (NSE) shows that the\npeak flow simulation ability of CLHMS driven with the CMPA-Daily rainfall is relatively superior\nto that with the EA and APHRODITE datasets. The simulation results for the high-flow periods in\n1998 and 2005 indicate that the CLHMS is promising for its future application in the flood simulation\nand prediction....
Global temperature is predicted to increase in the end of the century and one\nof the primary consequences of this warming is the sea level rise. Considering\nthe vulnerabilities on coastal systems and water resources, it is important to\nevaluate the potential effects of this rising in coastal areas, since the saline intrusion\non rivers would be intensified, leading to problems related to water\nquality. In this context, the present work aimed to verify saline intrusion\nchanges along an important river, S�£o Francisco Canal, located in Rio de Janeiro\nState, Brazil. For this purpose, a hydrodynamic modeling was performed\nusing SisBaHiA, considering different sea levels and tide conditions. According\nto the results, it was verified the intensification on saline intrusion and\nhigher salinity values due to a sea level rise of 0.5 m. These results show that\nnew licenses for water withdrawals must be carefully analyzed as the fluvial\nflow plays an important role to contain the saltwater intrusion on the studied\nriver. Accordingly, it is recommended the evaluation of climate change effects\nin order to choose best strategies to reduce coastal vulnerability, and the use\nof this theme on environmental licensing and territorial planning, integrating\nwater planning with coastal management....
The successful application of hydrological models relies on careful calibration and\nuncertainty analysis. However, there are many different calibration/uncertainty analysis algorithms,\nand each could be run with different objective functions. In this paper, we highlight the fact\nthat each combination of optimization algorithm-objective functions may lead to a different set of\noptimum parameters, while having the same performance; this makes the interpretation of dominant\nhydrological processes in a watershed highly uncertain. We used three different optimization\nalgorithms (SUFI-2, GLUE, and PSO), and eight different objective functions (R2, bR2, NSE, MNS,\nRSR, SSQR, KGE, and PBIAS) in a SWAT model to calibrate the monthly discharges in two watersheds\nin Iran. The results show that all three algorithms, using the same objective function, produced\nacceptable calibration results; however, with significantly different parameter ranges. Similarly,\nan algorithm using different objective functions also produced acceptable calibration results, but with\ndifferent parameter ranges. The different calibrated parameter ranges consequently resulted in\nsignificantly different water resource estimates. Hence, the parameters and the outputs that they\nproduce in a calibrated model are ââ?¬Å?conditionedââ?¬Â on the choices of the optimization algorithm and\nobjective function. This adds another level of non-negligible uncertainty to watershed models, calling\nfor more attention and investigation in this area....
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