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JAE-HONG PARK IL-HYOUNG CHO SOON-WOONG CHANG 《Journal of environmental science and health. Part. B》2013,48(2):109-120
In this study, the photochemical degradation of livestock wastewater was carried out by the Fenton and Photo-Fenton processes. The effects of pH, reaction time, the molar ratio of Fe2 +/H2O2, and the Fe2 + dose were studied. The optimal conditions for the Fenton and Photo-Fenton processes were found to be at a pH of 4 and 5, an Fe2 + dose of 0.066 M and 0.01 M, a concentration of hydrogen peroxide of 0.2 M and 0.1 M, and a molar ratio (Fe2 +/H2O2) of 0.33 and 0.1, respectively. The optimal reaction times in the Fenton and Photo-Fenton processes were 60 min and 80 min, respectively. Under the optimal conditions of the Fenton and Photo-Fenton processes, the chemical oxygen demand (COD), color, and fecal coliform removal efficiencies were approximately 70–79, 70–85 and 96.0–99.4%, respectively. 相似文献
2.
Effects of a dynamic membrane formed with polyethylene glycol on the ultrafiltration of natural organic matter 总被引:1,自引:0,他引:1
Boksoon Kwon Noeon Park Jaeweon Cho 《Frontiers of Environmental Science & Engineering in China》2010,4(2):172-182
The formation of a dynamic membrane (DM) was investigated using polyethylene glycol (PEG) (molecular weight of 35000 g/mol,
concentration of 1 g/L). Two natural organic matters (NOM), Dongbok Lake NOM (DLNOM) and Suwannee River NOM (SRNOM) were used
in the ultrafiltration experiments along with PEG. To evaluate the effects of the DM with PEG on ultrafiltration, various
transport experiments were conducted, and the analyses of the NOM in the membrane feed and permeate were performed using high
performance size exclusion chromatography, and the effective pore size distribution (effective PSD) and effective molecular weight cut off (effective MWCO) were determined. The advantages of DM formed with PEG can be summarized as follows: (1) PEG interferes with NOM transmission
through the ultrafiltration membrane pores by increasing the retention coefficient of NOM in UF membranes, and (2) low removal
of NOM by the DM is affected by external factors, such as pressure increases during UF membrane filtration, which decreases
the effective PSD and effective MWCO of UF membranes. However, a disadvantage of the DM with PEG was severe flux decline; thus, one must be mindful of both
the positive and negative influences of the DM when optimizing the UF performance of the membrane. 相似文献
3.
The experiments for high head airlifting performance with vertical tube were examined for wastewater treatment. Comparing with the centrifugal pump and other pumps, the airlift pump has some problems and limited applications. However, an advantage of an airlift pump is in its geometrical simplicity, not having any moving parts, so it is suitable in lifting fluids including tiny pieces of metal or grit. In this study, for the purpose of high lifting head, an air jet nozzle was used. We have performed experimentally according to various characteristics of the airlift pump system such as the change of submerged depth, lifting head of liquid-air mixture (total head) and air flow rate. This work has verified through experiments that airlift pump shows lifting ability for 3 m (Sr = 0.3) in comparison with conventional height, 2 m (Sr = 0.4). Also, we suggested that the new airlift pump system with the air booster pump be used to improve the higher lifting head performance. 相似文献
4.
Comparison of the removal efficiency of endocrine disrupting compounds in pilot scale sewage treatment processes 总被引:2,自引:0,他引:2
The removal efficiency of endocrine disrupting compounds from effluents using pilot scale sewage treatment processes, including various treatment technologies, such as membrane bioreactors (MBR), nanofiltration (NF) and reverse osmosis (RO) for the purpose of water reuse, were estimated and compared. The calculated estrogenic activity, expressed in ng-EEQ/l, based on the concentration detected by GC/MS, and relative potencies for each target compound were compared to those measured using the E-screen assay. The removal efficiencies for nonylphenol, was within the range of 55-83% in effluents. High removal efficiencies of approximately >70% based on the detection limits were obtained for bisphenol A, E1, EE2 and genistein with each treatment processes, with the exception of E1 ( approximately 64%) using the MBR process. The measured EEQ values for the effluents from the MBR, NF and RO processes also indicated low estrogenic activities of 0.65, 0.23 and 0.05 ng-EEQ/l, respectively. These were markedly reduced values compared with the value of 1.2 ng-EEQ/l in influent. Consequently, the removals of EDCs in terms of the EEQ value from the biological and chemical determinations were sufficiently achieved by the treatment process applied in this study, especially in the cases of the NF and RO treatments. 相似文献
5.
Boksoon KWON Noeon PARK Jaeweon CHO 《Frontiers of Environmental Science & Engineering》2010,4(2):172-182
The formation of a dynamic membrane (DM) was investigated using polyethylene glycol (PEG) (molecular weight of 35000 g/mol, concentration of 1 g/L). Two natural organic matters (NOM), Dongbok Lake NOM (DLNOM) and Suwannee River NOM (SRNOM) were used in the ultrafiltration experiments along with PEG. To evaluate the effects of the DM with PEG on ultrafiltration, various transport experiments were conducted, and the analyses of the NOM in the membrane feed and permeate were performed using high performance size exclusion chromatography, and the effective pore size distribution (effective PSD) and effective molecular weight cut off (effective MWCO) were determined. The advantages of DM formed with PEG can be summarized as follows: (1) PEG interferes with NOM transmission through the ultrafiltration membrane pores by increasing the retention coefficient of NOM in UF membranes, and (2) low removal of NOM by the DM is affected by external factors, such as pressure increases during UF membrane filtration, which decreases the effective PSD and effective MWCO of UF membranes. However, a disadvantage of the DM with PEG was severe flux decline; thus, one must be mindful of both the positive and negative influences of the DM when optimizing the UF performance of the membrane. 相似文献
6.
Sarper SARP Sungyun LEE Noeon PARK Nguyen Thi HANH Jaeweon CHO 《Frontiers of Environmental Science & Engineering》2009,3(1):98-105
For effective wastewater reclamation and water recovery, the treatment of natural and effluent organic matters (NOM and EfOM), toxic anions, and micropollutants was considered in this work. Two different NOM (humic acid of the Suwannee River, and NOM of US and Youngsan River, Korea), and one EfOM from the Damyang wastewater treatment plant, Korea, were selected for investigating the removal efficiencies of tight nanofiltration (NF) and ultrafiltration (UF) membranes with different properties. Nitrate, bromate, and perchlorate were selected as target toxic anions due to their well known high toxicities. Tri-(2-chloroethyl)-phosphate (TCEP), oxybenzone, and caffeine, due to their different K ow and pK a values, were selected as target micropollutants. As expected, the NF membranes provided high removal efficiencies in terms of all the tested contaminants, and the UF membrane provided fairly high removal efficiencies for anions (except for nitrate) and the relatively hydrophobic micropollutant, oxybenzon. Through the wetlands, nitrate was successfully removed. Therefore, a fair process of combining membranes with an engineered wetland could be proposed for sustainable wastewater reclamation and optimum control of contaminats. 相似文献
7.
Various air pollution control (APC) techniques were employed in order to reduce emissions of air pollutants produced from
chemical plants, which have many different chemical production facilities. For an emission reduction of acid gases, this study
employed a method to improve solubility of pollutants by decreasing the operating temperature of the scrubbers, increasing
the surface area for effective contact of gas and liquid, and modifying processes in the acid scrubbers. To reduce emission
of both amines and acid gases, pollutant gas components were first separated, then condensation and/or acid scrubbing, depending
on the chemical and physical properties of pollutant components, were used. To reduce emission of solvents, condensation and
activated carbon adsorption were employed. To reduce emission of a mixture gases containing acid gases and solvents, the mixed
gases were passed into the first condenser, the acid scrubber, the second condenser, and the activated carbon adsorption tower
in sequence. As a strategy to reduce emission of pollutants at the source, this study also employed the simple pollution prevention
concept of modification of the previously operating APC control device. Finally, air emissions of pollutants produced from
the chemical plants were much more reduced by applying proper APC methods, depending upon the types (physical or chemical
properties) and the specific emission situations of pollutants. 相似文献
8.
Sarper Sarp Sungyun Lee Noeon Park Nguyen Thi Hanh Jaeweon Cho 《Frontiers of Environmental Science & Engineering in China》2009,3(1):98-105
For effective wastewater reclamation and water recovery, the treatment of natural and effluent organic matters (NOM and EfOM),
toxic anions, and micropollutants was considered in this work. Two different NOM (humic acid of the Suwannee River, and NOM
of US and Youngsan River, Korea), and one EfOM from the Damyang wastewater treatment plant, Korea, were selected for investigating
the removal efficiencies of tight nanofiltration (NF) and ultrafiltration (UF) membranes with different properties. Nitrate,
bromate, and perchlorate were selected as target toxic anions due to their well known high toxicities. Tri-(2-chloroethyl)-phosphate
(TCEP), oxybenzone, and caffeine, due to their different K
ow and pK
a values, were selected as target micropollutants. As expected, the NF membranes provided high removal efficiencies in terms
of all the tested contaminants, and the UF membrane provided fairly high removal efficiencies for anions (except for nitrate)
and the relatively hydrophobic micropollutant, oxybenzon. Through the wetlands, nitrate was successfully removed. Therefore,
a fair process of combining membranes with an engineered wetland could be proposed for sustainable wastewater reclamation
and optimum control of contaminats. 相似文献
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