• Title/Summary/Keyword: Filtration experiment

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A Basic Study on the Anaerobic Wastewater Treatment using Nonwoven Fabric Filter Bioreactor (부직포 여과막 생물반응조의 혐기성 폐수처리에 관한 기초연구)

  • Kim, Taek-Su;Bae, Min-Su;Cho, Yun-Kyung;Cho, Kwang-Myeung
    • Journal of Korean Society on Water Environment
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    • v.21 no.5
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    • pp.464-469
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    • 2005
  • In the nonwoven fabric filter bioreactor (NFBR), both the construction and the operation costs could be saved because a high concentration of microorganism can be maintained in the reactor as in the membrane bioreactor. However, the NFBR process has been investigated only under aerobic and/or anoxic conditions, In this research, a basic anaerobic treatment experiment was performed at $35^{\circ}C$ by feeding an airtight NFBR with a concentrated synthetic organic wastewater. The organic loading rate (OLR) of the NFBR was increased stepwise from $0.25kg\;COD/m^3-day$ to $0.77kg\;COD/m^3-day$ by gradually decreasing the hydraulic retention time from 20 days to 13 days. The results of the research showed that the best COD removal efficiency achieved at the OLR of $0.67kg\;COD/m^3-day$ with a value of 99.3%. The methane content of the produced gas was highest with a value of 61.2% at the OLR of $0.33g\;COD/m^3-day$. The highest methane production rate was $0.89g\;COD/m^3-day$ at the same OLR. The operation was terminated at the OLR of $0.77kg\;COD/m^3-day$ because of the deterioration in COD removal efficiency, gas production rate, and the methane content of the gas. Further researches are recommended for the NFBR to be employed for anaerobic treatment of organic wastewaters.

Evaluation of Catchbasin for Increasing Interception Capability of Stormwater Runoff (강우유출수 차집능력 증대형 빗물받이의 성능 평가)

  • Han, Sangjong;Shin, Hyunjun;Hwang, Hwankook
    • Journal of Korean Society of Water and Wastewater
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    • v.31 no.6
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    • pp.567-575
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    • 2017
  • It is not cost effective to raise the density of catch basins in preparation for heavy rainfall in terms of construction and maintenance. Our researchers have developed the new catch basin for increasing interception capacity of runoff with internal filtration structure. To compare interception capacity of an existing catch basin with the invented catch basin, a hydraulic experiment device with 4% of road gradients and 0.2% of road gradients was constructed. For runoff conditions of 4.4 l/s, 6.7 l/s and 10.4 l/s, capability of runoff and separation capability of debris (sand and leaves) were evaluated. As the main experimental results, the effectiveness of the developed catch basin has been verified with an increase in interception rate of approximately 22% for the runoff of 6.7 l/s as heavy rainfall. However, the results of invented catch basin showed only 4.5% of settlement rate of debris regarding sand. Therefore, the authors proposed an improved tilted screen structure additionally. After reviewing the performance of improved catch basin, application of the invented catch basin is expected to drain runoff effectively when it is applied to the faulty road drainage section.

Purification and Characterization

  • Nam, Suk-Woo;Seo, Dong-Wan;Sung, Dae-Seok;Han, Jeung-Whan;Hong, Sung-Youl;Lee, Hyang-Woo
    • Archives of Pharmacal Research
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    • v.21 no.2
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    • pp.128-134
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    • 1998
  • Nitric oxide synthase, NOS (EC.1.14.13.39), was purified from bovine pancreas over 5,500-fold with a 7.6% yield using 30% ammonium sulfate precipitation, and $2^1$,$5^1$-ADP-agarose and calmodulin-agarose affinity chromatography. The purified bovine pancreatic NOS (bpNOS) showed a single band on SDS-PAGE corresponding to an apparent molecular mass of 160 kDa, whereas it was 320 kDa on non-denaturating gel-filtration. This indicated a homodimeric nature of the enzyme. The specific activity of the purified bpNOS was 31.67 nmol L-citrulline fored/mtn/mg protein and an apparent $K\textrm{m}$ for L-arginine was 15.72 $\mu\textrm{M}$, The enzyme activity was dependent on $Ca^{2+}$ and calmodulin, and to a lesser extent on NADPH, FAD and FMN. $H_4B$ was not required as a cofactor for the activity. In an inhibition experiment with L-arginine analogues, $N^G$-nitro-L-arginine (NNA) had the most potent inhibitory effect on bpNOS, and $N^{G}$, $N^{G1}$-dimethyl-L-arginine (symmetric; sDMA) did not have any inhibitory effect. Immunohistochemical analysis of the bovine pancreas using brain type NOS antibody (anti-bNOS antibody) revealed that acinar cells showed strong immunoreactivity against the antibody.

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Determination of Methoxyfenozide Residues in Water and Soil by Liquid Chromatography: Evaluation of its Environmental Fate Under Laboratory Conditions

  • Choi, Jeong-Heui;Mamun, M.I.R.;Shin, Eun-Ho;Kim, Hee-Kwon;El-Aty, A.M. Abd;Shim, Jae-Han
    • Toxicological Research
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    • v.24 no.3
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    • pp.207-212
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    • 2008
  • Pesticide residues play several key roles as environmental and food pollutants and it is crucial to develop a method for the rapid determination of pesticide residues in environments. In this study, a simple, effective, and sensitive method has been developed for the quantitative analysis of methoxyfenozide in water and soil when kept under laboratory conditions. The content of methoxyfenozide in water and soil was analyzed by first purifying the compound through liquid-liquid extraction and partitioning followed by florisil gel filtration. Upon the completion of the purification step the residual levels were monitored through high performance liquid chromatography(HPLC) using a UV absorbance detector. The average recoveries of methoxyfenozide from three replicates spiked at two different concentrations and were ranged from 83.5% to 110.3% and from 98.1% to 102.8% in water and soil, respectively. The limits of detection(LODs) and limits of quantitation(LOQs) were 0.004 vs. 0.012 ppm and 0.008 vs. 0.024 ppm, respectively. The method was successfully applied to evaluate the behavioral fate of a 21% wettable powder(WP) methoxyfenozide throughout the course of 14 days. A first-order model was found to accurately fit the dissipation of methoxyfenozide in water with and a $DT_{50}$ value of 3.03 days was calculated from the fit. This result indicates that methoxyfenozide dissipates rapidly and does not accumulate in water.

TiO2 Reuse and Recovery from the Photocatalytic Oxidation of Cu(II)-EDTA using TiO2/UV-A System (TiO2/UV-A 시스템을 이용한 Cu(II)-EDTA의 광촉매 산화반응에서 TiO2 재사용 및 회수)

  • Lee, Seung-Mok
    • Journal of Korean Society on Water Environment
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    • v.21 no.1
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    • pp.84-91
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    • 2005
  • $TiO_2-catalyst$ suspensions work efficiently in Photocatalytic oxidation (PCO) for wastewater treatment. Nevertheless, once photocatalysis is completed, separation of the catalyst from solution becomes the main problem. The PCO of Cu(II)-EDTA was studied to determine the reusability of the titanium dioxide catalyst. Aqueous solutions of $10^{-4}M$ Cu(II)-EDTA were treated using illuminated $TiO_2$ particles at pH 6 in a circulating reactor. $TiO_2$ was reused in PCO system for treatment of Cu(II)-EDTA comparing two procedures: reuse of water and $TiO_2$ and reuse of the entire suspension after PCO of Cu(II)-EDTA. The results are as follows; (i) Photocatalytic efficiency worsens with successive runs when catalyst and water are reused without separation and filtration, whereas, when $TiO_2$ is separated from water, the reused $TiO_2$ is not deactivated. (ii) The $TiO_2$ mean recovery (%) with reused $TiO_2$ was 86.4%(1.73g/L). Although the mean initial degradation rate of Cu(II)-EDTA and Cu(II) was lower than that using fresh $TiO_2$, there was no significant change in the rate during the course of the three-trial experiment. It is suggested that Cu(II)-EDTA could be effectively treated using an recycling procedure of PCO and catalyst recovery. (iii) However, without $TiO_2$ separation, the loss of efficiency of the PCO in the use of water and $TiO_2$ due to Cu(II), DOC remained from previous degradation and Cu(II)-EDTA added to the same suspension was observed after 2 trials, and resulted in the inhibition of the Cu(II)-EDTA, Cu(II) and DOC destruction.

A study on treatment of emulsified oil waste water in vessels by electrochemical treatment system (전기화학적 처리장치에 의한 유화된 선저폐수의 처리에 관한 연구)

  • Kwon K. S.;Jeong H. J.;Lee B. H.
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.6 no.3
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    • pp.45-53
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    • 2003
  • Discharging untreated bilge to the ocean is a cause of marine pollution. In general, bilge water contains free and/or emulsified forms of oil. Free form of oil can easily be separated by gravimetric flotation and/or proper filtration processes. However, those simple physicochemical processes could not separate emulsified oil without adding proper chemicals. Electrolytic flotation is one of promising technologies able to fulfill the effluent standard requirement, which is below 15 ppm of oil content. In this research, Electrochemical process consisting of electrochemical flotation basin was studied for the treatment of emulsified oil. In order to estimate, the effectiveness of oil separation equipment influent concentration of oil and HRT(Hydraulic retention time) were considered. Also, lab-scale electrochemical process was designed and operated in the condition of various HRT, current density, and electrode gap. Through the research, following results were obtained. From the experiment of bench scale electrochemical treatment process, it was demonstrated that the emulsified oil was treated effectively and the removal efficiency of emulsified oil from wastewater was increased with HRT and current density.

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Effects of Ethanol-extract of Allium wageki on the Renal Function of Fructose-induced Hypertensive Rats (쪽파 에탄올 추출물이 과당 유도 고혈압 백서의 신장 기능에 미치는 영향)

  • Kang Dae Gill;Lee An Sook;Lee Yun Mi;Sohn Eun Jin;Yeum Kee Bok;Lee Ho Sub
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.2
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    • pp.423-427
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    • 2003
  • The present study was aimed to investigate whether ethanol-extract of Allium wageki has an ameliorative effect on the renal function in high fructose-diet induced hypertensive rats .. The urine osmolality (Uosmol) was decreased in rats with high fructose-diet (60%) during the whole experiment period without change of the urine volume (UV). The urinary excretion of sodium (UNaV) and chloride (UCIV) were decrease significantly in rats with fructose-induced hypertensive rats, whereas urinary excretion of potassium (UKV) was Increased. The creatinine clearance (Ccr) and solute-free water reabsorption were also decreased by treatment of fructose-rich diet. Among these renal functional parameters, Ccr was partially restored by the administration of ethanol-extract of Allium wageki. The Uosmol was also partially restored by the administration ethanol-extract of Allium wageki at the end of the experimental period. Taken together, ethanol-extract of Allium wageki has the ameliorative effect on glomerular filtration rate in rats with high fructose-diet induced hypertension.

A study on induced polarization characteristics of sand and clay for alluvium investigation (충적층 조사를 위한 모래와 점토의 유도분극 특성 고찰)

  • Choi, Sang-Hyuk;Kim, Hyoung-Soo;Kim, Ji-Soo
    • 한국지구물리탐사학회:학술대회논문집
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    • 2008.10a
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    • pp.179-184
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    • 2008
  • Silt or clay alluvium fully saturated with water generally shows low resistivity. Sometimes it is believe that the low resistivity layer is considered as good aquifer but this makes problems in the development of groundwater. To overcome this problem, we adopted induced-polarization(IP) method with resistivity method. Laboratory experiments and resistivity/IP field surveys with non-polarization electrodes were conducted for the study. Laboratory experiments shows that the increase of clay contents in the sample mixed with sand and clay give low resistivity and high chargeability. We used this experiment results in the interpretation of resistivity/IP field data which were obtained in riverbank filtration. Finally, the layer which has low resistivity and chargeabilty would be regarded as a good aquifer for the development of groundwater intake.

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Effects of Saseuptang Water Extracts on the Renal Function in Rats (사습탕(瀉濕湯) 전탕액(煎湯液)이 백서(白鼠)의 신장기능(腎臟機能)에 미치는 영향(影響))

  • Min, Young-Kie;Yu, Yun-Cho;Lee, Ho-Sub;Ryu, Do-Gon
    • The Journal of Korean Medicine
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    • v.17 no.1 s.31
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    • pp.212-221
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    • 1996
  • The aim of this experiment was to elucidate the effects of Saseuptang water extract on the renal function plasma renin activity and plasma levels of atrial natriuretic peptide and aldosterone in rat The results were as follows; 1. Water balance decreased significantly after the administration of Saseuptang water extract, 0.4 and 0.8ml/kg. 2. Urine volume increased significantly after the administration of Saseuptang water extract, $0.4\;m{\ell}/kg$. 3. Urinary excretion of chloride increased significantly after the administration of Saseupthang water extract, $0.8\;m{\ell}/kg$. 4. Free water clearance increased significantly after the administration of Saseuptang water extract, $0.8\;m{\ell}/kg$. 5. Urinary excretion of creatinine increased significantly after the administration of Saseuptang water extract, $0.8\;m{\ell}/kg$. 6. Plasma levels of atrial natriuretic peptide (ANP) decreased significantly after administration of Saseupthang water extract, $0.8\;m{\ell}/kg$. These results suggest that the changes of urine volume after the administration of Saseuptang water extracts are related to the increments of glomerular filtration rate and free water clearance, and it is suggested that the changes of renal function by which Saseuotang may related to the renin-angiotensin and atrial natriuretic peptide system.

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Effects of Ethanol-Extract of Lotus Root on the Renal Function and Blood Pressure of Fructose-Induced Hypertensive Rats (연근의 에탄올 추출물이 과당으로 유도된 고혈압 흰쥐의 혈압과 신장 기능에 미치는 효과)

  • Park Sung-Hye;Ham Tae-Sick;Han Jong-Hyun
    • Journal of the East Asian Society of Dietary Life
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    • v.15 no.2
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    • pp.165-170
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    • 2005
  • The present study was aimed to investigate whether ethanol-extract of Nelumbo nucifera has an ameliorative effect on the renal function in high fructose-diet induced hypertensive rats. The urine osmolality (Uosmel) was decreased in rats with high fructose-diet ($60\%$) during the whole experiment period without change of the urine volume (UV). The urinary excretion of sodium and chloride were decrease significantly in rats with fructose induced hypertensive rats, wheras urinary excretion of potassium was increased. The creatinine clearance (CCr) and solute-free water reabsorption were also decreased by treatment of fructose rich diet. Among these renal functional parameters, CCr was partially restored by the administration of ethanol-extract of Nelumbo nucifera. The Uosmol was also partially restored by the administration ethanol-extract of Nelumbo nucifera at the end of the experimental period. Taken together, ethanol-extract of Nelumbo nucifera has the ameliorative effect on glomerular filtration rate in rats with high fructose-diet induced hypertension.

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